Morphological and molecular markers were employed to study the genetic variability among 40 sorghum landraces collected from Tanzania and two from Zambia. A total of 14 morphological markers and seven simple sequence repeats (SSRs) primers were used to (i) determine the genetic relationships among landraces, and (ii) assess important agronomic traits. Five principal components accounted for 73.60% of the total variability. There were positive significant correlation between yield and inflorescence width (r = 0.343*), five panicles averages and plot yields (r = 0. 531*), leaf senescence and inflorescence length (r = 0.355*). Negative significant correlation between tiller numbers and inflorescence length (r = -0.343*) was recorded. Cluster analysis based on morphological traits revealed three major distinct groups with one landrace forming independent cluster. Based on molecular markers, eleven clusters were observed. Sorghum controls, N13, Ochuti and Adiwo each formed independent clusters. Markers Xgap84 and Xtxp320 had high alleles than other markers. These had seven and eight alleles respectively. Molecular markers clearly separated landraces within and between groups than morphological markers. There were no genotype specific makers with the exceptions of Ochuti and N13 controls.
The resources for agricultural and natural resources research have declined in Zambia. Therefore, there is a need to generate evidence on the rate of return (ROR) on past investments in sorghum research. Zambia's sorghum research programme has released seven widely adapted varieties and management practices. The objective of this study is to assess the socio-economic impact of sorghum research in Zambia from 1983 to 2010 and to assist in identifying priority areas for future research. A multistage sampling procedure was used in the study and a total of 278 farmers comprising 241 small-scale, 25 medium-scale and 12 commercial farmers was interviewed. A surplus approach was used to estimate the ROR to research and development investment. The Akino-Hayami and simple benefit-cost analysis techniques were used to estimate the ROR to investment. The estimated adoption rate in the sorghum producing sector in Zambia was 33.5%. Farmers identified early maturity, drought tolerance and high yield as the most important attributes of improved varieties. About half of the respondents cited a lack of improved seed and information as reasons for non-adoption. The estimated ROR for investment in sorghum research and complementary services ranged from 12% to 19%, depending on the future adoption path.
We applied sequential retrospective (SeqRet) pattern analysis to stratify sorghum variety testing sites according to their similarity for yield discrimination among genotypes using historical grain yield data from 147 multi-environment trials (METs). The trials were conducted at 38 sites in 10 countries of the Southern African Development Community (SADC) region during 1987/1988-1992/1993 and 1999/2000. The analysis for the 6 years 1987/1988-1992/1993, covering 34 sites, clustered these sites into 6 major groups with a model fit of R 2 = 0.75. With additional data from the year 1999/2000, the SeqRet pattern analysis delivered a very similar clustering of the 34 sites, with the additional four sites in 1999/2000 properly classified with appropriate site groups (R 2 = 0.74). The results suggest that future sorghum variety testing could be restricted to a few representative sites selected from within each of the six identified site-groups. #
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.