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Chapter 5
Pests and Diseases

Entomological Observations

Geraldo Pereira de Arruda
Professor, Biology Department

Eneide Carvalho de Arruda
Associate Professor, Biology Department

Arlene Bezerra Rodrigues dos Santos
Assistant Professor, Biology Department

Auristela Correira de Albuquerque Holanda
Assistant Professor, Biology Department
Universidade Federal Rural de Pernambuco

Sawyers and Borers (Coleoptera, Cerambycidae) of P. juliflora

The first reports regarding damage to P. juliflora (Sw) dc by insects in Pernambuco date from 1956 and 1957, according to Carvalho et al. (1968), as a natural result of the expansion of the areas planted with this species.

As from 1960, an insect that sawed off the P. juliflora branches started to attract attention, becoming known in Brazil as “algarobeira sawyer.”

Material Collection

With the increase in the occurrence of this insect in Pernambuco, research was initiated in 1968 on insects associated with P. juliflora.

The material collected initially consisted of branches sawn-off by this insect, wherein its young forms develop, for study in laboratory. The material was placed in growth chambers so that the insects would evolve completely.

In addition to the “sawyer” insect, adult forms of other beetle species also emerged from the material collected in the field and raised in laboratory.

Beetles Collected on P. juliflora

To date, the following beetles were collected and identified on P. juliflora in Pernambuco:

  1. Aorcadocerus barbatus (Coleoptera, Cerambycidae)
  2. Coccoderus novempunctatus (Germar, 1824) (Coleoptera, Cerambycidae)
  3. Neoclytus rufus (Oliv., 1795) (Coleoptera, Cerambycidae)
  4. Neosozineus griseolus (Hoffm., 1984) (Coleoptera, Cerambycidae)
  5. Oncideres limpida Bates, 1865 (Coleoptera, Cerambycidae)
  6. Oreodera quinquetuberculata (Drapier, 1820) (Coleoptera, Cerambycidae)
  7. Trachyderes thoraxicus (Oliv., 1790) (Coleoptera, Cerambycidae)

All the beetles found in P. juliflora belong to the family Cerambycidae, easily recognizable for their general body form and for the extraordinary length of the antennas, always longer than the insect itself.

Results

The collection, raising and identification of the beetles associated with P. juliflora showed that the most damaging and most widespread insect is Oncideres limpida, locally known as “P. juliflora sawyer” or, in Portuguese, “serrador da algarobeira.” Other species behave as borers (Coleobroca); they do not saw off the branches, but their larvae kill them by boring galleries where they will then develop; some of these species can even kill the whole plant.

O. novempunctatus also presents a sawing behavior, but with a very low to negligible occurrence index.

O. thoraxicus bores through fallen or dry branches, thereby not causing damage to the plant and being considered secondary occurrence.

The remaining species bore through the branches, occurring as well on the stem and causing minor damage.

Observations Regarding Oncideres limpida (Coleoptera, Cerambycidae)

The “sawyer” Oncideres limpida Bates, 1865 (Coleoptera, Cerambycidae) was found cutting into P. juliflora branches in the district of Surubim, Pernambuco, in 1956 and 1957, according to Carvalho et al. (1968). The insect has now been detected in Pernambuco and neighboring states. In Pernambuco, O. limpida was collected in the following townships: Arcoverse, Bom Jardim, Carpina, Caruarú, Gravatá, Limoeiro, Pedra, Pesqueira, São Caetano, Surubim, Taquaritinga do Norte, Venturosa and Vertentes.

In 1968, technicians with the Agriculture Department of the State of Pernambuco expreseed their concern about the seemingly widespread occurrence of an insect labelled “sawyer,” evidenced by the sizable number of sawn off branches from P. juliflora alongside Highway br-132, in the area extending from Gravatá to Caruarú. At the São Caetano district, this insect occurred in great numbers during 1968–1969, being even considered as an obstacle against cultivation of P. juliflora, as the insect sawed off plants around 1.50 m in height.

At present, it is considered as the most damaging insect affecting P. juliflora in Pernambuco.

