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Books and Book Chapters: Recent submissions
Now showing items 221-240 of 983
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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 ... -
Recents developments in cowpea germplasm collection, conservation, evaluation and research at the Genetic Resources Unit
(1990)The history of the Genetic Resources Unit at the International Institute of Tropical Agriculture (IITA) was highlighted. By 1980, the unit engaged in characterization and evaluation of germplasm information. In order to strengthen the units activity and provide a better knowledge of Vigna, the government of Italy funded a project from December 1984 to December 1989. Information on the geographical distribution of Vigna were also given. The unit now maintains 923 accessions of wild vigna species ... -
Agronomy
(1990) -
Cowpea genetic resources
(1990) -
Wide hybridization potential of alien genetic transfers for triticum aestivum improvement
(1990)In the Triticeae, hybridization of alien species with those of Triticum goes back to 1876 when Wilson consciously made the first wide hybrid involving wheat and rye. Rimpau in 1891 obtained seed on a presumably doubled sector in a wheat × rye hybrid and described 12 plants that must represent the first triticale. A more divergent hybrid (wheat × barley) was first reported by Farrer in 1904 that was considered rather improbable to be a true hybrid (Shepherd and Islam 1981). -
Crop protection
(1990) -
Breeding
(1990) -
On-farm research
(1990)
