Previous Page Table of Contents Next Page

Insects in wheat-based systems
R.H. Miller, K.S. Pike

Hundreds of insects have been described on wheat worldwide. While most of these insects cause insignificant damage or occur only in isolated areas, others annually cause serious yield and forage reduction across international borders. Some of these insect pest problems are directly linked to the unique farming system employed in a particular area, while other pests are opportunistic or generalist herbivores that do not target wheat specifically as a host. Some wheat pests are adapted specifically to wheat and wheat relatives and to the set of environmental and physiographic conditions in which wheat is grown. As agriculture has expanded into areas not traditionally planted to wheat and as those agricultural practices themselves eliminate or hinder the natural regulating forces that would normally check their populations, many pest populations have erupted into severe outbreaks wreaking near-total destruction on the crops they infest. Stored products pests, most of which are protected within and infest the grain kernels, frequently have cosmopolitan distributions. These insect pests, if left unchecked, can devastate the quality and quantity of grain and fibre ultimately reaching the consumer.

Many of the major insect pests on wheat worldwide have their origins in the rainfed grasslands of West and Central Asia and along the Mediterranean rim, or at least are related to species that originated there. This region has long been considered home to the wild progenitors of wheat (Harlan, 1992). Since ancient times, wheat grown in these harsh but diverse agricultural zones has been distributed from the site of production to population centres full of consumers. As wheat production expanded from small plots hand-sown in the fertile soils of this region to larger, more labour-intensive farms, insect pests took advantage of the abundant food source that the development of agriculture afforded them. As wheat varieties were planted in regions that evolutionarily were unfamiliar to wheat production, insects undoubtedly took advantage of the reduced vigour and increased vulnerability of the plants. The transportation of wheat across national boundaries and oceans and into new and suitable growing environments introduced insect pest hitch-hikers as well. Numerous insect pests of wheat in almost all of the major wheat-producing areas of the world can be traced back to the centres of origin of their host plants. Other preadapted endemic plant pests infesting wild grasses or related crop plants were able to switch to the introduced wheat plants in their new setting. Quarantine restrictions through the ages seem only to have postponed, but not prevented, a substantial number of wheat pests from establishing themselves in new biogeographical zones. There, natural selection further refined them into races and biotypes capable of surmounting, over time, even the most resistant of genotypes.

Efforts to control insect pests of wheat and other low-input cereal crops generally take a back seat to the more pressing problems of abiotic production constraints, such as heat, drought, low soil fertility, salinity, day-length and so on. Even when these constraints are met, insect pests are frequently considered secondary to other biotic stresses, such as disease. It is not uncommon that the impact of insect pests is overlooked unless their effect is obvious through high crop loss or cosmetic damage. The symptoms of insect infestation may be masked by various abiotic and biotic factors, or the insect itself once discovered may be misidentified and incorrect treatments prescribed. In some cases, insect damage is mistaken for that caused by drought, heat, cold or disease. Entire loss of a wheat crop may be attributed to a single insect pest or to a closely related group of insects, although this is relatively rare. More often than not, wheat fields are quite free of insect pests. Those that occur are frequently found along field edges where plants are more likely to be subjected to water and other stresses and where the probability of encounter with a wandering insect is enhanced.

Insect pest management techniques in wheat, and in general agriculture, have evolved over the years according to resources available to wheat producers and as a response to the adverse impact some pest management strategies have upon the environment. Large-scale production practices were implemented on high-value crops following the Second World War. These were accompanied by rapid developments in synthetic chemistry, which led to the production of potent chemical pesticides such as DDT in 1939. Rapid knock-down, high target mortality, ease of application and low cost rapidly led to the adoption of DDT and other more potent compounds (Metcalf, 1982; Osteen and Szmedra, 1989). The use of synthetic pesticides soon became the predominant method of controlling crop pests and overshadowed, and in many cases eliminated, programmes of alternative methods of pest control. Coupled with increases in fertilizer production and mechanization, as well as the development of higher yielding varieties, wheat production in many of the developed countries of the world was revolutionized. Production of synthetic pesticides has continued since that time with new compounds and formulations being released annually. Use of insecticides on wheat in developing countries has generally lagged behind that of North America and Europe due to cost constraints associated with wheat as a low-input crop, as well as due to difficulties in obtaining and maintaining equipment and trained personnel. Because of the relatively low emphasis on insect pests in wheat-based systems, wheat varieties possessing resistance to insect pests have for the most part lagged behind the development of high-yielding, disease-resistant varieties, although there are some notable exceptions.

Total pesticide use in the United States has declined since 1982 from 270 million kg to 260 million kg in 1992 (NRC, 1996). Insecticide use on wheat in the United States is far below that used on fruit and vegetable crops and amounts to only about 3.5 percent of the total (Lin et al., 1995) although wheat ranks second in terms of total acreage. Part of the reason for this decline has been the realization that broad spectrum insecticides not only kill target pest species, but also kill natural enemies of those pests. Elimination of natural enemies disrupts the natural balance of the insect-plant system by allowing pests to multiply uncontrollably, sometimes resulting in new pest problems (Debach and Rose, 1977; Debach and Rosen, 1991; Gerson and Cohen, 1989; Huffaker et al., 1969, 1970; McMurtry et al., 1970).

Soon after pesticide use became widespread in the 1950s and 1960s, many growers found that 'old favourite' insecticides were no longer as effective as they once were. Higher application rates of those insecticides were required to obtain previous levels of suppression, and pesticides did not control some pests at all. Arthropod resistance to insecticides was first observed against DDT in Sweden in 1946 only seven years after its introduction (Gould, 1991). Since that time, numerous broad spectrum insecticides have been rendered useless and removed from the market due to insecticide resistance. In addition, concerns over health risks associated with applying insecticides with high mammalian toxicity or the ability to 'bioaccumulate' in the fatty tissues of non-target hosts have resulted in the passing of legislation in many countries restricting the type and distribution of insecticides. When coupled with the increasingly high costs of discovery and registration, these factors have led to an awareness that total reliance on chemical insecticides must be decreased, and eliminated if possible.

As the agricultural community became increasingly aware of the undesirable effects of total reliance on chemical insecticides, the idea that pest control could be founded on sound ecological principles was resurrected. Though many of the basic concepts were proposed as early as 1915 (Sanderson, 1915), the term 'integrated control' gained acceptance after Stern et al. (1959) used it to describe pest management strategies where limited chemical control was employed to enhance extant natural enemies or where natural enemies themselves were ineffective (Flint and van den Bosch, 1981). Inherent in the integrated control concept was the idea that control measures should not be implemented until pest populations reached levels where economic loss could be expected. The concept of an economic injury level (the pest density at which economic loss will occur) and an economic threshold (the pest density at which control measures must be implemented to avoid exceeding the economic injury level) was thus introduced.

Integrated control matured into integrated pest management (IPM) as pest managers and policy makers sought a more holistic approach to protecting crops while minimizing harm to the environment or to the health of the consumer and producer population. The basic concept underlying IPM is that natural and agricultural systems can be manipulated to increase the effectiveness of natural population controls without necessarily having to resort to chemical insecticides (NRC, 1996). Biological control, where natural enemies are introduced to control an introduced pest or augmented to control an endemic pest, remains the mainstay of IPM in the majority of agricultural systems. However, in many wheat-based systems, cultural control methodologies where agronomic practices, such as field sanitation, seeding rate and resistant varieties, are used to maintain pest populations below the economic threshold are of paramount importance as well.

In general, the development of IPM in wheat-based cropping systems, especially those in developed countries, has lagged behind IPM aimed at pests of high-value orchards, field crops and greenhouse cultures. IPM requires a more in-depth knowledge of the agro-ecosystem, not only of the pest species that may be found there, but also of the ecological links between the plant community, herbivores and natural enemies. Greater human resources in the form of IPM 'scouts' to monitor pest and natural enemy populations in the field and of IPM trainers who extend ecological knowledge about the cropping system to growers, farm workers and policy makers are often required for IPM to be successfully implemented. The overall cost of some IPM techniques, such as biological control and the use of pest-resistant varieties, may be relatively low and is often distributed among government agencies or grower cooperatives. Initial investment costs for research and technology transfer should be considered for the entire life of the natural enemy population or resistant variety, and not just for the year of its release. Often relatively small adjustments in farming strategies can be made that contribute to the control of pests.


Some wheat pests are of such paramount importance that they bear special mention or have the potential to spread to other similar agro-climatic zones where wheat is grown. Many of these pests, or groups of pests, typically undergo annual outbreaks in many countries and cause substantial crop losses. Most are not easily controlled with conventional pest management strategies, and due to the low amount of inputs on wheat in lesser developed countries, adequate resources are not available in a timely fashion (Srivastava et al., 1988). The description and control methods for these insects described hereafter may have wide application in countries where they currently are considered pests and in countries where they may yet become established.

Table 23.1 highlights wheat insect pests occurring on field-grown cereals. Information contained in the table indicates the most important range of infestation and common names used. While the list of insects contained in the table is extensive, it is not exhaustive.

Wheat IPM in the Nile River Valley of Egypt and Sudan

Wheat in Egypt and Sudan is grown in the tropical environments of the Nile River Valley and in large irrigated farms managed by farmer cooperatives. Several common aphid species attack wheat along the length of the Nile River Valley (Table 23.2), although the dominant aphid species change with increasing mean temperatures as one moves southward (Miller, 1994) (Figure 23.1). Rhopalosiphum padi (L.) causes the most serious yield losses in Middle and Upper Egypt, averaging 18 percent in unsprayed bread wheat and 16 percent in unsprayed durum wheat (Mossad et al., 1992; Tammam and Towfelis, 1992). High populations of R. padi literally desiccate wheat plants, causing extensive brown patches in infested wheat fields (Plate 58) (El Heneidy et al., 1991, 1992). Rhopalosiphum maidis (Fitch) is the dominant aphid species in the more temperate northwest coast, and though it vectors barley yellow dwarf virus (BYDV), it rarely causes notable direct damage to the plant. Sitobion avenae (F.) and Diuraphis noxia (Kurdjumov) rarely attain population levels high enough to warrant control efforts in Egypt. Schizaphis graminum (Rondani) is commonly observed on wheat throughout Egypt, but is rarely considered harmful there (Plate 59). However, S. graminum may attain sufficiently high densities in Sudan to cause the same type of direct feeding damage as R. padi does to the north in Egypt (Sharaf El Din, 1992). Direct damage to wheat in Sudan by S. graminum may result in up to 30 percent yield losses in unsprayed fields (Kannan, 1992). Rhopalosiphum padi, while present in Sudan, is generally observed earlier in the growing season than S. graminum in Sudan, and populations never attain high densities.