Insect Identification

The “sawyer” was identified as Oncideres limpida Bates, 1865 (Coleoptera, Cerambycidae). The insects belonging to the family Cerambycidae are commonly referred to as “sawyers” or, in Brazil, “serradores” or “serra-pau.” O. limpida, as a result of occurring on P. juliflora, became known as the “algarobeira sawyer.”

O. limpida, the “sawyer” of P. juliflora.

Insect Behavior

O. limpida damages the plant by sawing off branches, a behavior conditioned by reproduction. The females lay their eggs on the branches, and thereafter start cutting into them near the base until they fall. Juvenile forms of the insect are born from the eggs and develop within the galleries they themselves bore through the dry branches.

Once its development has been completed, the larva goes into pupa stage in a wider cavity it has previously bored. After a rather long period, the pupa gives rise to an adult insect.

Female O. limpida carry out their reproductive activity during the rainy season (Northeastern winter), when mating, egg laying and branch sawing take place.

During the dry period (Northeastern summer), this insect practically disappears, being found only as juveline forms within the sawn-off branches.

Control

According to Carvalho et al. (1968), “the ideal way to combat this insect would be through biological control, using some natural enemy which, attacking the parasite either at larva or nymph stage, could check its spread and keep its numbers at a level that does not pose a threat to P. juliflora.

One technique recommended by Carvalho et al. (1968) is to collect sawn-off P. juliflora branches and burn them, thereby destroying the insect's young forms and preventing their multiplication.

Branch collection and burning must be carried out during the dry season, so as to avoid the appearance of the insect when the rains come. This technique contributes to reducing the population of this insect in the area.

A Parasite to Oncideres limpida (Coleoptera, Cerambycidae)

Dry pupas of Oncideres limpida Bates, with cylindrical holes characteristic of parasitic activity were found in material collected alongside Highway BR-111, between the townships of Bezerros and Caruarú, in dry sawn-off branches where the sawyer insect was undergoing the pupa stage.

The study of natural enemies (parasites) of Oncideres limpida is of great importance in the region, as this sawing insect is one of the most damaging insects affecting P. juliflora in Pernambuco.

This parasite can be used in a biological war against the O. limpida pest, as a control alternative.

Collection

Initial observations of possible occurrence of parasites to O. limpida in immature stage, were made on pupas presenting dark coloration instead of the normal milky white. The first hypothesis raised was occurrence of an entomogenic fungus.

The examination of further samples collected from P. juliflora with numerous branches sawn off by O. limpida produced dry pupas with round orifices suggesting the presence of the parasite.

Hymenoptera found as a parasite to O. limpida.

New samples were collected and part of the material was placed in emersion boxes; eventually, a black microhymenoptera emerged. It was identified as a Hymenoptera, Chalcidoidea. The Hymenoptera of this group are capable of becoming parasites to insects growing inside plants, as is the case of O. limpida.

The parasites found are being studied for a complete identification and subsequent use.

P. juliflora Pod Borer Found at Pernambuco (Coleoptera, Anobiidae)

In Pernambuco, at the Agreste region, a beetle was found boring seeds in ripe pods still attached to the plant. The insect is a coleohorn which might become a problem for P. juliflora plantations.

This brown-colored insect belongs to the family Anbiidae, is less than half a centimeter in length and has saw-like antennas.

Material collection

One of the puzzling facts was the presence of this insect in ripe P. juliflora pods still attached to the tree.

Ripe pods showing dark stains (a sign of some anomaly) were collected by picking them both directly from the tree and up from the ground.

The material collected was placed in emersion boxes in order to capture the insects that might be growing within the pods.

Small brown beetles, less than half a centimeter in length, eventually emerged from the pods.

Results

The insect was identified as belonging to the genus Lasioderma (Coleoptera, Anobiidae).

Lasioderma sp., borer of P. juliflora pods.

Beetles from the family Anobiidae are characterized by their oval-shaped body, antennas located ahead of the eyes, normally small, brown to dark brown in color. They are generally xylophagous and those with major economic impact occur in manufactured substances of either plant or animal origin.

