Benign lethality: Tools for crop protection
Noted & noteworthy
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Successful pest control has played an essential part in achieving the massive yield increases of the past 30 years, in both the Northern industrialized countries and the developing South. And chemical pesticides have been the leading tool. Without them, we'd likely never have seen the North's over-abundance of wheat and maize, or the Green Revolution that made at least some countries in the South self-sufficient in food.
But the price has been high, some say prohibitively so: water pollution, human deaths and suffering, damage to biodiversity, rising costs, and increasing farmer dependence on expensive imports. Pesticide use has generally not been appropriate for subsistence farmers on marginal lands, and any "trickle- down" effects (to borrow a term from Reaganomics) from their larger neighbors' use of such compounds have generally been damaging. The relative few smallholders who can afford pesticides are often so impressed by the spectacular initial reduction of damage to their crops that they are tempted to use more and more chemicals, wasting precious capital while simultaneously creating groundwater toxicity problems. Frequently, spraying equipment is badly maintained, chemicals long abandoned in the North for health reasons are still available in the South, and farmers are too often unable to read instructions or warnings on pesticide containers printed in languages they don't understand.
This is not to say that pesticides should be condemned out of hand. There is a place for their use, together with other measures, in any Integrated Pest Management (IPM) program. However, considerable knowledge, which many smallholders lack, is required for their safe and efficient use.
Less dangerous are the many biological, mechanical and systems - planning pest control methods - some of them based on long tradition and some quite new - discussed in this valuable book from England's well-known Intermediate Technology Group.
Sufficient detail
Editor Miguel Altieri makes some useful observations on the contents of the IPM toolbox, from letting ducks and geese do the work mechanically to the tedious, but very effective, method of injecting maize on the cob with pesticide. He, like the book's other contributors, describes these practices in enough detail for the reader to fully understand them and put them into practice where appropriate. Too many books introduce ideas which are of little use unless you are lucky enough to have access to the references at the end of each chapter. This book, although it does have an extensive bibliography, tells readers how things are done.
Estimates of losses due to insect pests vary from 10 to 30 per cent of a total crop in many regions. But the mere presence or absence of pests isn't always the key factor. Insect density can be less important than poor plant nutrition, the presence of weeds, adverse weather and other stresses that make plants more susceptible to insect invasion.
The latter may vary more from field to field than from year to year, but some farmers, seeing a few in- sects which their crop might be able to withstand naturally, spray unnecessarily.
In traditional farming practice, rotation and intercropping, apart from their other advantages, have played an important role in pest and weed control. Exactly what are weeds is a moot point. In maize fields in Mexico, local farmers recognize some 40 different "weeds," half of which they consider "bad weeds" and the other half "good weeds," useful as food, fodder, medicines, soil conditioners or other purposes. Some also serve as hosts to the natural enemies of pests and as such should be maintained. Blanketing a field with chemical pesticide or herbicide, as advocated by proponents of high-intensity monocropping, would kill the good as well as the bad.
Fish, which eat insects and their larvae, can also be part of the IPM arsenal, and raising fish in flooded rice fields dates back 2 000 years in China. Worked into the annual rotation, a "crop" of fish helps control pests, while providing a supplement to the farmer's diet and a potential cash crop, as well. Fish faeces pro- vide nutrients for the rice plants, and the movement of fish aerates the water. But this practice was in- compatible with the original Green Revolution strategy. Not only did pesticides kill fish, but some modern high-yielding rice varieties mature too early to allow fish to grow to market size. With the adoption of some new pest-resistant rice varieties, however, fish farming is being renewed in parts of Indonesia, Thai- land and China. With fish yields of up to 500 kg/ha and no apparent decline in rice yield, this is clearly an attractive proposition.
Techniques discussed in the book include breeding plant varieties for resistance, cultural pest control, use of microbial, viral and other predator organisms to attack pests, and botanical pesticides. No single method is promoted as the ultimate solution, as all have their part to play. The authors emphasize that much research remains to be done, in the laboratory as well as in the field where indigenous farmers' knowledge may be tapped. A wholistic approach to IPM, in which it is seen as an integral part of farming systems research carried out with full participation of local farmers, is strongly advocated.
John Herbert
This exceptionally clear, well organized and thorough discussion of plant genetics and its place in agriculture can serve as the introductory text for technical college-level or university-level courses taught in English, or as a valuable reference book for courses in other languages Profusely illustrated with tables, diagrams and photographs, it covers not only plant genetics - with emphasis on bio- technology applications - but the social and environmental context in which plant breeding and bio- engineering must take place.
Chapters' topics range from human population dynamics and nutritional requirements, to farming systems, plant biotechnology, plant biology and biochemistry, the role of energy in cropping systems, soil nutrition, soil microbiology, the history of the Green Revolution, pests and pathogens, pest control and plant genetic engineering. The book stresses the notion that, to obtain a sustainable new Green Revolution, molecular crop improvement techniques must be combined with many of the traditional, organic approaches that are ignored in current high-input, industrial production systems With index and chapter bibliographies.
