| Abstracts on sustainable agriculture 1992 Gate- GTZ |
|Abstracts on soil fertility|
Publ. of GTZ, 6236 Eschborn, Postf. 5180, Germany, ISBN 3-88085-462-9, 1991, 371 pp., pbk
Increasing crop production and land productivity in the tropics is essential if the food demand of the growing population in these areas is to be met. Of all the soil-related constraints on crop production, low soil fertility is the most severe on more than half of the arable land in the tropics. Infertile soils are acidic and may be deficient in phosphorus, nitrogen and potassium. On these soils crop production can only be improved when fertilizers, in either organic or inorganic form, are applied, and when soil amendments are combined with improved crop production technologies. This is explained by Ewald Sieverding in his book Vesicular-Arbuscular Mycorrhiza Management, in which he describes the role these fungi can play in improving soil fertility.
The author explains that until about 20 years ago, vesicular-arbuscular mycorrhizal (VAM) fungi were virtually ignored by most soil and plant scientists. However, under controlled greenhouse conditions it has been demonstrated that VAM fungi increase phosphorus uptake. They also play a role in the uptake of other plant nutrients as well as in the biological nitrogen fixation of Rhizobium, the biological control of root pathogens, and the drought resistance of plants.
In 1980 a Mycorrhiza Special Project was initiated at the Centro Internacional de Agricultura Tropical (CIAT), in Cali, Colombia. The general objectives of this project were to test the agronomic importance of VAM in tropical crop production systems and to develop practical technologies to utilize VAM fungi as a biological resource to enhance phosphorus uptake and utilization.
Although the content of this book relates directly to South America, with particular reference to cassava, the principles of the VAM technology presented can be transferred to other crops and to conditions in tropical Africa and Asia, provided that the technology is adapted to the prevailing ecological and socio-economic conditions.
1251 92 - 12/77
Germany, study, greenhouse conditions, mycorrhiza, pigeonpea, phosphorus fertilizer, plant growth