PhD fellow, CBBC,Tunisia
Vicia sativa is an important fodder legume, used by farmers as a versatile nitrogen-fixing plant in crop rotations. It is used for green manure as it can either be grazed or cut for hay. Common vetch has small seeds generally 20–90 mg, with a protein content in the range of 240–320 g/kg. However their utilization was hampered by the fact that their seeds contains nitrogenous antinutritional factors, such as cyanogenic glucosides vicianin and prunasin. Cyanogenic glucosides are defense compounds that are hydrolyzed by specific β-glucosidase enzymes as part of a plant defense response. This results in the release of hydrogen cyanide gas. Cyanogenesis is a significant social and economic problem and can limit the use of particular harvests for human or animal consumption. Reducing or eliminating the content of these antinutritional factors can be achieved by a mutagenesis approach or the use of existing natural variation in the species. The project will make a very important contribution to feed security and sustainable agriculture, by improving the protein-rich legume crop Vicia sativa (Common Vetch) as a feed stuff for monogastric animals and as an animal-derived protein for human consumption and consequently for protein rich animal feed crops. Production of low or free toxin varieties of Vicia sativa will encourage farmers to grow it for animal feed as it offers them several economic and environmental benefits.
Abstract: Food insecurity is a chronic problem in Africa and is likely to worsen with climate change and population growth. It is largely due to poor yields of the cereal crops caused by factors including stemborer pests, striga weeds and degraded soils. A platform technology, 'push-pull', based on locally available companion plants, effectively addresses these constraints resulting in substantial grain yield increases. It involves intercropping cereal crops with a forage legume, desmodium, and planting Napier grass as a border crop. Desmodium repels stemborer moths (push), and attracts their natural enemies, while Napier grass attracts them (pull). Desmodium is very effective in suppressing striga weed while improving soil fertility through nitrogen fixation and improved organic matter content. Both companion plants provide high-value animal fodder, facilitating milk production and diversifying farmers' income sources. To extend these benefits to drier areas and ensure long-term sustainability of the technology in view of climate change, drought-tolerant trap and intercrop plants are being identified. Studies show that the locally commercial brachiaria cv mulato (trap crop) and greenleaf desmodium (intercrop) can tolerate long droughts. New on-farm field trials show that using these two companion crops in adapted push-pull technology provides effective control of stemborers and striga weeds, resulting in significant grain yield increases. Effective multi-level partnerships have been established with national agricultural research and extension systems, non-governmental organizations and other stakeholders to enhance dissemination of the technology with a goal of reaching one million farm households in the region by 2020. These will be supported by an efficient desmodium seed production and distribution system in eastern Africa, relevant policies and stakeholder training and capacity development.
Pub.: 19 Feb '14, Pinned: 27 Aug '17
Abstract: Black rice is rich in anthocyanin and is expected to have more healthful dietary potential than white rice. We assessed expression of anthocyanin in black rice cultivars using a newly designed 135 K Oryza sativa microarray. A total of 12,673 genes exhibited greater than 2.0-fold up- or down-regulation in comparisons between three rice cultivars and three seed developmental stages. The 137 transcription factor genes found to be associated with production of anthocyanin pigment were classified into 10 groups. In addition, 17 unknown and hypothetical genes were identified from comparisons between the rice cultivars. Finally, 15 out of the 17 candidate genes were verified by RT-PCR analysis. Among the genes, nine were up-regulated and six exhibited down-regulation. These genes likely play either a regulatory role in anthocyanin biosynthesis or are related to anthocyanin metabolism during flavonoid biosynthesis. While these genes require further validation, the results here underline the potential use of the new microarray and provide valuable insight into anthocyanin pigment production in rice.
Pub.: 03 Feb '11, Pinned: 27 Aug '17