A strategy to identify potential germplasm for improving yield attributes using diversity analysis in sorghum

Abstract

The potential yield levels of sorghum, an important crop in the semi-arid regions of the world, are stagnating due to the narrow genetic base of the genotypes utilized in the sorghum improvement programmes worldwide. For utilization of genetic diversity in any crop, adequate genetic characterization of relevant germplasm is a prerequisite. Therefore, we attempted to identify the potential germplasm lines for improvement of yield in a set of 135 germplasm lines belonging to different races. The experiment was carried out in an augmented design during 2002, and in Randomized complete block design (RCBD) for selected lines during 2003. The correlation studies indicated that besides panicle weight, the number of grains/unit length of primary branch and the number of secondary branches/primary branch had significant positive relation with grain yield. IS nos 1259, 5447, 5725 and 2036 were promising for more than one yield component. The study indicated that besides caudatum race, the lines belonging to guinea, kafir and inter-races with them are good sources for different yield components. Genetic diversity and cluster analysis grouped 40 germplasm lines into eight clusters, with maximum inter-cluster distance between clusters II and III. Utilization of the germplasm lines belonging to different clusters in improving yield components is discussed.