Aphid infestations in both Egypt and Sudan are commonly controlled by one or more applications of chemical insecticides. Field scouts monitor aphid populations and recommend spraying when densities exceed 30 percent infested plants in Egypt and 35 percent infested plants in Sudan (Miller, 1994). Pirimicarb and malathion are used extensively in Egypt, while Sudan has almost exclusively depended on thiometon for years. Each country evaluates new pesticides for release against aphids annually. Imidacloprid used as a seed treatment on wheat in Sudan has shown promise in controlling aphids (Sharaf El Din and Kannan, 1994) and was registered for use in the early 1990s.

Natural enemy surveys have shown that a number of hymenopteran parasitoids of aphids are present in or near wheat fields in Egypt (El Heneidy et al., 1992), as are several predators in both Egypt and Sudan (Table 23.2). However, hymenopteran parasitoids are uncommon in Sudan wheat fields where the main natural enemies are comprised of a few coccinellid, neuropteran and dipteran predators. Neither country, however, has sufficient natural enemies to retain aphid populations below economic thresholds. Pesticide use in Egypt frequently results in temporary reduction of hymenopteran parasitoids and predators (Plate 58), although even in unsprayed wheat fields natural enemy populations generally appear too late in the season and in such low numbers to exert much sup-pression of aphid populations. While Sudan's harsh climate, outside of the relatively cool winter growing season, may contribute to low parasitoid populations, it is also likely that heavy applications of broad spectrum insecticides on adjacent cotton fields planted concurrently with wheat have detrimentally reduced, if not eliminated, natural enemies from wheat fields.

TABLE 23.1
Some insects that infest wheat in the field


Scientific name




Haplothrips aculeatus F.

Western Europe

Haplothrips frogotti Hood


Haplothrips ganglbaueri Schmutz


Haplothrips tolerabilis Priesner


Haplothrips tritici Kurdjumov

Ear thrips; Europe, West Asia


Anaphothrips aculeatus Müller


Anaphothrips obscurus (Müller)

Holarctic; Peru

Aptinothrips stylifera Trybon


Frankliniella tenuicornis Uzel


Frankliniella tritici (Fitch)


Limothrips cerealium (Haliday)

Grain thrips; Western Europe, West Asia

Limothrips denticornis Haliday

Northern regions, Western Europe

Thrips angusticaps Uzel


Taeniothrips lefroyi Bagnall




Blissus leucopterus (Say)

Chinch bug; North & South America

Blissus diplopterus Distant

South Africa

Hudsona anceps (White)

Hudson's bug; New Zealand

Nysius ericae (Schiller)

False chinch bug; Europe, North America

Nysius huttoni White

Wheat bug; New Zealand

Nysius vinitor Bergr.

Fly bug; Australia


Anapus freyi Fieber

Russian Federation, West Asia

Adelphocoris rapidus (Say)

Cotton leaf bug; North America

Lygus pratensis L.

Tarnished plant bug; Europe, North Africa, North America

Lopus infuscatus Brulle

Central Europe

Miris dolobratus L.

Meadow plant bug; northern Europe; North America

Miris ferrugatus Fallén


Orthocephalus brevis Panzer

Russian Federation, West Asia

Stenotus binotatus (F.)

Timothy plant bug, slender crop mirid; Europe, North America, New Zealand

Trigonotylus ruficornis Geoffroy

Russian Federation, North America


Aelia acuminata L.

Pointed wheat shield bug; Europe, Asia, North Africa

Aelia cognata Fieber

North Africa

Aelia germari Küst

North Africa

Aelia rostrata Boheman

Pointed wheat shield bug; Middle East

Carpocoris fuscispinus Boheman

Iran, Central Asia

Dolycoris pennicillatus Horvath

Iran, Central Asia


Eurygaster austriaca Schrank

Wheat shield bug; North Africa, Asia

Eurygaster integriceps Puton

Sunn pest; Eastern Europe, Asia


Eurygaster maura L.

Sunn pest; West Asia, North Africa


Philaenus spumarius (L.)

Meadow froghopper; Europe, Asia, North America


Oliarius apicalis Uhler



Dicranotropis bipectinata Muir


Javesella pellucida F.

Europe, Egypt, Asia, Japan

Laodephax striatellus Fallén

Europe, Central Asia, Japan


Dictyophara patruelis Stål

China, Japan, Taiwan (Province of China)

Pyrilla perpusilla Walker

Indian sugar cane leafhopper; India, Sri Lanka


Scientific name



Baldulus maidis DeLog & Wolda

North & South America

Baldulus elimatus Ball.


Cicadulina storey; China

Vector maize streak & eastern wheat striate

Cicadulina mbila (Naude)

Vector maize streak & eastern wheat striate

Cicadulina parazeae Ghauri

Vector maize streak & eastern wheat striate

Empoasca nagpurensis Distant


Endra inimica (Say)

North America; vector wheat striate mosaic

Erythroneura limbata Mats.

India, Indonesia, China, Japan

Macrosteles laevis Ribaut

Europe, Asia; vector aster yellows

Macrosteles cristatus Ribaut

Finland, northern Europe

Macrosteles fascifrons Stål

North America; vector aster yellows

Nephotettix bipunctatus Uhler

Green rice leafhopper; India, southeast Asia, Taiwan (Province of China), Philippines

Psammotettix striatus L.

Europe, Central Asia, North America; vector winter wheat mosaic virus & wheat dwarf

Tettigella viridis L.

Green leafhopper; Europe, Asia

Tettigella guttigera Uhler


Typhlocyba maculifrons Motsch



Tricentrus bicolor Distant



Diuraphis frequens (Walker)

Minor pest; North America

Diuraphis noxia (Kurdjumov)

Russian wheat aphid; North & South America, Europe, Africa, Asia

Diuraphis tritici (Gillette)

Minor pest; Western wheat aphid; North America

Metopolophium dirhodum (Walker)

Rose-grain aphid; Europe, West Asia, North & South America

Metopolophium festucae cerealium Stroyan


Rhopalosiphum maidis (Fitch)

Corn leaf aphid; Europe, North & South America, West & Central Asia, Japan, Taiwan (Province of China); vectors BYDV

Rhopalosiphum padi (L.)

Bird cherry-oat aphid; Europe, West Asia, New Zealand; vectors BYDV

Rhopalosiphum rufiabdominalis (Sasaki)

Rice root aphid; North America

Schizaphis graminum (Rondani)

Greenbug; Europe, North & South America, Africa, Asia; vectors BYDV; biotypes recognized

Sipha flava (Forbes)

Yellow sugar cane aphid; North America

Sitobion avenae (F.)

English grain aphid; Africa, Europe, Asia, Japan, Indonesia, Taiwan (Province of China), North & South America; vectors BYDV

Sitobion graminis Takahashi

Minor pest; Africa, India, southeast Asia

Sitobion miscanthi (Takahashi)

Grain aphid; south-central Asia, East Asia, Australia, New Zealand

Tetraneura africana van der Goot

West Asia; on roots

Tetraneura nigriabdominalis (Sasaki)

Minor pest; Africa, South & southeast Asia, Australia, New Zealand, North America

Tetraneura ulmi (L.)

Europe, West Asia, North America; on roots


Porphyrophora tritici Bodenheimer

West & Central Asia; drought-stressed wheat

Porphyrophora polonica L.

West & Central Asia; drought-stressed wheat


Scientific name




Zabrus mono Men.

West & Central Asia

Zabrus tenebrioides Goeze

Wheat ground beetle; West & Central Asia

Harpalus tridens Morawiz



Calamobius filum Rossi


Dorcadion carinatum Pallas

Russian Federation, West Asia


Chaetocnema aridula Gyllenhal

Flea beetle; Europe, West Asia

Chaetocnema hortensis Geoffroy

Flea beetle; Europe, West Asia

Crepidodera ferruginea Scopoli

Wheat flea beetle; Europe, West Asia

Diabrotica undecimpunctata howardi Barber

Southern corn rootworm; North America

Marseulinia dilativentris Reiche

Cereal leaf beetle; West Asia

Oulema gallaeciana Heyden


Oulema lichenis Weisse

Europe, West Asia, Japan

Oulema melanopus (L.)

Cereal leaf beetle; Europe, North America, North Africa, West Asia

Phyllotreta vittula Redtenbacher

Barley flea beetle

Phyllotreta chotamica Duval



Epilachna similis Thunb.



Listronotus bonariensis (Kuschel)

Argentine stem weevil; South America New Zealand

Tanymecus dilatoicollis Gyllenhal

Central Europe

Tanymecus indicus (Faust)


Pachytychius latipes Desbrochers des Loges

West Asia


Agriotes lineatus (L.)

Striped elaterid beetle (wireworm); West Asia, Europe

Agriotes spp.

Wireworms; Europe

Melanotus spp.

Wireworms; North America

Limonia spp.

Wireworms; North America


Helophorus nubilus F.

Central Europe, West Asia, China


Amphimallon majalis Razum

Europe, North America

Amphimallon solstitiale L.


Amphimallon ruficornis L.


Amphimallon caucasicum Gyllenhal


Anisoplia austriaca Herbst

Europe, West Asia

Anisoplia agricola Poda

West Asia

Anisoplia segetum Herbst

Central & southern Europe

Anisoplia leucaspis LaPorte

Eastern Europe, West & Central Asia

Costelytra zealandica (White)

Grass grub; New Zealand

Melolontha melolontha L.

Europe, West Asia

Phyllophaga crinita Burmeister

North America

Phyllopertha horticola L.

Garden chafer; Europe, West Asia

Phyllopertha campestris Latreille

Mediterranean rim

Phyllopertha nazarena Mars.

Winter wheat scarab; West Asia

Polyphylla irrorata Gebler

Russian Federation, West Asia

Popilla japonica Newman

East Asia, North America

Pseudoapterogyna numidicus Lucas

North Africa

Rhizotrougus caucasicus Gyllenhal

West Asia



Coleophora ciconiella Herrich-Schäffer

West & Central Europe; West Asia


Sitotroga cerealella (Olivier)

Angoumous grain moth, cosmopolitan, larvae also infest stored grain


Hepialus humuli (L.)

