Optimal Yield Related Attributes for High Grain Yie ld using Ontogeny Based Sequential Path Analysis in Barnyard Millet ( Echinochloa spp. )

Abstract

Relationship between grain yield and its component traits can improve the efficiency of breeding programs by determining appropriate select ion criteria. An investigation was carried out on barnyard millet ( Echinochloa spp.) global germplasm collection to investigate the association among yield components and their direct and indirect effects on the grain yield of barnyard millet. The experime nt was conducted in 2011 and 2012 in augmented and alpha lattice design, respectively. T he results of correlation coefficients indicated that grain yield had high significant and positive association with flag leaf width and culm thickness during both years, whereas negat ive association of grain yield was observed with basal tillers and peduncle length. Si mple path analysis indicated high direct effects of panicle exertion, flag leaf sheath lengt h, flag leaf width and days to maturity in 2011; and flag leaf width and raceme number in 2012 . However, these high direct estimates were biased due to multicolinearity. Ther efore, ontogeny based sequential path analysis was used to establish the causal relations hips determining grain yield in barnyard millet. Based on the results over the year s, culm thickness and raceme number were found to be important traits for indirect sele ction. The other important traits suggested for inclusion in selection index were inf lorescence length, plant height, flag leaf length, inflorescence width and number of basal til lers per plant. Keywords: Causal relationship, Correlation, Multicolinearity, Predictor variables, Structural Equation Modelling.