The Lasioderma sp. found in Pernambuco bores through P. juliflora pods, destroying them. Both its numbers and area of distribution have been increasing lately, with potential of becoming a major pest which might constitute a constraining factor for seed production.

Occurrence of the Cochineal Insect Asterolecanium pustulans
(Homoptera, Asterolecaniidae) in P. juliflora

In the Pedra district, Pernambuco, a cochineal insect was found thriving on the stem of a P. juliflora plant, covering a large portion of both stem and branches. No damage or symptoms have so far been observed which could point to this insect as responsible for a pest affecting P. juliflora. This same cochineal insect, in other plants, is capable of even killing the host when the infestation is great, as in the case of fig trees.

The insect proliferates on the stem, attaching itself to it and resembling pustules, at the center of which sits a yellow-greenish scale-like insect.

Collection

The occurrence of this cochineal insect on a plant is evidenced by what looks like an accumulation of yellow dots. In the adult stage, this insect is deprived of movement, remaining attached to a certain point where it forms colonies.

P. juliflora branch infested with A. pustulans.

Collection is made by removal of insect-infested portions. Examination of the material is possible only with optical equipment (stereoscope), as the insect is very small; its characteristics can only be detected with the insect mounted on a slide.

Identification

The cochineal insect found on P. juliflora was identified as Asterolecnium pustulans (Cockerell, 1892) (Homoptera, Asterolecaniidae), which occurs in great numbers on the stem of several crop plants.

The P. juliflora trees affected by A. pustulans do not evidence symptoms of damage, suggesting that the plants might possess certain resistance against the insect.

References

arruda, e.c. de, and arruda, g.p. de, 1971: “Nocões fundamentais sobre algumas pragas de plantas cultivadas no Estado de Pernambuco,” Instituto de Ciencias Biológicas, Universidade Federal Rural de Pernambuco, Impresa Universitária, Recife, 124 p.

borror, d.j. and delong, d.m., 1969: “Estudo dos Insetos,” Programa de publicacões didáticas, Agencia Norte-Americana para o Desenvolvimento Internacional - usaid, Rio de Janeiro, 653 p.

carvalho, m.b. de; carvalho, e.p. de and arruda, g. de, 1968: “O «serrador», praga da algarobeira,” Instituto de Pesquisa Agronomica de Pernambuco, Boletim Técnico No. 33, Recife, 27 p.

lima, a. da Costa, 1942: “Insetos do Brasil,” Vol. 3, Homópteros, Escola Nacional de Agronomia, Série Didática No. 4, Rio de Janeiro, pp. 240–246.

lima, a. da Costa, 1953: “Insetos do Brasil,” 2nd. part, Escola Nacional de Agronomia, Série Didáctica No. 10, Rio de Janeiro, pp. 227–229.

lima, a.c. da, 1955: “Insetos do Brasil,” Coleópteros, 3rd part, Escola Nacional de Agronomia, Série Didática No. 11, Rio de Janeiro, pp. 92–141.

mendes, b.v., 1985: “Alternativas tecnológicas para a agropecuária do semi-árido,” Nobel, Rede Globo - Projecto Nordestino, São Paulo, p. 171.

silva, a.s. et al., 1986: “Orientacões básicas sobre a cultura da algarobeira,” Empresa de assistencia Técnica e Extensão Rural do Estado de Pernambuco, emater, Recife, p. 19.

silva, a.g. d'A et al., 1968: “Quarto catálogo dos insetos que vivem nas plantas do Brasil, seus parasitos e predadores,” Part II - Vol. i, Serviço de Defesa Sanitária Vegetal, Laboratório Central de Patologia Vegetal, Rio de Janeiro, pp. 383–412.

Utilization of P. juliflora as Culture Medium and as Enriching Source for Phytopathogenic Fungi Culture

Gilvan J. C. Santos
Professor, Forestry Department
Universidade Federal de Pernambucol cstr, Campus VII

Maria do Socorro V. Pereira
Professor, Veterinary Medicine Department
Universidade Federal de Pernambucol cstr, Campus VII

Introduction

The creation of both natural and synthetic culture media for the study of fungi has been intense and dates from the times of Pasteur (1859).