Ghost moth; Europe

Hepialus lupulina L.

Garden swift moth; Europe, West Asia


Scientific name



Agrotis flammatra Denis & Schiffermüller

West Asia

Agrotis ipsilon Hufnagel

Dark sword grass moth; Europe, Africa India, Australia, New Zealand, North & South America

Agrotis ipsilon aneituma (Walker)

Greasy cutworm; New Zealand

Agrotis orthogonia Morrison

Pale western cutworm; North America

Agrotis pronuba (L.)

West Asia

Agrotis segetum Schiffermüller

Turnip moth; Europe, Africa, Asia

Amathes xanthographa Schiffermüller

Europe; North Africa

Apamea sordens Hufnagel

Rustic shoulder knot moth; Europe, Japan, North America

Euxoa auxiliaris (Grote)

Army cutworm; North America

Hadena basilinea F.

Europe, West Asia, Japan, North America

Hadena secalis L.

Common rustic moth; Europe, North Africa, West Asia

Hadena sordida Borkh.

Russian Federation, West Asia

Meliana albilinea Hübner


Ochropleura fennica Tausch.

Northern Europe, West Asia, North Americ

Ochropleura flammatra Schiffermüller


Oria musculosa Hübner

Wheat stem borer; West Asia, North Africa

Peridroma saucia Hübner

Europe, North Africa, North & South America

Persectania aversa (Walker)

Southern armyworm; New Zealand

Pseudaletia adultera Schaus


Pseudaletia convecta (Walker)


Pseudaletia separata (Walker)

Cosmopolitan armyworm; New Zealand, India

Pseudaletia unipuncta (Haworth)

Armyworm; Europe, India, Japan, Australia, North & South America

Scotia crassa Hübner

Mediterranean rim

Scotia exclamationis L.

Heart and dart moth; North Africa

Sesamia cretica Lederer


Sesamia inferens (Walker)

India, China, Japan

Sesamia nonagrioides Lefebre

Southern pink borer; Europe, Africa, Malaysia

Sesamia uniformis Dudgeon


Spodoptera exempta (Walker)



Ochsenheimeria taurella Schiffermüller

Russian Federation, West Asia


Chilo partellus (Swinhoe)


Momophila noctuella Schiffermüller

North America


Syringopais temperatella Lederer

Cereal leaf miner; West Asia


Cnephasia longana (Haworth)

North America, Europe

Cnephasia pumicana (Zeller)

Cereal tortrix moth; Europe, West Asia

Cnephasia pasiuana Hübner

Europe, West Asia



Agromyza nigrella Rondani

Europe; wheat

Agromyza intermittens Becker

Europe; wheat & barley

Agromyza luteitarsis Rondani

Europe; wheat & barley

Cerodontha australis Malloch

Wheat sheath miner; New Zealand, Australia


Atherigona falcata Thorns.


Atherigona naquii Steyskal


Atherigona nudeseta Malloch


Atherigona indica Malloch


Delia arambourgi (Seguy)

Ethiopia, Libya

Delia platura (Meigen)

Barley shoot fly; Morocco, Libya, North Africa, Zimbabwe


Scientific name


Hylemyia securis Tiensuu

Central & Eastern Europe, West Asia

Phorbia arambourgi Seguy

Grey fly, black fly; North Africa

Phorbia coarctata (Fallen)

Wheat bulb fly; Europe, West Asia


Bibio marci L.

St. Mark's fly; Europe, West Asia

Bibio johannis L.


Bibio ferruginatus L.



Contarinia tritici (Kirby)

Lemon wheat blossom midge; Europe

Haplodiplosis equestris Wagner

Saddle gall midge; Europe, West Asia

Mayetiola destructor (Say)

Hessian fly; Mediterranean rim, West Asia, Europe, New Zealand, North America; biotypes recognized

Mayetiola hordei Keiffer

Barley stem gall midge; North Africa

Sitodiplosis mosellana (Gehin)

Orange wheat blossom midge; Europe, West Asia, North America


Chlorops pumilionis Bjerk.

Gout fly; Europe, West Asia

Chlorops mugivora Nishijma & Kanmiya


Camarota curvinervis Latreille

France, Italy

Meromyza saltatrix L.

Europe, West Asia, North America

Meromyza variegata Meigen

Russian Federation, West Asia

Meromyza americana Fitch

Wheat stem maggot; North America

Oscinella frit (L.)

Frit fly; Europe, West Asia, North America

Oscinella pusilla Meigen

Mainly on barley; Europe, West Asia

Oscinis soror Macquart

North America

Oscinis corbonaria Loew

North America

Elachiptera cornuta Fallén

Europe, West Asia; on wheat attacked by frit fly


Hydrellia griseola Fallén

Rice leaf miner; Europe, West Asia


Opomyza florum F.

Grass fly; Europe, West Asia

Opomyza germinationis L.

Germany, France

Geomyza combinata L.



Nephrotoma maculata Meigen


Nephrotoma flavescens L.


Tipula paludosa Meigen

Cranefly; Europe

Tipula oleracea L.

Cranefly; Europe

Tipula italica Lack

Cranefly; Europe

Tipula simplex Doane

Cranefly; North America



Cephus cinctus Norton

Wheat stem sawfly; Europe, North America

Cephus libanensis Andra

Lebanese stem sawfly; West Asia

Cephus pygmaeus (L.)

European wheat stem sawfly; Europe, North Africa, West Asia

Trachelus judaicus Konow

West Asia

Trachelus tabidus F.

Black stem sawfly; West Asia, North Africa, North America


Harmolita tritici (Fitch)

Wheat joint worm; Russian Federation, West Asia, North America

Harmolita grandis (Riley)

Wheat straw worm; North America, Eastern Europe, West Asia

Harmolita vaginicola (Doane)

Sheath gall joint worm; North America

Harmolita noxiale Portch.

Russian Federation


Dolerus haematodes Schrank


Dolerus migratus Müller


Dolerus ephippiatus Smith

Dem. People's Rep. Korea, Rep. Korea

Pachynematus clitellatus Lepeletier


Pachynematus extensicornis Norton

Wheat sawfly; North America

Source: CSIRO, 1970; Bonnemaison, 1980; Paulian and Popov, 1980; Blackman and Eastop, 1984; Burnett, 1984; Borror et al., 1989; Miller, 1991; Remaudière and Remaudière, 1997.

Since the potential for biological control in Egypt and Sudan appears low due to high pesticide use on adjacent crops and the phenology of aphid parasitoids, efforts have been made to identify wheat germplasm possessing resistance to R. padi for use in Egypt and to S. graminum for use in Sudan. In 1984, an aphid-screening laboratory was established in Giza, Egypt, to identify wheat lines with aphid resistance. Since its inception, nearly 5 000 lines per year, originating from Egyptian and Sudanese national programmes, International Center for Agricultural Research in Dry Areas (ICARDA), International Maize and Wheat Improvement Center (CIMMYT) and various germplasm collections outside of the region, have been screened against field collected R. padi and S. graminum (El Einen et al., 1989; Miller et al., 1992).

TABLE 23.2
Cereal aphids reported infesting wheat in Egypt and Sudan and their natural enemies, 1988-1992




Schizaphis graminum (Rondani)

S. graminum

Rhopalosiphum padi (L.)

R. maidis

R. maidis (Fitch)

R. pad;

Sitobion avenae (F.)

Diuraphis noxia (Kurdjumov)

Natural enemies

Coccinella spp.

Coccinella spp.

Chrysopa spp.

Cydonia spp.


Chrysopa spp.

Diaeretiella rapae (McIntosh)

Aphidius spp.

Source: After Miller, 1994.

Resistance to Egyptian S. graminum has been found in crosses between the Egyptian commercial varieties Giza 157, Sakha 61 and Sakha 69 and Bushland-Amigo (TAM 101, TAM 105) lines containing the R2 translocation from rye (Youssef et al., 1992a). Resistance to R. padi was observed in crosses made by the Egyptian national programme (Youssef et al., 1992b) and also in several Aegilops accessions (Youssef et al., 1992a).

Data accumulated over many years in the Nile River Valley suggest that a sufficient number of IPM tools and the experience to use them exist for successful IPM (Miller, 1994). It appears that using aphid-resistant varieties in combination with enhancing, or re-establishing as in the case of Sudan, natural enemy populations should be the foundation of IPM in Egypt and Sudan. Grain yield would not be sacrificed by implementing resistant varieties, as studies have shown that adequate aphid resistance is available in varieties that exceed or match currently used commercial varieties. Even moderate aphid resistance would likely be useful in reducing the number of sprays currently used on wheat in both countries. It is unlikely that resistant varieties or natural enemies alone will maintain pest populations at acceptable levels, and back-up sprays may be appropriate during outbreaks. Scouting and application procedures, while used in both countries, may not always be effective. Too frequently, a large region is sprayed based on population censuses from a relatively small portion of the region (Miller, 1994). Follow-up surveys to assess the effectiveness of the spray programme are frequently not conducted. Logistical problems may also cause delays in treating infested areas. Equipment, chemicals or personnel may not be available when needed. However, lowering the economic threshold to initiate earlier spraying may lead to an overuse of pesticides with the associated risks of environmental contamination and resistance build-up.

Wheat aphids of South America and their control

Wheat in South America is grown principally in the Southern Cone region comprised of central Argentina (Pampas region), southern Brazil, central Chile and parts of Paraguay and Uruguay. Cereal aphids, which are not native to the region, first caused problems in wheat in the late 1960s and 1970s (Lara and Zuniga, 1969). Injurious aphid populations during this period were linked mainly to an absence in natural enemy parasitoids (van den Bosch, 1976) and to diminished effectiveness in endemic predators and pathogens as a result of extensive and frequent use of pesticides (Zuniga, 1990). These conditions, together with encouragement of several scientists (Hille Ris Lambers, 1975; van den Bosch, 1976), led to the start of a large and timely biological control programme in Brazil, Chile and Argentina. Today, South American wheats are relatively free of economically injurious aphid populations. The potential aphid pests (rose-grass aphid, Metopolophium dirhodum (Walker); English grain aphid, S. avenae; greenbug, S. graminum; bird cherry-oat aphid, R. padi; and Russian wheat aphid, D. noxia, which is not found in Brazil, Paraguay or Uruguay) are held in check or at below economic injury levels under most circumstances - greenbug in Brazil's state of Parana is problematic at times on wheat and sorghum (Reed and Pike, 1990) - by a combination of factors, but especially by natural enemies and native predators (Zuniga, 1990; Starý et al-., 1993).

