Comparative Analysis of Genetic Variability, Water stress Tolerance and Nutritional Properties of Selected Sorghum (Sorghum bicolor (L) Moench) Cultivars in Kenya

Abstract

Water stress is the most common adverse environmental condition that seriously reduces crop productivity. Increasing crop tolerance to water stress may be the most economical approach to improve agricultural productivity and to reduce agricultural use of fresh water resource in arid and semi-arid lands (ASALs). The study was undertaken from 2008 to 2010 to evaluate tissue culture (TC) regenerates of sorghum cultivars with respect to nutritional value and safety, water stress tolerance and to establish the genetic diversity among the sorghum bicolor cultivars. The parent plants were used as controls in the study. The study involved Seredo, El Gardam and Mtama 1 cultivars. Selection of these cultivars was based on tannin content. The genetic variability was investigated using five simple sequence repeats (SSR) markers. Parameters associated with water stress tolerance were measured in the field and in hydroponics experiment and the data were recorded for all the cultivars and subjected to principal component analysis (PCA) and analysis of variance (ANOVA). The nutritional and safety analysis experiment were also done and data recorded and subjected to ANOVA. Simple sequence repeats (SSRs) marker used in the analysis showed a significant amount of polymorphism with an average of 0.675 similarity coefficient. Phylogenetic analysis clustered the 3 cultivars into two main clusters. The TC regenerates compared to their parental controls showed no significant variations (p