Heterosis and Combining Ability Analysis for Yield and Related-Yield Traits in Hybrid Rice

Abstract

Study of combining ability and heterosis were conducted on 12 F1 hybrids along with seven rice genotypes (three<br />cytoplasmic male sterile lines and four restorer varieties) to know the pattern of inheritance of some<br />morphological traits for selecting superior genotypes. The experiment was carried out according to line x tester<br />mating design, during 2007-08. Analysis of variance revealed significant differences among genotypes, crosses,<br />lines, testers and line x tester interactions for tiller number, plant height, days to 50% flowering, panicle length,<br />number of spikelets per panicle, spikelet fertility and grain yield traits. Variances of SCA were higher than the<br />GCA variances for traits except for plant height which indicated predominance of non-additive gene action in the<br />inheritance of the traits. The highest heterosis (106.60%) was observed in cross IR68899A x Poya followed by<br />other eight crosses for yield and most of its related traits. The proportional contribution of testers was observed<br />to be higher than that of the interactions of line x tester that revealed the higher estimates of GCA variance that is<br />additive gene action among the testers used. Within CMS parents, IR62829A and among male parents, IR50 and<br />Poya were observed to be good general combiners for most of the characters studied. The cross combinations<br />IR62829A x Mosa-tarom, IR68899A x Poya, IR58025A x IR50 and IR58025A x Poya were observed to be good<br />specific cross combinations for grain yield and most of its related traits due to highly significant SCA and<br />heterotic effects

Combining ability analysis for various yield and quality traits in rice (Oryza sativa L.)

“…For rest of the traits studied, female x male component of variances were significant at 0.1% probability level (p = 0.001), indicating that female parents interacted sufficiently with the male parents. These results are in confirmation with the findings of Akter et al (2010), and Bagheri and Jelodar (2010) in rice, who also reported that female parents interacted significantly with the male parents. Combining ability variances in the present study revealed that the magnitude of additive genetic variance (σ 2 A) was higher than dominance genetic variance (σ 2 D) for the characters, days to 50% flowering, days to maturity, plant height, number of effective tillers per plant, 100 grain weight, kernel length before cooking and kernel breadth before cooking, suggesting the preponderance of additive gene action for these traits.…”

“…Significant negative GCA and SCA effects for days to 50 per cent flowering in rice have also reported by Tiwari et al (2011) and Latha et al (2013). Bagheri and Jelodar (2010) observed that IR-58025A exhibited undesirable GCA effect, but most of its crosses revealed desirable SCA effects for days to 50% flowering. The significant negative estimate of GCA effect for days to maturity among the CMS lines was recorded by IR-68897A, whereas amongst the male parents, the highest significant negative value of GCA effect was observed in Pusa Sugandh-3 followed by Pusa Sugnadh-5 and Pusa 2517-2-51-1.…”

“…CMS line IR-68897A was observed to be the good general combiner for grain yield per plant by Thakare et al (2013). Bagheri and Jelodar (2010) observed that IR-58025A exhibits undesirable GCA effect for grain yield, while most of its cross combinations revealed desirable SCA effects for the trait. Salgotra et al (2009) reported that Pusa 2517-2-51-1 was the best general combiner followed by Sanwal Basmati for yield per plant, while Pusa 2517-2-51-1 x Pusa Basmati-1 was observed to be good specific combination for the trait in their study.…”

“…Hybrid, IR-58025A x HUR-JM-59221 exhibited highest significant desirable value of SCA effect followed by Pusa 6A x Pusa Sugandh-5. Bagheri and Jelodar (2010) reported that IR-58025A exhibited undesirable GCA effects as well as undesirable SCA effects in most of its cross combinations for plant height in rice. Salgotra et al (2009) reported Pusa 2517-2-51-1 and Sanwal Basmati as good general combiners, and cross Pusa 2517-2-51-1 x Pusa Basmati-1 as good specific combination for plant height.…”

Combining ability of different yield related characters in Rice

“…Significant mean squares due to lines and tester for a particular trait indicate the prevalence of additive variance. However, significant difference due to interactions of line × tester for some of the characters suggested the importance of both additive and non-additive variance for these traits (Bagheri and Babaeian 2010). Thus both additive and non additive gene actions should be studied for improving yield related traits.…”