In total, more than a dozen parasitoid natural agents were introduced and established in the Southern Cone region of South America (Starý, 1995). Most of these were imported more than a decade ago from the Mediterranean-European area. Their success, continuance, and action levels in wheat is favoured by the matrix of assorted crops and habitats commonly associated with wheat production in the Southern Cone region. Such crops and habitats serve as a natural refuge and/or as a source of alternate aphid hosts for the bioagents (Starý et al., 1993).

Distribution of aphids (size of aphid indicates relative abundance) in wheat-growing areas of the Nile River Valley in Egypt and Sudan

Source: Miller, 1994.

Russian wheat aphid IPM

In the 1980s, the Russian wheat aphid (RWA), D. noxia, became established as a major aphid pest of wheat in Europe, Africa, Asia and North and South America (Hughes and Maywald, 1990) where it has caused crop losses of up to 80 percent in heavily infested areas (Plate 60). Most likely originating on wild grasses in mountainous areas of West and Central Asia, it entered Mexico in 1980 (Gilchrist et al., 1984) and was first detected in the United States in 1986 (Araya et al., 1990). It currently occurs throughout the low-rainfall wheat-producing areas of the western states and in parts of the Southern Cone region of South America. In Africa, its most severe infestations have occurred on rainfed wheat and barley in the highlands of Ethiopia (Haile and Megenasa, 1987) and in South Africa (Walters et al., 1980; Hewitt and Kriel, 1984; Aalbersberg et al., 1987). Russian wheat aphid has been collected on wheat and barley throughout the Mediterranean region where it attains pest status during years of prolonged drought, but in years of normal rainfall it usually remains an innocuous resident of wild and domestic grasses (Miller et al., 1993).

For many years, symptoms of D. noxia infestation were often misdiagnosed as a viral disease called Free State Streak Mosaic Virus (Zillinsky, 1983; Gilchrist et al., 1984). Russian wheat aphid symptoms on plants include longitudinal chlorotic streaks on the stem and leaves, severe rolling of the leaves and curling of the rachis (Plate 61, Plate 62). Feeding within the tightly rolled leaves, RWA is protected from the elements and from many natural enemies. Damage to plants appears more serious during drought or in semi-drought conditions. Distribution patterns of RWA in Syria suggest that aphids are caught up in prevailing westerly winds and deposited annually in Syria and Jordan in isolated spots in cereal fields well inland from the Mediterranean Sea (Miller and Ghannoum, 1994). Reservoir populations of RWA may be found in irrigated fields as well, located most commonly on the periphery of flood-irrigated or centre-pivot sprinkler-irrigated fields where ephemeral drought stress is likely to occur (Miller et al., 1993). Russian wheat aphid does not normally achieve pest status in areas of high rainfall (more than 350 mm) or where there is high relative humidity.

The cryptic behaviour of RWA makes it difficult to control using conventional insecticides. Some success has been achieved using insecticides that have systemic action, such as imidacloprid, or that are passed through interstitial spaces, such as pirimicarb. Other pesticides have been examined for use against RWA as well (Bayoun et al., 1995; Hill et al., 1996), although the high cost of these products prohibits their use on a large scale in rainfed areas of most developing countries.

Resistant wheat lines have been examined, and resistant varieties released for use against RWA (Baker et al., 1994; Quisenberry and Schotzko, 1994; Martin and Harvey, 1995; Rafi et al., 1996). When combined with biological and cultural control, these varieties offer an acceptable alternative to chemical insecticides for RWA control.

Numerous natural enemies have been recorded for RWA, with some of the earliest being recorded from South Africa (Aalbersberg et al., 1988) and Ethiopia (Haile and Megenasa, 1987). In the United States, research on the biological control of RWA resulted from an integrated federal- and state-funded management strategy for RWA entitled the National Russian Wheat Aphid Integrated Pest Management Program (NRWA-IPM) (Meyerdirk, 1989). Extensive collecting efforts, concentrating mainly on the suspected site of origin of RWA in West and Central Asia, brought many hymenopteran natural enemies of RWA to the United States where they were ultimately released in areas newly infested by RWA (Gilstrap et al., 1992; Hopper et al., 1992; Tanigoshi et al., 1995; Hopper et al., 1998).

Today, RWA appears to be under natural control in many regions where it was introduced in North America. This is probably due to the combined actions of introduced biological control agents and switching onto RWA by endemic natural enemies (Pike et al., 1999), the use of RWA-resistant varieties and other cultural controls, such as avoiding planting during RWA flight periods (Hammon et al., 1996). The massive biological control exploration and introduction programme in North America has been dismantled, with only a few workers following up on natural enemy releases made in previous years.

Russian wheat aphid remains a serious threat to rainfed wheat in many developing countries beset by sporadic drought. Resistant varieties adapted from breeding programmes in North America, South Africa, and by international agricultural research centres (IARCs) and national programmes themselves, are being developed for use in these countries. The effect of biological control is probably less apparent in many developing countries compared with North and South America since RWA, along with its natural enemies, is endemic to many of them (Rechmany et al., 1993).

Sunn pest IPM in West Asia

The name sunn pest or suni bug (Family: Scutelleridae) generally refers to the well-known and widespread species Eurygaster integriceps Puton (Plate 63), but is also commonly applied to other members of the genus Eurygaster that infest wheat and barley, including E. austriaca Schrank and E. maura L. (Talhouk, 1969; Paulian and Popov, 1980). Other hemi-pteran wheat and barley pests that resemble sunn pests in appearance and behaviour are the pointed wheat shield bugs in the genus Aelia (Pentatomidae). The most important of these are A. acuminata L., A. rostrata Boheman, A. cognata Fieb. and A. germani Küst. Other important pentatomid cereal bugs are Dolycoris pennicillatus Horvath and Carpocoris fuscispinus Boheman. The wheat bug, Nysius huttoni White (Lygaeidae), has attacked wheat in New Zealand since the mid 1930s and is often associated with two other hemipterans of indeterminate pest status, the Hudson's bug, Hudsona anceps (White) (Lygaeidae), and the slender crop mirid, Stenotus binotatus (F.) (Miridae) (Burnett, 1984).

Sunn pests and pointed wheat shield bugs are widespread throughout the rainfed grain-producing regions of southern and eastern Europe, northern Africa, and southwestern and south-central Asia. The most severe out-breaks occur on the Anatolian Plateau of Asia Minor, in the northern Black Sea and Caspian Sea drainages and in the highlands of northern Syria, Iraq and Iran (Paulian and Popov, 1980; Mamluk et al., 1992; Rassipour et al., 1996). Pest species of sunn pest do not occur in North America although habitat conditions appear optimal for them there.

Wheat is the most common host, although barley, rye, oats, sorghum and maize may also be attacked. Wheat plants are injured when sunn pests extract fluids from stems, leaves or developing grains thereby reducing plant vigour. When feeding on kernels, the sunn pest ingests the milky endosperm, which may result in a 15 to 60 percent reduction in kernel weight. Both nymphs and adults inject a proteolytic enzyme while feeding that aids in dissolving plant proteins. Leaf or stem tissues surrounding the feeding site die (Plate 64). The enzymes remain in a dehydrated, inactive state within the kernels after the insect ceases to feed. When water is added to flour milled from infected grain, these enzymes are reactivated and destroy the dough's gluten. Such dough lacks adequate gluten strength and cannot be used to make bread (Cardona et al., 1983; Burnett, 1984).

Life histories are similar for the sunn pest, pointed wheat shield bugs and other cereal bugs. Eurygaster species are generally univoltine, while Aelia species are multivoltine. The sunn pest overwinters as a sexually immature adult under rocks and fallen leaves and in bark crevices on hills and mountains surrounding cereal-growing areas. Fully mature adults migrate in the spring to cereal fields at lower elevations where they begin to feed and later mate and oviposit on weeds and wheat. The eggs normally hatch within ten days at which time the newly emerged nymphs (Plate 65) begin to feed. When sufficient body fat is accumulated, the sunn pests migrate to over-wintering sites. During a typical winter, about 25 percent of the sunn pest population dies, mostly due to inadequate internal fat body food reserves (Popov, 1979, 1985). Surviving sunn pests begin to move to cereal fields when ambient temperatures reach about 12°C.

Without exception, countries infested by sunn pests rely on chemical sprays for control. Sprays are most commonly aerially applied ultra low volume (ulv) applications of synthetic pyrethroids. In most Middle Eastern countries, decisions on when to spray are based on winter counts of overwintering sunn pests and the extent of body fat accumulation. Sprays typically are applied to wheat fields when economic thresholds of 6 to 12 nymphs/m2 or 2 to 3 adults/m2 are observed. Sprays are not recommended when egg parasites are observed in the field (Simsek et al., 1996).

Numerous invertebrate, vertebrate and pathogenic natural enemies of the sunn pest have been described (Table 23.3). However, large-scale biological control of sunn pests has been practised only in Iran, where high natural populations of sunn pest have allowed the collection of adults from hibernation sites for use in mass rearing parasitoids (Skaf, 1996). Iran and other countries experiencing severe outbreaks of sunn pest in large measure abandoned biological control in favour of chemical control once insecticides and delivery equipment became available in the late 1950s (Figure 23.2). Governments of sunn pest-affected countries bear most or all of the costs of the insecticide-based control programmes. Such government control has hindered the development and practice of IPM by reducing the interaction between researchers, extension agents, farmers and consumers. Once chemical control programmes have been established in affected countries, input from researchers on alternative control methods have generally ceased. The regional nature of sunn pest infestations, where overwintering sites may be across international borders from cereal fields, also hinders sunn pest IPM.

Most of the information available on sunn pest today was generated in the 1950s and 1960s by the Food and Agriculture Organization of the United Nations Regional Collaborative Programme on Sunn Pest Control. Later, international conferences on sunn pest control sought to foster international collaboration on implementing IPM, to establish networks for regional sunn pest control activities and to facilitate research and information transfer among affected countries. These activities have been only partially successful. Sunn pest continues to be one of the most damaging cereal pests worldwide (Miller and Morse, 1996).

