Genetic analysis for various agromorphological and quality traits in bread wheat (Triticum aestivum)

Abstract

A study was made to estimate gene action and combining ability effects involving 10 diverse parents and their 45 F1s (half diallel approach) developed and evaluated during 2012-13 and 2013-14 crop seasons, respectively. The general combining ability (GCA) estimates for bread wheat (Triticum aestivum L.) genotypes namely, HD 2967 (days to maturity, plant height); DBW 90 (plant height, spikelets/spike, grains/spike, grain yield); HD 2824 (plant height, spikelets/spike); HD 3095 (spikelets/spike, grains/spike, grain yield); and HD 2733 (plant height, days to maturity and grains/spike) showed favourable GCA effects. Estimates of specific combining ability (SCA) effects revealed that cross combinations DBW 90 × HD 2733, HD 3095 × RAJ 4246, PBW 435 × HD 2824, PBW 435 × RAJ 4246 and HD 2967 × RAJ 4246 showed high and significant SCA effects, and thus might be exploited through heterosis breeding to improve these traits. Significant values of additive (D) and dominance (H1) variance for six traits (plantheight, grains/spike, spikelets/spike, 1000-grain weight, gluten content and grain yield) indicated that expression of these traits is controlled by both additive and non-additive type of gene action. Positive and significant values of h2 for plant height, grains/spike, spikelets/spike, 1000-grain weight and grain yield; indicated preponderance of dominance component. Average degree of dominance (H1/D)1/2 was more than unity in most of the F15 for grains/spike, spikelets/spike, 1000-grain weight, gluten content and grain yield, thereby indicating the preponderance of over-dominance gene action. Positive and significant values of F-test indicated the preponderance of dominance and positive genesin the expression of these traits. The proportionate distribution of dominant and recessive alleles indicated presence of dominant alleles in the parents. Regression analysis indicated that days to maturity, plant height, grains/spike, 1000-grain weight, gluten content and grain yield were governed by dominance gene action. Genotype HD 3095 contained maximum dominant genes for days to maturity, spikelets/spike; while HD 2967 for plant height, grains/spike, 1000-grain weight and HD 2824 for gluten content and grain yield that thus these could be utilized as donorsfor bi-parental mating or diallel selective mating system for improvement in these traits.

Genetic Variability and Direct Selection Parameters in Wheat (Triticum aestivum L. M. Thell.)

“…A perusal of Table 2 showed high estimates of heritability for tillers per plant (44.74), harvest index (34.45), grain yield per plant (31.51) and 1000-grain weight (30.54). Above results are in close agreement with the findings of Maurya et al [15]; Meena et al [16] and Mecha et al [17].…”

“…Analysis of variance for the design showed the significant difference between the genotypes for the characters such plant height (45.94), tillers per plant (1.34), 1000-grain weight (3.48), biological yield per plant (31.14), harvest index (13.96) and grain yield per plant (3.58). Similar findings have also been reported by Rangare et al [13]; Maan and Yadav 2010; Zine et al 2013; Verma et al [8], Yadav et al [14], Maurya et al [15]; Meena et al [16] and Mecha et al [17].…”

“…The maximum values of phenotypic coefficient of variance were recorded for tillers per plant (13.37), followed by grain yield per plant (8.29), grains per spike (7.80), harvest index (6.72), plant height (5.89), spike length (5.42), peduncle length (5.30), flag leaf area (5.21), days to maturity (5.19), chlorophyll content (5.14) and 1000-grain weight (3.71),. Similar findings for these traits were also recorded by Yousaf et al 2008; Rangare et al [13]; Meena et al [16]; Govind et al [18] and Mecha et al [17].…”

Assessment of gene action for morpho-physiological and biochemical trait in bread wheat (Triticum aestivum L.)

“…These findings suggested that the additive gene effect plays a major role in quantitative expression of these traits. Similar findings were reported by Ljubicic et al, 2016 for number of grains per spike, Usman et al, 2013 andKumar et al, 2013 for spike length. For the improvement of these traits selection would be effective in early segregating generations.…”

Water Saving and Increasing Water Productivity Using New Planting Methods for Wheat Crop

“…Many benefits from bed planting have been reported by Kumar et al (2007) and Holland et al (2007). Likewise, there are some benefits of this planting system such as low seed rate, reduction of crop lodging, better control of excess water in heavy soil conditions (Sayre and Ramos 1997).…”