Genetic coefficients and agroecolgical potential of dual purpose soybean varieties for up scaling in Kenya
| dc.contributor.author | Nyambane, Nyang'au Alfred | |
| dc.date.accessioned | 2011-08-18T13:28:17Z | |
| dc.date.available | 2011-08-18T13:28:17Z | |
| dc.date.issued | 2011-08-18 | |
| dc.description | Department of Environmental Studies and Community Development, 106p. The SB 205 .S7N9 2009 | |
| dc.description.abstract | Soybean (Glycine max) is one of the popular pulses in the world. Despite its importance as a source of edible oils, cheap proteins and vitamins, as well as its contribution in the animal feed industry, its cultivation by farmers in Kenya is below the demand, which is however fulfilled through imports. Soybean production fluctuates in response to agro-environmental conditions. It is in this light that it is important to understand the reasons behind the lack of uptake of soybean in Kenya and identify measures that are required to reverse this trend. Although reasons for lack of uptake are likely more of socio-economics or infrastructural than of a biophysical nature, virtually no agronomic studies have been carried out with dual purpose soybean varieties to evaluate whether they retain their dual purpose nature under Kenyan conditions. This study therefore aimed at determining the genetic coefficients of these dual purpose soybean varieties using Inverse Modeling Method. These coefficients representing various varieties were then used in the simulation of selected agro-ecological zones to gauge their performance. The simulation of their growth and productivity under different environments in Kenya was done using CROPGRO model, a component of Decision Support System for Agrotechnology Transfer (DSSAT) model. Areas in Kenya with highest potential for cultivation of particular varieties were identified, hence shedding light on the uptake bottlenecks at the biophysical level and consequently aiding in identification of agro-ecological zones where these varieties can do best. The high potential areas were found to be the most productive for soybean varieties. The dual purpose varieties studied were the TGX varieties developed in West Africa whose names were coded to SB for simplification. SB 8, SB 3 and SB 20 were the most stable across sites. However, the early maturing varieties such as SB 9 and SB 19 also did well in areas with a short growing season compared to the local variety- SB 23 (Nyala). Differences among varieties for phenological coefficients were rather small, with the Coefficient of Variation (CV) among varieties for individual characters ranging from 4.19 to15.24%. Varieties should be selected appropriately depending on the length of the growing period or can be grown back to back to take advantage of the short rains in order to maximize production. The results clearly demonstrate that CROPGRO model simulated phenology and yields quite well for most of the varieties across contrasting sites | en_US |
| dc.description.sponsorship | Kenyatta University | en_US |
| dc.identifier.uri | http://ir-library.ku.ac.ke/handle/123456789/971 | |
| dc.language.iso | en | en_US |
| dc.subject | Soybean --Kenya | |
| dc.title | Genetic coefficients and agroecolgical potential of dual purpose soybean varieties for up scaling in Kenya | en_US |
| dc.type | Thesis | en_US |