Biological control tactics include mass releasing egg parasites and enhancing parasite habitat by growing shelter belts of trees around wheat fields. Other cultural control methods include planting early-maturing wheat and barley varieties, restricting wheat and barley cultivation in high pest density areas and disrupting the coincidence of ripe grain and young sunn pest adults by early harvesting (Javahery, 1996).

TABLE 23.3
Some natural enemies attacking Eurygaster species



Family: Scelionidae

Family: Nabidae

Telenomus chloropus Thoms.

Nabis pseudoferus Remane

Trissolcus grandis Thoms.

Nabis feroides Remane

Trissolcus pseudoturesis Rjakovsky

Nabis ferus L.

Trissolcus simoni Mayr

Nabis rugosus L.

Trissolcus semistriatus Nees.

Trissolcus rufiventris Mayr


Family: Chrysopidae

Family: Encyrtidae

Chrysopa spp.

Ooenocyrtus telenomicida Vassiliev



Family: Coccinellidae

Family: Phasiidae

Coccinella punctatum L.

Allophora subcoleioptrata L.



Phasianus cholchicus L.

Beauveria bassiana Vuill.

Perdix perdix L.

Bacillus thuringiensis Berliner

Coturnix coturnix L.

Fusarium spp.

Coracias garrulus L.

Rickettsiella urygasteris Lukyanchidov

Lanius spp.

Spicaria farinosa Hart.

Source: Erdos, 1960; Safavi, 1968; Kozlov and Kononova, 1983; Rosca et al., 1996; Voegelé, 1996.

Hessian fly

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), has long been a wheat pest in regions adjacent to the Mediterranean Sea in northern Africa, southern Europe and western Asia (Plate 66). As wheat products from straw have been transported, the Hessian fly has been distributed through-out Europe, into North and South America and into Australia and New Zealand. Especially severe economic losses have been observed in northern Africa.

Adult Hessian flies are small, grey flies that resemble mosquitoes. The egg is approximately 0.5 mm in length, slender, glossy and pale red in colour, becoming a deeper red near hatching (Burnett, 1984). First instars are the same size and colour as eggs. After three days, first instars turn completely white and reach a length of about 1.4 mm before moulting. Second-instar larvae initially have well-defined segmentation, but become completely smooth and cylindrical after three to four days. Hessian fly adults can be distinguished from the similar barley stem gall midge, M. hordei Keiffer, by comparing male genitalia and the abdominal segments of females. The third instar and pupa of both flies are enclosed in a 'flax seed' puparium formed from the hardened cuticle of the second instar (Plate 67, Plate 68). The puparium of the Hessian fly readily comes loose from plant tissue in contrast to that of the barley stem gall midge which adheres tightly to plant tissue (Gagné et al., 1991; Lhaloui, 1995).

Major insecticides used and area sprayed against sunn pest in Iran

Source: After Javahery, 1996; Rassipour et al., 1996.

Susceptible wheat plants are stunted and dark green in colour. Symptoms of infestation may be mistaken for those caused by drought stress. However, Hessian fly infestation may be differentiated by the presence of white larvae or dark coloured flax seed puparia at the base of the stems and under leaf sheaths.

The Hessian fly normally undergoes two full generations and a partial third generation in northern Africa. The third generation is completed if weather conditions are favourable. The first generation emerges about two weeks after the first significant rain, which normally corresponds to seeding time in late autumn. It requires about two months to complete its life cycle, as does the second generation. Some third instars of the second generation may enter diapause. Adult flies live for only a few days. Mating may occur within 30 to 60 minutes after emergence from the puparium. Oviposition occurs a few hours later and may extend over two days. Eggs are laid in the grooves between the longitudinal veins of leaves. Newly emerged larvae crawl down the leaves to the base of the stem where they begin to feed. Diapausing third instars may survive more than one year.

Planting wheat after the peak of adult emergence allows the crop to escape heavy infestation. Adequate fertilization enhances tillering and plant vigour and increases plant tolerance to the pest. Chemical control is effective (Bennany and Riany, 1978; Lhaloui et al., 1992), but is not normally economically feasible. Sources of host plant resistance have been identified in cultivated (Hatchett and Gallun, 1970; Cox and Hatchett, 1986) and wild wheats (Hatchett and Gill, 1983; Cox et al., 1990; Cox and Hatchett, 1994) and are widely used in breeding programmes to develop resistant varieties in developed and developing countries.

Migratory locusts

The two most important species of migratory locusts worldwide are Locusta migratoria migratoides (Reiche & Fairmaire), the African migratory locust, and Schistocerca gregaria (Forskal), the desert locust. Both are in the family Acrididae in the order Orthoptera. Of the two, S. gregaria is the more serious pest and has received extensive attention in terms of research and management.

Individuals of both species are large, brownish grasshoppers ranging from 5 to 8 cm in length (Popov, 1989). Both species are polymorphic in that there is a solitary and gregarious phase that may predominate in the population (Uvarov, 1928). These phases are differentiated by size, morphology and colour and may also vary by developmental stage. Solitary phase locusts are predominantly green, while those of the gregarious phase are primarily brown, yellow or black-grey with long, strong wings in the adult stage (Popov, 1989).

Locusts range across the African sahel, extending from the west coast of Africa south of the Sahara Desert to eastern Africa. The breeding range of migratory locusts encompasses the countries of Niger, Mali, Mauritania, Morocco, Algeria, Tunisia, Libya, Egypt, Sudan and Saudi Arabia. This region is characterized by unpredictable rainfall and is frequently ravaged by severe droughts (Talhouk, 1969). Successful reproduction during the winter and spring in these countries may result in large swarms that threaten sahelian countries and southwest Asia later in the summer. Other areas affected by invading locust swarms have included countries in northwest and eastern Africa, the Middle East and south-central Asia. If strong winds blowing northward over the Mediterranean Sea from Africa coincide with locust swarming, insects may be blown over southern Europe. Insects in these swarms usually die before dropping out of the sky on unsuspecting European locales.

Locusts may produce up to three generations per year. The first nymphs generally appear soon after winter or monsoon rains. They emerge either from eggs deposited in the ground the previous season by adults that died during the ensuing dry period, or from eggs laid at the beginning of the rainy period by adults that survived the dry period. The number of instars varies between five in males and six in females in the solitary, non-migratorial phase. Both males and females in the gregarious phase undergo five instars. Both species prefer wet and moderately humid habitats with heavy vegetation. Development of the gregarious phase is associated with the quality and quantity of vegetation and dispersal governed by prevailing weather conditions. Temperature and wind speed determine not only the presence or absence of flight activity, but also the distance flown per day. Migration does not start unless air temperature exceeds a critical threshold of 20° to 25°C. Transformation from the solitary phase to the gregarious phase gradually occurs in the population when locust density reaches about 10 to 20/m2.

Locusts are voracious plant feeders, with large swarms capable of devouring everything green in their path. However, a period of relative absence of locust swarms occurred from 1962 to 1986 (FAO, 1962). Swarms reappeared in 1987 and 1989 and remain a threat throughout most of their range (FAO, 1992, 1995).

The international scope of locust swarms has forced many regional and international organizations to work together to control them. Vegetation development in locust breeding grounds is monitored by ground and satellite surveys, and swarms are tracked by radar. Meteorological stations throughout the breeding and feeding range monitor weather conditions conducive to swarm formation and dispersal. The Food and Agriculture Organization of the United Nations (FAO) coordinates desert locust control and works with other regional and national programme organizations that implement control measures. Chemical control of locusts in breeding areas is the most widely used control method. It is also used when population surveys indicate that locust densities are rising. Ongoing research seeks to identify potential biological control agents, but at present no large-scale biological control programme is effective.

Wheat ground beetle

The wheat ground beetle, Zabrus tenebrioides Goeze (Coleoptera: Carabidae), also known as the corn ground beetle, is a pest widespread in the winter and spring wheat-growing areas of western and eastern Europe, western Asia, northern Africa and south-central Asia (Cate, 1980; Miller, 1991). Zabrus tenebrioides is especially serious in the western region of the Russia Federation, the Ukraine, Georgia and Turkey (Bonnemaison, 1980; Krazheva et al., 1981).

Adult wheat ground beetles are nondescript black beetles about 1.5 cm long. The black elytra extend completely over the abdomen and have several indented lines running lengthwise. The tibiae and tarsi may be yellowish-red to dark black. The larvae are yellowish-white with a blackish-brown head and thorax (Plate 69). Larvae may attain a length of up to 3 cm.

The wheat ground beetle is common throughout its range, but under normal conditions causes only occasional economic crop losses in localized areas. It is most damaging in areas where wheat or barley is grown in monoculture without fallow.

Adult beetles feed on sown seed and on the grains of developing ears. Larvae feed on leaves and stems of seedlings and on roots. Larvae pull the leaves underground and feed on them in a subterranean chamber, leaving a bare area where the seedling once stood. Fresh deposited soil of the burrowing insect is usually present at the soil surface. A single larva can eat about 25 wheat seedlings. Damage appears in the form of plantless gaps appearing within rows. Infestations of up to 50 larvae/m2 are common in fields where wheat is planted in monoculture over several years. With heavy infestations distributed throughout the field, economic crop loss may result within 7 to 14 days at normal spring temperatures. Zabrus tenebrioides rarely attacks non-cereal crops. Wireworms and scarab beetles cause damage that may be mistaken for that of Z. tenebrioides. Wireworms and white grubs feed on the roots and leave the dead, yellow seedling on the surface while Z. tenebrioides devours the entire seedling after pulling it underground (Plate 70).

The wheat ground beetle has a single generation per year in western Asia. Adults typically appear in May, June and July and feed at night, hiding under field debris during the day. Mating and oviposition occur in September following aestivation during the hot summer months. The eggs are laid singly in the soil at a depth of 15 to 18 cm. A single female can lay 40 to 80 eggs. Eggs hatch within two weeks if the soil is moist. Oviposition may be delayed until late fall under dry conditions. Adults die soon after oviposition. Larvae overwinter in the soil at depths of up to 40 cm. Damage to germinated seedlings is usually observable in late February. Pupation occurs in March. Adult emergence coincides with the milk stage of grain development over much of their geographic range.

