Direct and Indirect Selection Parameters in Bread Wheat (Triticum aestivum L.)

A study was conducted at Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut (U. P.), during rabi 2010–2011. Correlation coefficient and path analysis were performed for yield and its contributing characters in 49 wheat genotypes. The correlation coefficients of grain yield per plant, days to 50% flowering, and days to maturity were non-significant. Gluten content showed highly significant and negative correlation only with productive tillers per plant (−0.256) and with remaining characters were non-significant. The grain yield per plant exhibited highly significant and positive correlation with biological yield per plant, test weight, productive tillers per plant, and number of grains per spike, number of spikelets per spike, spike length with awn, plant height, and significant and positive correlation with harvest-index. It is suggested that these characters can be considered as selection criteria in improving the grain yield. The highest positive direct effect on grain yield per plant was exerted by biological yield per plant (0.6249), followed by productive tillers per plant (0.2215). In contrast, days to maturity (−0.0085) and gluten content (−0.0047%) contributed considerable negative direct effect on grain yield per plant. The very low value of direct effects recorded in case of remaining nine characters indicated that their direct contribution to grain yield was too low to be considered of any consequence. 1000-grain weight (0.4117), productive tillers per plant (0.3412), number of grain per spike (0.2714), number of spikelets per spike (0.2316), ear length with awn (0.1994), and plant height (0.1736) were exerted substantial positive indirect effects on grain yield per plant via biological yield per plant.