National Academy of Agricultural Sciences (NAAS)
|
PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
Biometric analysis was taken up to assess the combining ability of set of Bt cotton parents to harness high yield under contrasting planting densities through heterosis breeding. Twenty test crosses were generated out of Line (5) X Tester (4) mating design involving selected parents with diverse plant architecture. Field experimentation with randomized complete block design (RCBD) with three replicates was adopted to generate the quantitative data on maturity, plant architecture, yield components and key fibre quality traits under conventional density planting (CDP) and high density planting (HDP). The pooled analysis of variance for combining ability revealed significant line x tester interaction effect for all the traits under both planting densities whereas standalone line and tester effects displayed varying effects for array of traits. Proportion of gca/sca variance found to be higher for traits such as days to 50% flowering, days to first boll opening, number of monopodial branches, ginning out turn, seed index, 2.5% span length, bundle strength and micronaire value indicating the preponderance of additive gene action. On contrary, for traits such as plant height, number of sympodial branches, boll weight, number of bolls per plant, seed cotton yield per plant recorded fractional values, indicating the prevalence of non-additive gene action. This phenomenon intern warrants for heterosis breeding as choice of method for genetic improvement of corresponding traits. Line SC1134 and tester SC1205 found to be good general combiner for the majority of the traits with broader utility, which could be explored as potential parents to breed for versatile hybrids for contrasting plant densities. And also identified, test cross combinations SC1104 X 1205 and SC1134 X SC1133 with high magnitude of sca effects under CDP and HDP respectively. These combinations can be considered as potential F1 hybrid crosses to achive high yield potential through heterosis breeding.
Citations |
 |
 |
 |
 |