Because adults and larvae feed on leaves and stems, foliar applications of insecticides are effective in controlling isolated outbreaks (Duran et al., 1975). Large-scale outbreaks can be almost completely eliminated by following a crop rotation programme that alternates cereals with a fallow or legume cover (Miller and Jones, 1997).

Ground pearls

The ground pearls, Porphyrophora tritici Bodenheimer and P. polonica L., are distributed throughout the moderate to low-rainfall wheat- and barley-growing areas of western and central Asia (Miller, 1991). The heaviest infestations have been reported from central and southern Turkey and from northern Syria (Duran, 1971).

Ground pearl eggs are very small and red, and are found in the soil encased within white, cottony wax filaments, hence the name ground pearls. The first instar is a small, reddish nymph measuring 0.5 to 2 mm long found between the leaf sheaths at the base of the plant. The insects' antennae are comprised of five segments each. The legs terminate in a single claw. The second instar is a cyst-like ball, red or purple in colour, legless and measuring 3 to 5 mm in diameter (Plate 71). It is found at the base of the plant and may or may not be covered by a leaf sheath. Adult females are oval-shaped, red in colour and measure 3 to 4 mm. Adult males are thin, cylindrical in shape, about 3 mm long, reddish in colour and possess wings.

Ground pearls most frequently attain pest status in areas planted continually to cereal monocultures in marginally arable land. As such, ground pearl outbreaks in the developing countries of the Middle East are often linked to the socio-economic condition of the farmers living on marginal land who commonly plant barley monocultures destined to feed their flocks of sheep. Ground pearls may be present, but usually are not economically serious pests in higher rainfall areas (more than 350 mm annual rainfall). They readily attack wheat plants in the absence of barley and may be transferred from place to place on farm equipment or on straw.

Ground pearls reduce the vigour of the plant by sucking plant fluids during the seedling stage of development. Infested plants are stunted and more susceptible to drought, disease and nematodes. In severe infestations, 80 to 100 percent of the plants may be infested with one or more insects, resulting in complete grain loss. In many instances, the remaining stunted stems and leaves may be grazed by sheep. Field studies have shown that a density of 12 insects per plant is sufficient to kill the plant.

Ground pearls can reproduce sexually and parthenogenetically. Eggs overwinter in cells in the soil. Eggs hatch and emergence occurs in December in the Middle East, whereupon the insects infest the plant, residing between leaves and the stalk and sometimes tunnelling down to the root collar. Cysts are formed following the first moult in early April concurrent with tillering. Adult females emerge from late May to June when heading occurs. Females remain under the soil and lay up to 300 eggs in a small chamber lined with wax threads. Males undergo a free pupal stage before becoming adults.

Ground pearls are readily controlled by rotating a clean fallow or legume cover crop between cereal plantings (Miller et al., 1994). Various soil insecticides are also effective, but usually are too expensive for farmers to use. Ground pearls rarely attain pest status in irrigated areas or in areas receiving greater than 300 mm rainfall.


Wheat stored as grain is subject to a number of insect and mite pests, many of which have developed cosmopolitan distributions over the years (Table 23.4). While a detailed description of these pests and methods of control is beyond the scope of this chapter, a few guidelines for proper grain storage that minimize many stored grain pest problems will be outlined.

TABLE 23.4
Some insects that attack stored grain


Scientific name




Sitrotroga cerealella (Olivier)

Angoumois grain moth; generally in warm areas; cosmopolitan


Corcyra cephalonica (Staint.)

Rice moth; cosmopolitan

Ephestia cautella Walker

Tropical warehouse moth; cooler areas; cosmopolitan

Ephestia elutella (Hübner)

Warehouse moth, tobacco moth; cooler areas; cosmopolitan

Ephestia kuhniella (Zeller)

Mediterranean flour moth; cosmopolitan

Plodia interpunctella Hübner

Indian meal moth; tolerates wide range of temperatures; South America, Europe, China

Pyralis farinalis L.

Meal moth; cosmopolitan



Rhyzopertha dominica (F.)

Lesser grainborer; cosmopolitan


Oryzaephilus surninamensis (L.)

Sawtoothed grain beetle; cosmopolitan

Cryptolestes ferrugineus (Stephens)



Sitophilus granarius (L.)

Granary weevil; cosmopolitan

Sitophilus oryzae (L.)

Rice weevil; cosmopolitan


Trogoderma granarium Everts

Khapra beetle; cosmopolitan; quarantined in the United States

Trogoderma glabrum Herbst

Grain beetle


Tenebrio molitor (L.)

Yellow mealworm; cosmopolitan

Tribolium castaneum (Herbst)

Red flour beetle; cosmopolitan; pest of flour mills

Tribolium confusum J. du Val

Confused flour beetle; cosmopolitan


Tenebrioides mauritanicus (L.)

Cadelle; cosmopolitan


Acarus siro L.

Flour mite

Glycyphagus destructor Schrank


Tyrophagus longior (Gervais)


Tyrophagus putrescentiae Schrank

Primarily in the tropics

Sources: Dyte, 1980; Champ and Dyte, 1976; Mamluk et al., 1992.

Proper storage involves ensuring that grain placed in storage is free from insects and then maintaining grain moisture and temperature at sufficiently low levels to inhibit insect activity and development. Because insects and mites are poikilothermic, low temperature decreases their metabolism and prohibits them from reproducing. In addition, many insects and mites have a threshold humidity below which they will not breed, will stay inactive or will die. Low temperature and low humidity also reduce the risk of fungal growth.

Processing and storage facilities should be kept free of pests through thorough cleaning and sanitation of equipment and storage spaces. Grain residues frequently are the source of reinfestation in mills and in storage facilities. Treatment of contaminated grain with appropriate chemicals, generally fumigants such as phosphine, or with non-residual insecticides prevents pest outbreaks. The methods or compounds employed are determined by the ultimate use of the grain. Grain destined for human or animal food must be free of any insecticide residues, while seed grain can be treated with more persistent insecticides. Grain is usually treated with insecticide as it enters the storage area on a conveyor belt.

Many insect species have developed resistance to frequently used pesticides. Insecticide resistance occurs when insects possessing a genetic ability to survive exposure to certain chemicals breed and pass on their genetically based tolerance to their offspring. Insecticide resistance can develop within a few generations and has rendered many formerly common insecticides ineffective (Champ and Dyte, 1976). Current research on stored product IPM seeks to develop biological and cultural control methods for managing pests.


The authors wish to thank Dr M. El Bouhssini and Dr S. Lhaloui for contributing information on Hessian fly and migratory locusts in Africa.


Aalbersberg, Y.K., Du Toit, F., van der Westhuizen, M.C. & Hewitt, P.H. 1987. Development rate, fecundity and lifespan of apterae of the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: aphididae), under controlled conditions. Bull. Entomol. Res., 77: 629-635.

Aalbersberg, Y.K., van der Westhizen, M.C. & Hewitt, P.H. 1988. Natural enemies and their impact on Diuraphis noxia (Mordvilko) (Homoptera: Aphididae) populations. Bull. Entomol. Res., 78: 111-120.

Araya, J.E., Quiroz, C. & Wellso, S.G. 1990. Pest status and control of the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: Aphididae). A review. West Lafayette, IN, USA, USDA/ARS and Purdue University.

Baker, C.A., Porter, D.R. & Webster, J.A. 1994. Registration of STARS-9302W and STARS-9303W, Russian wheat aphid resistant wheat germplasm. Crop Sci., 34: 1135-1136.

Bayoun, I.M., Plapp, F.W., Jr., Gilstrap, F.E. & Michels, G.A., Jr. 1995. Toxicity of selected insecticides to Diuraphis noxia (Homoptera: Aphididae) and its natural enemies. J. Econ. Entomol., 88: 1177-1185.

Bennany, S.A. & Riany, M. 1978. Resultats de quelques années d'essais pratiques de lutte chimique contre les cécidomyies des céréales du genre Mayetiola sp. Al Awamia, 55: 1-24.

Blackman, R.L. & V.F. Eastop, V.F. 1984. Aphids on the world's crops: an identification guide. New York, NY, USA, John Wiley and Sons.

Bonnemaison, L. 1980. Principal animal pests. In E. Hafliger, ed. Wheat, Documenta Ciba-Geigy, p. 59-68. Basle, Switzerland, CIBA-GEIGY.

Borror, D.J., Triplehorn, C.A. & Johnson, N.F. 1989. An introduction to the study of insects, 6th ed. Philadelphia, PA, USA, Saunders College Publishing.

Burnett, P.A. 1984. Cereal crop pests. In R.R. Scott, ed. New Zealand pest and beneficial insects, p. 153-166. Christchurch, New Zealand, Caxton Press.

Cardona, C., Hariri, G., El Haramein, F.J., Rashwani, A. & Williams, P.C. 1983. Infestation of wheat by suni bug (Eurygaster spp.) in Syria. Rachis, 2: 3-5.

Cate, P. 1980. Corn ground beetle (Zabrus tenebrioides Goeze) an important pest of grain in Austria [in German]. Der Pflanzenarzt., 33: 115-117.

Champ, B.R. & Dyte, C.E. 1976. Report of the FAO global survey of pesticide susceptibility of stored grain pests. FAO Plant Production and Protection Series No. 5.

Cox, T.S. & Hatchett, J.H. 1986. Genetic model for wheat/Hessian fly (Diptera: Cecidomyiidae) interaction: strategies for deployment of resistance genes in wheat cultivars. Environ. Entomol., 15: 24-31.

Cox, T.S. & Hatchett, J.H. 1994. Hessian fly-resistance gene H26 transferred from Triticum tauschii to common wheat. Crop Sci., 34: 958-960.

Cox, T.S., Hatchett, J.H., Gill, B.S., Raupp, W.J. & Sears, R.G. 1990. Agronomic performance of hexaploid wheat lines derived from direct crosses between wheat and Aegilops squarrosa. Zeitschrift fur Pflanzenzuchtung, 105: 271-277.

CSIRO. 1970. Insects of Australia. Carlton, Victoria, Australia, Melbourne University Press.

Debach, P. & Rose, M. 1977. Environmental upsets caused by chemical eradication. Calif. Agric., 31: 8-10.

Debach, P. & Rosen, D. 1991. Biological control by natural enemies. Cambridge, UK, Cambridge University Press.

