Research of the physiology section was centered on identifying the characters associated with high root yields and quality in cassava under stress conditions. Plant reaction to water stress was studied, specifically regarding growth and yields of var. M Mex 59 and M Col 22 with a period of artificial rain exclusion. Observations were made throughout the stress period and subsequent recovery. Water stress reduced LAI notably although M Mex 59 maintained a LAI approx. twice that of M Col 22 during the stress period. LAI for both var.

Efforts to develop cassava technology for the vast areas of acid infertile soils were continued Large-scale germplasm screening in the field was begun in Carimagua for tolerance to low levels of P and acidity and in Quilichao, for tolerance to low levels of P. Various fertilizer trials were used to determine: (a) nutrient absorption and distribution within the plant during a 12-mo.

Description of geographical aspects of the Subhumid Zone of West Africa and economic and sociological aspects of the Fulani ethnic group, w. emphasis on fodder resources, range management, livestock raising, livestock management, and animal diseases, w. analysis of land use & land development strategies, and directions for future research.

Research review on sheep and goat production in the humid zone of West Africa, w. respect to animal population, production parameters, reproduction, forage production, supplementary feeding based on agro - industrial byproducts, disease incidence, particularly peste petits ruminants & helminthiasis, housing, and economic aspects of small and large scale production, w. proposals for further research.

This audiotutorial unit (cassette, printed script, 76 color slides, study guide, self-evaluation test), prepared by the Communications Support Unit at CIAT, is available for use with a manually or automatically synchronized slide projector/cassette tape reccorder. Each unit is a vailabIe from the Distribution Office at a cost of US$ 50; photocopies of the study guide alone can be obtained from the Cassava Information Center. The objective of this unit is to present some of the results of research conducted by the physiology Section of CIATs Cassava Program.

Se presentan resultados de la investigacion en produccion y utilizacion de pastos y forrajes que indican que en condiciones relativamente buenas de fertilidad natural y de retencion de humedad de los suelos, representadas por la region del litoral ecuatoriano entre Quevedo y Santo Domingo, es posible obtener aumentos de peso diario en novillos de engorde del orden de 450 g/animal y, con cargas de hasta 3 animales, lograr producciones promedio de carne de hasta 1,5 kg/ha/dia, o sea mas de 500 kg/ha/ano, de modo que los animales alcanzan el peso de mercado antes de los 2,5 anos de edad; tambi

Some cultural control measures of weeds in cassava are discussed: quality of the material, planting system and density, density x plant type interaction and use of mulching. In order to study the interaction plant type x planting density, var. M Mex 59 (vigorous) and M Col 22 (nonvigorous) were planted in plots of 7500 and 15,000 plants/ha; and 3 levels of weed control were established: complete, intermediate and no control. The vigorous var.

The animal science systems group at Texas A & M University (TAMU) has developed a computer based beef cattle production model for use in tropical countries. This model can be used to predict animal and herd productivity under a variety of management regions in diverse environments. Economic analyses can then be made, based on these predictions.