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Conference Documents: Recent submissions
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Effect of successive cuttings on nodulation and nitrogen fixation of Leucaena leucocephala using 15N dilution and the difference methods
(1990)Despite the widespread use of Leucaena leucocephala in alley cropping systems, little information is available on the effect of different magagement practices on its nitrogen fixation. We studied the effects of three successive cuttings at 12 week intervals on nodulation and nitrogen fixation of L. leucocephala isolines K636 and K28 inoculated with three Rhizobium strains. The 15N isotope dilution and the total N difference methods were used to estimate the proportions and amounts of N2 fixed. ... -
Aspects of plantain breeding at IITA
(1990) -
Breeding for bruchid resistance in cowpea
(1990)One of the most important constraints in cowpea storage is widespread infestation by the seed beetle, Callosobruchus maculatus (F.), commonly known as bruchid. In addition to causing direct seed weight loss, it reduces seed quality and also affects germination. The International Institute of Tropical Agriculture (IITA) initiated a systematic program in 1974 to develop bruchid resistant cowpea varieties and TVu 2027 was identified as moderately resistant. During the last several years, over 8,000 ... -
Availability and use of fodder shrubs and trees in tropical Africa
(1990)Generally, trees occupy a significant niche in the farming systems and overall way of life in tropical Africa. Fodder shrubs and trees (browse) in this region play a significant role both in farming systems, where they are protected as fallow species, and in livestock production. Livestock in this zone depend largely on browse for their dietary protein. Compared with tropical grass, browse is generally richer in protein and minerals. The importance of browse increases with increasing aridity and ... -
The role of weed control in integrated pest management for tropical root and tuber crops
(1990)A discussion is given of control of weeds of root and tuber crops, such as cassava, sweet potatoes, yams and cocoyams [Colocasia esculenta], as part of an integrated pest management programme. -
Plant germplasm collecting missions carried out from Mar 1987 to January 1989 in six African countries
(1990)Collecting missions under the auspices of the IITA to Zimbabwe, Tanzania, Chad, Swaziland, Lesotho and Somalia covered over 24 000 km and collected 2023 accessions of cultivated crops and wild material. Details are given for each of the 6 missions, with information on routes taken, regions visited and accessions collected. The main crops sampled included: cowpeas (Vigna unguiculata), V. subterranea, wild Vigna species, maize and sorghum in Zimbabwe; cowpeas, wild Vigna species, Phaseolus vulgaris, ... -
Estimation of N2 fixation by nitrogenfixing trees in the subhumid tropics using 15N dilution and difference methods
(1991)Nitrogen fixation by leguminous trees contributes nitrogen to agroforestry systems and enables farmers to grow their own nitrogen fertilizer. Estimation of the amount of nitrogen fixed is necessary to asses the value of leguminous trees. In the present paper, the difference method and the 15N isotope dilution method are used to calculate the amounts of nitrogen fixed in the first year by Leucaena leucocephala (with and without inoculation with Rhizobium), Gliricidia sepium and Albizia lebbeck. -
Some aspects of black sigatoka epidemiology in Central America and outlook for future research in Sub-Saharan Africa
(1994)Airborne asco-and conidiospores of Mycosphaerella fijiensis, the causal agent of black sigatoka, were trapped in the Atlantic lowland of Costa Rica, Central America, during two consecutive years. Selected environmental parameters were monitored in a heavily infected plantation of the False Horn cultivar Currare (Musa sp., AAB group). Ascospore release was related to rainfall. Even rainfall of 0.1mm, which was the smallest amount to be registered, resulted in ascospore release. Ascospore dispersal ... -
Plantain breeding at IITA
(1994) -
New challenge confronting social scientists in IARCs with ecoregional mandates
(1994)A meeting was held of social scientists from the International Agriculture Research Centers (IARCs) of the Consultative Group on International Agricultural Research (CGIAR), at the International Service for National Agricultural Research (ISNAR) in the Hague, Netherlands, in August 1992. The meeting was prompted by changes taking place within the CGIAR system towards increased investment in natural resource management research and emerging needs for closer collaboration among the IARCs. The meeting ... -
Recherche participative efficace entre paysans, ONG, SNRA et IITA pour controler Striga hermonthica au Nord du Benin
(1994)This library research report will be particularly useful to French-speaking research workers in agriculture who want to get information about the Participatory Rural Appraisal (PRA). A synthesis is written from several documents and from a questionnaire which has been send to ex-alumni of the French International Course for Development oriented Research in Agriculture (ICRA, Montpellier, France).