Duran, M. 1971. Investigations on ground pearls [Margarodes (Porphyrophora) tritici Bodenheimer], a grain pest in central Anatolia [in Turkish with English summary]. In Bitki Koruma Bulteni, vol. 1, Suppl. 1. Ankara, Yeni Desen Matbaasi.

Duran, M., Altinaryar, G. & Koyuncu, N. 1975. Investigation on seed and soil treatments against the larvae of Zabrus spp. and Anisoplia spp. on cereals in Central Anatolia and phytotoxicity of lindane in field conditions [in Turkish]. Bitki Koruma Bulteni, 15: 202-224.

Dyte, C.E. 1980. Pests of stored wheat. In E. Hafliger, ed. Wheat, Documenta Ciba-Geigy, p. 75-78. Basle, Switzerland, CIBA-GEIGY., Switzerland.

El Einen, R.A., Bishara, S.I., Hariri, M.A., Youssef, G.S., Moneim, I.A. & Miller, R.H. 1989. Evaluating cereals for aphid resistance in Egypt. Arab J. Plant Prot., 7: 72-74.

El Heneidy, A.H., Abdel Shafi, A.M., Fayad, H. & Ashop, M. 1991 Monitoring of aphid populations and their natural enemies in sprayed wheat fields. In Annual Report of the Nile Valley Regional Program on Cool-Season Food Legumes and Cereals, p. 81-85. Giza, Egypt, ARC-FCRI.

El Heneidy, A.H., Ghannem, E.H., Fayad, Y.H. & Shoeb, M.A. 1992. Comparative population densities of aphids and their natural enemies in wheat fields at Middle and Upper Egypt. In Annual Report of the Nile Valley Regional Program on Cool-Season food Legumes and Cereals, p. 103-107. Giza, Egypt, ARC-FCRI.

Erdos, J. 1960. Fauna Hungariae, Chalci-doidea. Budapest, Akademici Kiado II. 205 pp.

FAO. 1962. Rapport d'une Réunion sur les Problèmes Meteorologiques Interessant le Projet Relatif au Criquet Pélerin, Rome, Oct. 1962.

FAO. 1992. Rapport de la Commission de Lutte contre le Criquet Pélerin en Afrique du Nord-Ouest, 18ième Session, Algers, 24-29 Oct. 1992.

FAO. 1995. Rapport de la 4ième Session du Groupe Technique sur le Criquet Pélerin, Rome, 21-24 Mar. 1995.

Flint, M.L. & van den Bosch, R. 1981. Introduction to integrated pest management, New York, NY, USA, Plenum Press

Gagné, R.J., Hatchett, J.H., Lhaloui, S. & El Bouhssini, M. 1991. Hessian fly and barley stem gall midge, two different species of Mayetiola (Diptera: Cecidomyiidae) in Morocco. Ann. Entomol. Soc. Amer., 84: 436-443.

Gerson, U. & Cohen, E. 1989. Resurgence of spider mites (Acari: Tetranychidae) induced by synthetic pyrethroids. Exp. Appl. Acarol., 6: 29-46.

Gilchrist, L.S., Rodriguez, R. & Burnett, P.A. 1984. The extent of Freestate Streak and Diuraphis noxia in Mexico. In P.A. Burnett & E. Cuellar, eds. Barley Yellow Dwarf. Proc. Workshop, 6-8 Dec. 1983, p. 157-163. Mexico, DF, CIMMYT.

Gilstrap, F., Bayoun, I. & Michels, A. 1992. The impact of RWA biological control: Some ideas on evaluating natural enemies in annual crop ecosystems. In W.P. Morrison, ed. Proc. 5th Russian Wheat Aphid Conf., Fort Worth, TX, USA, 26-28 Jan. 1992, p. 146-151. Great Plains Agricultural Council Publication 142.

Gould, F. 1991. The evolutionary potential of crop pests. Amer. Sci., 79: 496-507.

Haile, A. & Megenasa, T. 1987. Survey of aphids on barley in parts of Shewa, Welo and Tigrai, Ethiopia. Ethiop. J. Agric. Sci., 9: 39-53.

Hammon, R.W., Pearson, C.H. & Peairs, F.B. 1996. Winter wheat planting date effect on Russian wheat aphid (Homoptera: Aphididae) and a plant virus complex. J. Kan. Entomol. Soc., 69: 302-309.

Harlan, J.R. 1992. Crops and man. Madison, WI, USA, American Society of Agronomy, Crop Science Society of America.

Hatchett, J.H. & Gallun, R.L. 1970. Genetics of the ability of the Hessian fly, Mayetiola destructor, to survive on wheats having different genes for resistance. Ann. Entomol. Soc. Amer., 63: 1400-1407.

Hatchett, J.H. & Gill, B.S. 1983. Expression and genetics of resistance to Hessian fly in Triticum tauschii (Coss) Schmal. In Proc. 6th International Wheat Genetics Symp., p. 807-811. Kyoto, Japan, Kyoto University.

Hewitt, P.H. & Kriel, V.P. 1984. The noxious wheat aphid Diuraphis noxia (Mordvilko). A new major pest in southern Africa. In Proc. 17th Int. Cong. Entomology. Hamburg, Germany.

Hill, B.D., Butts, R.A. & Schaalje, G.B. 1996. Factors affecting chlorpyrifos activity against Russian wheat aphid (Homoptera: Aphididae) in wheat. J. Econ. Entomol., 89: 1004-1009.

Hille Ris Lambers, D. 1975. Observaciones sobre el problema de los áfidos en Chile. Informe de la visita a Chile del Dr. D. Hille Ris Lambers del 6-XI al 4-XII 1974. Concepcion, Chile, Esc. de Agron., Univ. de Concepcion. 21 pp.

Hopper, K.R., Lacey, L.A., Kazmer, D.J., Chen, K., Coutinot, D., Mercandier, G., Kirk, G. & Noel, V. 1992. Biology, ecology, and collection of natural enemies of the Russian wheat aphid. Behoust, France, Mimeo Rep., USDA/ARS European Parasite Lab.

Hopper, K.R., Coutinot, D., Chen, K., Kazmer, D.J., Mercadier, G., Halbert, S.E., Miller, R.H., Pike, K.S. & Tanigoshi, L. 1998. Exploration for natural enemies to control Diuraphis noxia in the United States. In S.S. Quisenberry & F.B. Peairs, eds. Response Model for an Introduced Pest - The Russian Wheat Aphid. Proc. Thomas Say Publications in Entomology. Lanham, MD, USA, Entomology Society of America.

Huffaker, C.B., van den Brie, M. & McMurtry, J.A. 1969. The ecology of tetranychid mites and their natural control. Ann. Rev. Entomol., 14: 125-174.

Huffaker, C.B., van den Brie, M. & McMurtry, J.A. 1970. The ecology of tetranychid mites and their natural enemies: a review. II. Tetranychid populations and their possible control by predators: an evaluation. Hilgardia, 40: 391-458.

Hughes, R.D. & Maywald, G.F. 1990. Forecasting the favourableness of the Australian environment for the Russian wheat aphid, Diuraphis noxia (Homoptera: Aphididae), and its potential impact on Australian wheat yields. Bull. Entomol. Res., 80: 165-175.

Javahery, M. 1996. Sunn pest of wheat and barley in the Islamic Republic of Iran: chemical and cultural methods of control. In R.H. Miller & J.G. Morse, eds. Sunn pests and their control in the Near East. FAO Plant Prod. Prot. Paper No. 138, pp. 61-74. Rome, FAO.

Kannan, H.O. 1992. Investigations in pest problems in wheat at rahad. In Annual Report of the Nile Valley Regional Program on Cool-Season food Legumes and Cereals, p. 161-172. Giza, Egypt, ARC-FCRI.

Kozlov, M.A. & Kononova, S.V. 1983. Telenominae of fauna of the USSR (Hymenoptera, Scelionidae). Leningrad, Nauka Publisher. 351 pp.

Krazheva, L.P., Pnomareva, E.A. & Chikhacheva, U.N. 1981. Protection of wheat from the carabid beetle Zabrus tenebrioides, USSR. Zashchita Rastenii, 7: 44-45.

Lara, S. & Zuniga, E. 1969. Metopolophium dirhodum (Walker) Homoptera, Aphididae, afido nuevo para Chile importante plaga del trigo. Simiente (Chile), 5(1-3): 34-36.

Lhaloui, S. 1995. Biology, host preference, host suitability, and plant resistance studies of the barley stem gall midge and Hessian fly (Diptera: Cecidomyiidae) in Morocco. Ph.D. thesis. Manhattan, KS, USA, Entomology Department, Kansas State University. 184 pp.

Lhaloui, S., L. Buschman, L., El. Bouhssini, M., Starks, K., Keith, D. & El Houssaini, K. 1992. Control of Mayetiola species (Diptera: Cecidomyiidae) with carbofuran in bread wheat, durum wheat, and barley with yield loss assessment and its economic analysis. Al Awamia, 77: 55-73.

Lin, B.H., Padgitt, M., Bull, L., Delvo, H., Shank, D. & Taylor, H. 1995. Pesticide and fertilizer use and trends in U.S. agriculture. Agricultural Economic Report No. 717. Washington, DC, Economic Research Service, USDA.

Mamluk, O.F., Tahhan, O., Miller, R.H., Bayaa, B., Makkouk, K.M. & Hanounik, S.B. 1992. A checklist of cereal, food legume and pasture and forage crop diseases and insects in Syria. Arab. J. Plant Prot., 10: 225-166.

Martin, T.J. & Harvey, T.L. 1995. Registration of two wheat germplasms resistant to Russian wheat aphid: KS92WGRC24 and KS92WGRC25. Crop Sci., 35: 292.

McMurtry, J.A., Huffaker, C.G. & van den Brie, M. 1970. Ecology of tetranychid mites and their natural enemies: a review. I. Tetranychid enemies: their biological characters and the impact of spray practices. Hilgardia, 40: 331-390.

Metcalf, R.L. 1982. Insecticides in pest management. In R.L. Metcalf & W.H. Luckmann, eds. Introduction to insect pest management, 2nd ed., p. 217-277. New York, NY, USA, John Wiley and Sons.

Meyerdirk, D.E. 1989. Russian wheat aphid. A report to the National Association of State Departments of Agriculture. 15 pp.

Miller, R.H. 1991. Insect pests of wheat and barley in West Asia and North Africa. Technical Manual 9 (rev. 2). Aleppo, Syria, ICARDA. 136 pp.

