Genetic variation and trait relationship in the pearl millet landraces from Rajasthan

Abstract

Landraces of pearl millet (Pennisetum g/aucum) are potential sources of adaptation to stress conditions. Genetic variation among landraces is of vital importance to breeding programmes that aim to produce improved landrace-based cultivars for marginal growing environments. Twenty-eight landraces of pearl millet from Rajasthan were evaluated in two contrasting environments to estimate genetic variation for nine traits including grain yield. Trait association was also studied with correlation analysis. Significant genetic variation was observed for six traits including time to flower, dry stover and total biomass yields. There were no genetic differences for panicles/plant and threshing percentage while differences for grain yield per se were significant at only 10% level of probability. Heritability estimates were low to moderate and ranged from 11 to 52%. Expected genetic advance with 5% selection intensity, expressed as per cent of mean, varied from 2-10%. Correlation analysis showed that grain yield was most strongly associated with biomass yield and stover yield. Plant height, panicle length and threshing percentage were also significantly associated with grain yield. However, individual trait could explain only 22-34% of variation in grain yield. Comparison between landraces and improved cultivars revealed that, in general, the landraces performed better in stress conditions while high yielding modern cultivars were clearly superior in more productive environment. In view of the limited variation for grain yield per se, the genetic diversification of landraces is suggested.