Correlation and Regression Analysis for Yield Traits in Wheat (Triticum aestivum L.) Genotypes

The present research work was carried out at Southern Wheat Research Station, Tandojam during the growing season 2013-14 in order to work out correlation and regression analysis for yield traits in wheat genotypes. The experiment was laid out in a Randomized Complete Block Design with three replications. Eight bread wheat genotypes such as Mehran, Sarsabz, TJ-83, SKD-1, Inqlab, A. Sattar, Sehar and Sassui were used to examine correlation and regression. Seven traits, viz.;plant height, tillers plant-1, spike length, spikelet’s spike-1, grains spike-1, seed index and grain yield plant-1 were studied. The analysis of variance revealed significant differences among the genotypes for plant height, tillers plant-1, spike length, spikelet’s spike-1, grains spike-1, seed index and grain yield plant-1. Based on mean performance, variety Sarsabz gave maximum plant height (95.46), produced maximum tillers plant-1 (4.40), gave more grain spike-1 (63.13), TJ-83 gave highest seed index (47.260), and was next ranker in spike length-1 (12.07), spikelet’s spike-1 (19.13), grains spike-1 (59.86), and grain yield plant-1 (9.86) among the genotypes. The phenotypic correlations revealed that tillers plant-1 and grains spike-1 were highly positively associated;hence these yield components can be used as reliable selection criteria to improve grain yield in wheat. Thus estimation of correlation and regression analysis among yield and yield components may provide effective selection criteria to improve wheat grain yield. The results from correlation and regression of plant height indicated significantly positive association with spikelet’s spike-1, tillers plant-1 and grains spike-1 which revealed that increase in plant height will cause corresponding increase in associated traits.

Heterosis and Combing Ability in F1 Population of Hexaploid Wheat (<i>Triticum Aestivum</i>L.)

The heterosis, heterobeltiosis, general combining ability (GCA) and specific combining ability (SCA) were examined during Rabi (crop season) of 2013-2014 in hexaploid wheat genotypes. The experiment for this study was conducted at the Botanical Garden, Department of Plant Breeding & Genetics, Sindh Agriculture University Tandojam, Pakistan. The breeding material was comprised of four parents (Imdad, TD-1, SKD-1, and Moomal). These parents were crossed in half partial mating fashion;thus, six possible cross combinations (F1s) were obtained (Imdad × TD-1, Imdad × SKD-1, Imdad × Moomal, TD-1 × SKD-1, TD-1 × Moomal, and SKD-1 × Moomal). A three-replicated RCB Design was used. The mean squares corresponding to different traits of various hexaploid wheat genotypes indicated significant (P F1 hybrids) effects for the characters (plant height, tillers plant-1, spike length, spikelets spike-1, seeds spike-1, seed index, and grain yield plant-1). The mean performance of F1 hybrids differed significantly (P < 0.01) for all the traits studied. Among the parents, Imdad and TD-1 proved to be better general combiners for almost all the studied traits. In regards to SCA effects, the F1 hybrids Imdad × TD-1 and Imdad × SKD-1 expressed higher SCA and heterotic effects for most of the studied traits.