Miller, R.H. 1994. IPM in the Nile Valley. In D.A. Saunders & G.P. Hettel, eds. Wheat in heat-stressed environments: irrigated, dry areas and rice-wheat farming systems, pp. 109-120. Mexico, DF, CIMMYT.

Miller, R.H. & Ghannoum, M.I. 1994. Current distribution of wheat and barley insects in Syria and some implications for cereal pest management. Arab J. Plant Prot., 12: 80-82.

Miller, R.H. & Jones, M.J. 1997. Fluctuation in a population of ground pearls, Porphyrophora tritici (Bodenheimer) (Homoptera: Margarodidae), in barley in northern Syria. Rachis, 16: 84-85.

Miller, R.H. & Morse, J.G., eds. 1996. Sunn pests and their control in the Near East. FAO Plant and Protection Series No. 138. 165 pp.

Miller, R.H., Youssef, G.S., Sahfi-Ali, A.M. & El Sayed, A.A. 1992. Host-plant resistance to aphids in three Nile Valley countries. In A. Comeau & K. Makkouk, eds. Barley Yellow Dwarf in West Asia and North Africa, Rabat, 19-21 Nov. 1989, p. 147-152. Aleppo, Syria, ICARDA. 239 pp.

Miller, R.H., Pike, K.S, Tanigoshi, L.K, Buschman, L.L. & Kornosor, S. 1993. Distribution and ecology of the Russian wheat aphid, Diuraphis noxia Mordvilko (Homoptera: Aphididae) in western Asia and northern Africa. Arab J. Plant Prot., 11: 45-52.

Miller, R.H., Harris, H.C. & Jones, M.J. 1994. Crop rotation effects on populations of Porphyrophora tritici (Bodenheimer) (Homoptera: Margarodidae) in barley in northern Syria. Arab. J. Plant. Prot., 12: 79-75.

Mossad, M.G., Shafi, A.A. & Miller, R.H. 1992. Aphid damage and resistance in wheat in Egypt.. In A. Comeau & K. Makkouk, eds. Barley Yellow Dwarf in West Asia and North Africa, Rabat, 19-21 Nov. 1989, p. 139-146. Aleppo, Syria, ICARDA. 239 pp.

NRC. 1996. Ecologically based pest management: new solutions for a new century. National Research Council Committee on Pest and Pathogen Control Through Management of Biological Control Agents and Enhanced Cycles and Natural Processes, National Academy of Sciences. Washington, DC, National Academy Press.

Osteen, C.D. & Szmedra, P.I. 1989. Agricultural pesticide use trends and policy issues. Agricultural Economic Report No. 622. Washington, DC, USDA.

Paulian, F. & Popov, C. 1980. Sunn pest or cereal bug. In E. Hafliger, ed. Wheat, Documenta Ciba-Geigy, p. 69-74. Basle, Switzerland, CIBA-GEIGY.

Pike, K.S., Starý, P., Miller, T., Allison, D., Boydston, L. & Graf, G. 1999. Host range and habitats of the aphid-parasitoid Diaeretiella rapae (M'Intosh) (Hym.: Aphidiidae) in Washington State. Environ. Entomol., 28: 61-71.

Popov, C. 1979. General considerations on the ecological factors involved in the regulation of pest population levels in cereal crops. Prob. Prot. Plant., 7: 401-423.

Popov, C. 1985. Studies on the influence of the fat body on the survival of Eurygaster integriceps Put. during diapause. An. Inst. Cercet. Cereal Plant Tech., (Fundalea) 52: 335-339.

Popov, G.B. 1989. Nymphs of the Sahelian grasshoppers: an illustrated guide. Chatham, UK, Overseas Development Natural Resources Institute. 158 pp.

Quisenberry, S.S. & Schotzko, D.J. 1994. Russian wheat aphid (Homoptera: Aphididae) population development and plant damage on resistant and susceptible wheat. J. Econ. Entomol., 87: 1761-1768.

Rafi, M.M., Zemetra, R.S. & Quisenberry, S.S. 1996. Interaction between Russian wheat aphid (Homoptera: Aphididae) and resistant and susceptible genotypes of wheat. J. Econ. Entomol., 89: 239-246.

Rassipour, A., Gadjabi, G. & Esmaili, M. 1996. The Islamic Republic of Iran. In R.H. Miller & J.G. Morse, eds. Sunn pests and their control in the Near East. FAO Plant Prod. Prot. Paper No. 138, p. 85-90. Rome, FAO.

Rechmany, N., Miller, R.H., Traboulsi, A.F. & Kfoury, L. 1993. The Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Homoptera: Aphididae), and its natural enemies in northern Syria. Arab J. Plant Prot., 99: 92-99.

Reed, D.K. & Pike, K.S. 1990. Biological control exploration in Brazil, Argentina, and Chile for natural enemies of Russian wheat aphid, Diuraphis noxia. USDA-ARS Trip Report, 27 Oct.-19 Nov. 1990. Stillwater, OK, USA, USDA-ARS, Plant Sci. Res. Lab.

Remaudière, G. & Remaudière, M. 1997. Catalogue des Aphididae du monde. Paris, INRA. 473 pp.

Rosca, I., Popov, C., Barbulescu, A., Vonica, I. & Fabritius, K. 1996. The role of natural parasitoids in limiting the level of sunn pest populations. In R.H. Miller & J.G. Morse, eds. Sunn pests and their control in the Near East. FAO Plant Prod. Prot. Paper No. 138, p. 35-45. Rome, FAO.

Safavi, M. 1968. Etude biologique et écologique des Hymenoptères des oeufs des punaises des cereales. Entomophaga, 13: 381-485.

Sanderson, E.D. 1915. Insect pests of farm, garden and orchard. New York, NY, USA, John Wiley and Sons.

Sharaf El Din, N. 1992. Investigations into aphid problems on wheat. In Annual Report of the Nile Valley Regional Program on Cool-Season Food Legumes and Cereals, p. 173-186. Giza, Egypt, ARC-FCRI.

Sharaf El Din, N. & Kannan, H.O. 1994. Pest problems of wheat in Sudan. In D.A. Saunders & G.P. Hettel, eds. Wheat in heat-stressed environments: irrigated, dry areas and rice-wheat farming systems, pp. 121-126. Mexico, DF, CIMMYT.

Simsek, Z., Memisoglu, H. & Salcan, Y. 1996. Turkey. In R.H. Miller & J.G. Morse, eds. Sunn pests and their control in the Near East. FAO Plant Prod. Prot. Paper No. 138, p. 133-141.

Skaf, R. 1996. Sunn pest problems in the Near East. In R.H. Miller & J.G. Morse, eds. Sunn pests and their control in the Near East. FAO Plant Prod. Prot. Paper No. 138, p. 9-15. Rome, FAO.

Srivastava, J.P., Miller, R.H. & van Leur, J.A.G. 1988. Biotic stress in dryland cereal production: the ICARDA perspective. In P.W. Unger, W.R. Jordan, T.V. Sneed, & R.W. Jensen, eds. Challenges in Dryland Agriculture, a Global Perspective. Proc. Int. Conf. Dryland Farming, Amarillo, TX, USA, p. 908-909. Texas Agric. Exp. Sta.

Starý, P. 1995. The Aphidiidae of Chile (Hymenoptera, Ichneumonoidea, Aphidiidae). Dtsch. Entomol. Z., N.F., 42: 113-138.

Starý, P., Gerding, M., Norambuena, H. & Remaudière, G. 1993. Environmental research on aphid parasitoid biocontrol agents in Chile (Hym., Aphidiidae; Hom., Aphidoidea). J. Appl. Entomol., 115: 292-306.

Stern, V.M., Smith, R.F., van den Bosch, R. & Hagen, K.S. 1959. The integrated control concept. Hilgardia, 29: 81-101.

Talhouk, A.M. 1969. Insects and mites injurious to crops in Middle Eastern countries. Monographien zur Angewandte Entomologie No. 21. Hamburg, Germany, Verlag Paul Parey.

Tammam, A.M. & Towfelis, M.B. 1992. Assessment of aphid tolerance in bread and durum wheat. In Annual Report of the Nile Valley Regional Program on Cool-Season Food Legumes and Cereals, p.119-123. Giza, Egypt, ARC-FCRI.

Tanigoshi, L.K., Pike, K.S., Miller, R.H., Miller, T.D. & Allison, D. 1995. Search for, and release of, parasitoids for the biological control of Russian wheat aphid in Washington State (USA). Agric. Accuses. Environ., 52: 25-30.

Uvarov, B.P. 1928. Locusts and grass-hoppers. A handbook for their study and control. London, Imperial Bureau of Entomology.

van den Bosch, R. 1976. Informe sobre el control biológico de los áfidos de los cereales en Chile. Agric. Técn. (Chile), 36: 141-145.

Voegelé, J. 1996. Review of biological control of sunn pest. In R.H. Miller & J.G. Morse, eds. Sunn pests and their control in the Near East. FAO Plant Prod. Prot. Paper No. 138, p. 23-33. Rome, FAO.

Walters, M.C., Penn, F.F., Du Toit, F., Both, T.C., Aalbersberg, K., Hewitt, P.H. & Broodryk, S.W. 1980. The Russian wheat aphid. In Farming South Africa Leaflet Series, Wheat G3, p. 1-6.

Youssef, G.S., Ghanem, E.H. & Marzouk, I.A. 1992a. Screening for resistance against Schizaphis graminum of some wheat lines and Aegilops species. In Annual Report of the Nile Valley Regional Program on Cool-Season Food Legumes and Cereals, p. 114-118. Giza, Egypt, ARC-FCRI.

Youssef, G.S., Hariry, M. & Ghanem, E.H. 1992b. Yield assessment of some wheat lines with various levels of resistance to the aphid Rhopalosiphum padi. In Annual Report of the Nile Valley Regional Program on Cool-Season Food Legumes and Cereals, p. 108-113. Giza, Egypt, ARC-FCRI.

Zillinsky, F.J. 1983. Common diseases of small grain cereals: a guide to identification. Mexico, DF, CIMMYT.

Zuniga, E. 1990. Biological control of cereal aphids in the southern cone of South America. In P.A. Burnett, ed. World perspectives on barley yellow dwarf, p. 362-367. Mexico, DF, CIMMYT.

Previous Page Top of Page Next Page