DIVERSITY OF SELECTED SORGHUM GENOTYPES USING MORPHOLOGICAL, MOLECULAR AND BIOCHEMICAL MARKERS

Abstract

Sorghum (Sorghum bicolor L. Moench) is a cereal ranked the fifth most vital cereal crop globally following maize, rice, wheat, and barley. It is versatile and is used in numerous culinary and feed products around the world. Sorghum is an economic staple crop and the genetic diversity in its germplasm is an invaluable aid for its improvement. Characterization of the available Kenyan germplasm of sorghum is important in comprehending the dynamics of the genetic material/pool and in improving and sustaining its productivity. The purpose of this study was to assess the genetic diversity among selected sorghum genotypes in Kenya. Thirteen Sorghum genotypes sourced from the University of Eldoret/Rongo university and three checks from Kenya seed Company were analysed using morphological traits, biochemical profiles and ISSR DNA Markers. The field experiments were conducted at Endebess (35°28'10" E longitude and 1°29'17" N latitude) and Sigor (34°51'24" E longitude and 1°4'26" N latitude), replicated three times and arranged in Randomized Complete Block Design. Biochemical and molecular analysis were carried out at the Chemistry and Biotechnoloy Laboratories respectively. Clustering was carried out using UPGMA, AMOVA and PCoA to assess their genetic relationships. PCA revealed that the 3 important PCs contributed 81.78%, 15.33% and 1.5% of the total variation. AMOVA revealed 97% and 3% genetic variation within and among populations respectively. Shannon Weiner Diversity Index (H=2.74) and Shannon-Weiner Evenness Index (J=0.988) revealed a moderate to high level of biochemical diversity and relatively uniform distribution. Genotypes E95A, E1 and T53B were high yielding, early, dual and nutrient dense and could be promoted for commercialization. These findings offer informed precision in selection and improvement for high yield performance drought resistance and nutritious sorghums in the breeding programs in Kenya and Similar Agro-ecologies.