The environmental problems in Third World cities - already the worst on the planet - are bound to increase as the harsh terms of structural adjustment programs and the worsening imbalances of world trace under me new GATT agreement force more and more peasants and their families off the land. Flocking to urban areas which are ill-prepared to receive them, these migrants face a daunting array of environment-related diseases and injuries, which cause millions of preventable deaths yearly In many squatter settlements, for example, infants are 40 to 50 times more likely to die than in Europe or North America This book analyses urban ecosystems, human health and the problems - chiefly political - that give rise to water, air and noise pollution, toxic waste dumping, poor sanitation and housing, and the general degradation of living conditions in cities. Practical solutions are offered for both the symptoms and the causes. A wide-ranging bibliography and useful index are included.
In this volume on the role of climatic uncertainty in tropical farming in semi-and conditions in Africa, complaints about drought have been discarded in favor of practical proposals for making use of available rainfall resources. This more constructive approach is based on more than 20 years of research station and on-farm evaluation of water fluxes in crops under Sudano-Sahelian conditions Risk diagnosis methods based on ecophysiological indicators are proposed, for adoption on plant, plot, catchment or regional scales The papers included in the book, including numerous contributions from CIRAD and ORSTOM staff, were presented at an international seminar in Bamako, Mali, in December 1991, and analyse the stages in the water cycle, explaining the interactions between water management and the tech meal itineraries practised in the tropical ecosystem Illustrated with extensive tables, diagrams and chapter bibliographies No index.
The interest and support the Farmer First philosophy received has led to considerable change in the agricultural sciences, especially in extension practice. While many hailed this populist perspective as a step in the right direction, some argued that its performance-oriented approach failed to capture the complex cultural, social and political dimensions of knowledge, creation, innovation, transmission and application within both rural society and scientific organizations.
This new book goes beyond the limitations of Farmer First by taking a process approach to agricultural research and extension - a process in which choices are made, alliances formed, exclusions effected and worldviews imposed. It describes agricultural development as an essentially ideological and political process, and indicates that a radical re-thinking of the interplay between knowledge, power and agricultural science is under way. With index and extensive bibliography
NEGLECTED HARVEST
"Declaring a locally useful species a weed is another aspect of the politics of disappearance, by which the space of local knowledge shrinks out of existence."
- Vandana Shiva
LUPIN (Lupinus spp.)
Probably of Asian origin, the lupin was cultivated in ancient times as a food crop. The seed is particularly rich in protein (more than 50 per cent) and carbohydrates; it is only edible after it has been cooked in boiling water to eliminate the bitter taste and alkalis.
The lupin grows wild on many terrains, from uncultivated arid areas to clearings in scrub-land (often in acidic soils). It was cultivated by the ancient Egyptians and was very important in Roman and medieval times.
Some species used as food crops come from the American continent and grow at high altitudes in the Andes, such as tarwi (Lupinus mutabilis). American species on the northern Pacific coast have given us perennial ornamental varieties with white, yellow, purple or blue flowers. The wild lupin found in the state of New York (Lupinus perennis) supports a small population of an endangered species of butterfly, the Lycaeides melissa samuelis.
Lycaeides lives in a sandy habitat called the Pine Barrens, an area of dunes where oak and pine trees grow only to be razed periodically by fire. The wild lupin is a "fire plant" which quickly colonizes the broad open clearings left by fire, and the sole source of food for the caterpillars of Lycaeides.
This small butterfly is what ecologists call a "fugitive species," that is, one that inhabits an unstable ecological niche and in this case is driven from one place to another because it is dependent on one food source, a plant that colonizes and slowly takes over different sites.
Not long ago the Pine Barrens covered at least 10 000 hectares and so was able to sustain the population of butterflies. But urban development has reduced the area to less than 1 000 hectares, which is no longer enough to ensure the butterfly's survival.
Research and art work by Marisa Ceccarelli
Apicultura practica en America Latina,
by Luis Guillermo Cornejo
The latest (No. 105) in a group of manuals for beekeepers published as part of the FAO Agricultural Service Bulletin series, this comprehensive, profusely illustrated book covers everything from the anatomy and biology of the European honeybee (Apis mellifera) and the practical details of feeding and hive construction, to advice on disease control, production and marketing of honey, wax, pollen and other bee products. Credit facilities and legislation concerned with beekeeping are also discussed in detail. Available in Spanish only.
Price: US$17. A 35 per cent discount is available for buyers in developing countries.
Also in the series (available in English):
Tropical and sub-tropical apiculture (No. 68), 1986, US$29.
Honeybee mites and their control (No. 68/2), 1986, US$14.
Honey and beeswax control (No. 68/3), 1986, US$7.
Beekeeping in Asia (No. 68/4), 1986, US$10.
Honeybee diseases and enemies in Asia: a practical guide (no. 68/5), 1987, US$7.
Beekeeping in Africa (No. 68/6), 1990, US$10.
Available from: FAO Distribution and Sales Unit, Viale delle Terme di Caracalla, 00100 Rome, Italy.
P/V6640E/1/7.95/12,000
