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Books and Book Chapters: Recent submissions
Now showing items 201-220 of 977
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Soybean
(1997) -
Subsistence agriculture in Central and Eastern Europe; how to break the vicious circle?: studies on the agricultural and food sector in Central and Eastern Europe
(2004)Subsistence agriculture is probably the least understood and the most neglected type of agriculture. In a globalised, market-driven world, it remains at the same time a myth and a marginal phenomenon. CONTENTS: Subsistence Agriculture in Development: Its Role in Processes of Structural Change; Franz Heidhues, Michael Brüntrup. Institutions and Technologies for Subsistence Agriculture: How to Increase Commercialization; Zvi Lerman. Policy Options to Overcome Subsistence Agriculture in the CEECs; ... -
Farmer seed systems for pigeonpea in coastal Andhra Pradesh
(2004)Seed is one of the main inputs in all cropping systems. Farmers take utmost care in seed selection as poor quality seed material can result in poor harvests and even crop loss. Seed systems can be classified as farmer and formal seed systems. In the target areas in north coastal Andhra Pradesh, pigeonpea is grown as a subsistence crop and farmer seed systems predominate. Both farmer and formal seed systems operate in the Telangana region where crops are grown with a market orientation. The farmers ... -
Relief seed assistance in Zimbabwe
(2004)Zimbabwe has been a recipient of food or seed aid since the 1990/91 drought, considered one of the worst in 100 years. At present, as in the past, interventions aimed at agricultural rehabilitation and recovery have focused on direct seed distribution ("seeds and tools"). While these interventions are being modified to better address the needs of farmers recovering from disaster, they are still based upon the premise that the emergency has resulted in a loss of seed and other assets, and there is ... -
The ability to fix N is not the only key to delivery of the benefits of BNF to farmers: experience of IITA in the savannas of Africa
(2004)The IITA in its research for sustainable soil fertility management has passed through several stages during which legume-based systems were always at the forefront. Alley cropping has N yields of more than 200 kg ha-1 with 50% N2 fixation. In the case of Mucuna cover cropping, the ecological benefit was unequivocal, with more than 100 kg ha' of N2 fixed and consistently positive effects on crop yields. But adoption by farmers has been too low to bring the benefit of BNF to farm households. Based ... -
Relief seed assistance in Ethiopia
(2004)For more than 30 years, the international community has been assisting Ethiopia in recovering from recurring disasters. A continual need for emergency agricultural assistance as a response to droughts, conflict snd famine has led many to question the effectiveness and sustainability of the current interventions and to search for alternative approaches. This paper discribes the approaches used for agricultural recovery in Ethopia, including problem diagnosis, design and implementation of interventions ... -
Vertical rootpulling resistance in maize is related to nitrogen uptake and yield
(2004)Poor soil fertility and recurrent drought are major constriants to maize production in the West Africa savanna. The development of maize cultivars with superior rooting system to absorb nitrogen and water efficiently from the soil is desirable. However, direct measurement of root characteristics for rapid selection of maize lines having tolerance to the two stresses is difficult. Vertical root-pulling strenght, which has been shown to relate well to the rooting charactristics of the maize plant ... -
ICRISAT genebank
(2004) -
Tissue culture in disease elimination and micropropagation
(1992)Meristem-tip culture is commonly used to eliminate viruses from plants. The fact that some viruses are more difficult to eliminate than others has led to the use of thermotherapy and chemotheraphy, along with meristem-tip culture, to increase the efficacy of disease elimination. Tissue culture material is considered to be the most suitable form to international exchange of vegetative plant material and is accepted by quarantine authorities. Micropropagation is used in both research institutions ... -
Tissue culture of root and tuber crops at IITA
(1992)At IITA, tissue culture methods, such as meristem, shoot-tip, and node-cutting cultures, are used routinely to eliminate virus infection from improved clones of cassava and yam and for micropropagating cassava, yam, sweet potato, and cocoyams. Virus-tested improved clones of cassava, yam, and sweet potato have been distributed to national programmes for evaluation and testing. The clonal germplasm is conserved by the in vitro reduced growth storage method; plantlets can be kept in the same tube ... -
Cytogenetics and crop improvement
(1992)In many crop species, the transfer of agronomically important genes from wild species has been possible through chromosomal manipulations. Haploids have been useful in the production of homozygous lines. Induced polyploids find direct use in crops in which the seed is not the economic produce. As illustrated by triticale and wheat, the development of amphiploids and addition and substitution lines are important in crop improvement. Meiotic modifications resulting in 2n gametes appear to be useful ... -
Constraints in the accessibility and use of germplasmcollections
(1992)This paper discusses the problems associated with the lack of precise techniques for measuring the diversity of a crop species, selecting materials for accession, and determining the appropriate size for a core collection, as well as the boundaries of a genepool. The authors list the most important constraints to accessibility and use of germplasm collections, and indicate areas where biotechnology techniques can offer help. Among the research areas considered important for better utilization of ...