P. juliflora (Sw) dc, in addition to being rich in energy, offers some 9.91% in crude protein; the flesh of its fruit presents high content of saccharose, calcium, phosphorus, iron, vitamin B1 and B6, affording it high nourishing value. With these properties in mind and the nutritional requirements of fungi, the formulation of a culture medium was attempted, considering also the easy availability of this species in the Northeast, particularly at the semi-arid region of Paraíba.

Barbosa (1977) found the following values for dry P. juliflora pods: 82.7% dry matter; 9.91% crude protein; 0.83% ether extract; 54.16% soluble carbohydrates; 25.9% cell wall constituents; 37.6% ash (mineral residue); 0.16% calcium, and 0.13% phosphorus. Analyses performed at the Animal Nutrition Laboratory of ipa/Pernambuco Agriculture & Livestock Research Agency, found pod composition as shown in Figure 1.

The objectives of this work were, therefore: a) to study the influence of P. juliflora on phytopathogenic fungi growth; b) to replace dextrose used in bda (Batata Dextrose agar - Potato Dextrose agar) for baa (Batata Algaroba agar - Potato P. juliflora pod agar), comparing the development of the fungi in each of the two culture media; c) to test P. juliflora pods as culture medium (aa).

Figure 1

Figure 1. Bromatologic analysis of Prosopis juliflora pods.

Material and Methods

The material used was P. juliflora (Sw) dc pods, basing on the experiments by Burkart (in Carvalho, 1961), which stated that “the flesh of P. juliflora pods contains 62.7% of soluble sugars and accounts for 74% of total fruit weight; thus, 100 kg of pods produce 46.4 kg of sugar.” Calculations for substituting Dextrose in bda were based on this experience.

The culture media were made up as follows:

bda  
Potato200g
Dextrose20g
Agar15g
Distilled water1,000ml
   
baa  
   
Potato200g
Agar 15 g  
P. juliflora pod broth150ml
Distilled water1,000ml
   
aa  
   
Agar15g
P. juliflora pod broth150ml
Distilled water1,000ml

The P. juliflora pods were crushed with a fodder machine, with the purpose of utilizing them thoroughly. The material was then decocted and sifted, adding previously calculated amounts of the resulting broth to molten agar with decoction of English potato. Once the media were ready, pH was measured, finding 7.0 (neutral pH). The culture media were distributed in test tubes and then placed in autoclave. After sterilization in oven at 37° C, placing of phytopathogenic fungi was performed to observe growth. Fungal growth and development assessments were started 48 hours after placing them in the media.

Results and Discussion

The observations made after placing the fungi showed the efficacy of P. juliflora pods as an enriching source and as a replacement for Dextrose in bda (Batata Dextrose agar - Potato Dextrose agar), demonstrating as well their efficacy for phytopathogenic fungus development in a culture medium containing solely P. juliflora pods as nutrient source.

In baa culture medium, faster growth was observed 48 hours after placing in medium; in aa culture medium, growth was slower as compared with bda and baa, but with good fungal development.

As regards fungal behavior, Sclerotium rolfsii and Sclerotium coffeicullum in bda showed dark and light brown coloring faster than in baa or aa.

No special features were observed regarding the remaining fungi, Cryphonectria cubensis, Pestalotia sp., Fusarium sp., Trichoderma sp. and Helminthosporium sp., as their growth was not particularly outstanding in the above media.

References

azevedo, c. f., 1984: “Algarobeira na alimentação animal e humana,” In: I Simpósio Brasileiro Sobre Algaroba, Natal-rn, 1982, Trabalhos-Natal, emparn, pp. 283–287.

franco, h. f., 1984: “Adapta-se ao Semi-árido e é boa para quase tudo,” In: Revista Brasileira de Extensão Rural, Brasília, 5 (2): 7–11.

galli, i. et al., 1978: “Manual de Fitopatologia,” 2nd Ed., São Paulo, Agronomica Ceres, Vol. 2.

silveira, v. d., 1981: “Micrologia,” 3rd Ed., Rio de Janeiro, Interamericana, 332 p.


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