Welcome to the International Institute of Tropical Agriculture Research Repository
Books and Book Chapters: Recent submissions
Now showing items 521-540 of 983
-
Advances in research on cowpea Striga and Alectra
(1997)The parasitic weeds, Alectra vogelii Benth., and Striga gesnerioides (Wild.) Vatke, have become major yield-reducing factors in cowpea. Currently, Striga is more prevalent in the Sudan savanna and Sahelian regions and Alectra in the northern Guinea savanna and southern Sudan savanna regions of West Africa, as well as in East and southern Africa. However, both are fast spreading beyond these limits. Therefore, concerted efforts are being made to develop cowpea varieties resistant to Striga and ... -
Criblage au champ pour la resistance a la cecidomyie africaine du riz: guide de recherche de lIita, No. 34
(1991)La cecidomyie africaine des galles du riz est un insecte ravageur du riz dont la population a recem¬ment connu une veritable explosion dans bon nombre de pays africain s. L'infestation peut provoquer la perte totale de la recolte. Les traitements insecticides pre-sentent de nombreux inconvenients. Le recours aux varietes resistantes reste la meilleure methode de lutte. La resistance est toutefois specifique au site. Un cri-blage realise pendant trois 1I quatre ans sur Ie meme site pennet d'identifier ... -
Relative changes in the nutrient composition of six cultivars of white yam grown in three ecozones of southeastern Nigeria
(1989)The relative changes in the composition of six cultivars of white yam (Dioscorea rotundata Poir) were investigated in three major yam ecozones in southeastern Nigeria. The component parameters measured were crude protein, starch and total soluble sugar of the six cultivars at maturity. Each of the six cultivars was grown in the three locations which represent su bh umid savanna (Zaki-Biam), forest-savanna transition (Abakaliki) and riverine alluvial areas (At ani) for two seasons (1986 and 1987). ... -
Echantillonnage du sol et preparation des echantillons: guide de recherche de Iiita, No. 2
(1991)La method d'echantillonnage du sol choisie des raisons qui motivent l'analyse du sol. Le sol ne forme pas une masse homogene. La vie vegetale, la topographie, les pratiques agronomiques, etc. affectent l'uniformite du sol. L'exactitude des donnees de l'analyse du sol est fonction de la precision avec laquelle les echantillons sont preleves. -
Natural biological control of African rice gall midge in Nigeria: IITA research guide, No. 37
(1991)The African rice gall midge (ARGM), Orseolia oryzivora Harris & Gagne, has recently emerged as an important insect pest of rice in many African countries. Infestation can result in total crop failure. Naturally occurring biological control agents have been identified in Nigeria that can reduce ARGM to tolerable levels. Researchers observed a large percentage of parasitized galls in unsprayed rice fields. Naturally occurring biological control agents attack ARGM population, thus reducing the severity ... -
Principaux insectes nuisibles du mais en Afrique; biologie et methodes de lutte: guide de recherche de lIita, No. 30
(1992)La production du mals, I'une des eerolalea lei plus cultivees dans Ie monde, est serieusement mena-cole par les insectes nuisibles. Lea pertea annuelles ae chiffrent en millions de dollars. Le. molthodes de lutte culturale, chimique et biologique viennent compltlter la rolsistance varietale. La protection ine, alloeiant cea ditTerentes methodes, respecte Ie milieu environ-nant. Seule une approche basee sur la connaissance des degats, de la biologie, de la repartition et du cycle olvolutif des ... -
Shoot tip culture for the propagation, conservation and exchange of Musa germplasm
(1989)This publication reviews in detail the history of shoot-tip culture of Musa, in vitro propagation procedures, in vitro conservation, germplasm exchange using in vitro cultures and potential problems. -
Nutrient effects of modification of shifting cultivation in west Africa
(1989)Recycling of plant residues, fertilizer use and inclusion of trees and perennials in crop fields are key components in systems for improved food crop production on infertile soils in the forest regions of West Africa. 2 On Alfisols of pH 5.5 or higher in the forest and forest-savanna transitional zones, systems including food crop-cover crop rotation, minimum tillage and the judicial use of fertilizer can sustain yields on small farms for 10 years or more without reverting land to bush fallow. ... -
Lutte biologique naturelle contre la cecidomyie africaine du riz au Nigeria: guide de recherche de lIita, No. 37
(1992)La eecidomyie afrieaine des galles du riz (Orseolia oryzivora Hllrris & Gagne) est un insecte ravageur du riz dont la population a recemment eonnu une veritable explosion dans bon nombre de pays Afriellins, L'infestation peut provoquer la perte totale de la reeolte. Plusieurs agents naturels de luUe biologique, susceptibles de ramener !'infestation a des nivellux toIerables, ont ete identifies au Nigeria. Les chercheurs ont observe un important pourcentage de galles parasites dans les rizi/!res ... -
Analysis of the need for biotechnology research on cassava, yam, and plantain
(1992)Cassava, yam, and plantain are staple food crops essential to food security in the humid and Sub-humid tropics of Africa. However, these crops have long growth cycles, high perishability and slow multiplication rates of propagation materials, and they are subject to a number of biological stresses. These stresses include diseases, insects, mites, nematodes, and weeds. There are gaps in our knowledge, especially in the area of genetics, which influence the pace of breeding. Intensification of ...
