Genetic Analysis of Yield Components and Quality Traits in Rice (Oryza Sativa L.)

Abstract

The present investigation on "Genetic analysis of yield components and quality traits in rice (Oryza sativa L.)" was undertaken to assess the information on genetic parameters for grain yield and quality traits. The experimental material was comprised of twelve diverse parents and their 66 f, .• excluding reciprocals of a diallel cross. All the genotypes were evaluated in a Randomized Complete Block Design with three replications at Crop Research Center of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, during lcharif 2011 and 2012. The observations recorded on eighteen traits viz., days to 50% flowering, days to maturity, plant height. number of productive tillers per plant, panicle length, number of branches per panicle, number of grains per panicle, biological yield per plant, grain yield per plant, harvest index, l 000-grain yield, hulling %, kernel length, kernel breadth, UB ratio, kernel elongation after cooking, kernel elongation ratio and amylose content were subjected to the statisticallbiometrical analyses. The analysis of variance revealed significant differences among the genotypes for aU the traits justifying the presence of adequate variability. The variance between parents, crosses were also highly significant in respect of most of all lhe traits except number of branches per panicle is positive and non-significant in the case. The variance between parents vs crosses were also highly significant in respect of most of all the traits except kemel length and UB ratio are positive and non-significant. The variance component analysis indicated that bolh additive and dominance types of gene actions were involved in almost all the ltaits with higher magnitude of dominance component than additive component for all the traits. Since the degree of dominance, was greater than unity for the truit~ viz .. days to SO% flowering, number of productive ti llers per plant, number of brunches per panicle, biological yield per plant, grain yield per plant, harvest index, kernel length, kernel breadth, I.JB ratio, kernel elongation a&r cookmg and kernel elongation ratio exhibiting over dominance. The average degree of dominance (H1/ 0)1~ 11as less than unity for the traits viz .. days to maturity, plant he•ght, panicle length, number of grains per panicle, 1000-grain weight, hulling and amylose content, indicating thot these traits are governed by partial dominance. Highly significant variances were noticed for both general and specific combining ability for all the characters. The parents viz. CSR-13 and CSR-30 were identified as good general combiner for grain yield and quality traits. Fifteen crosses 1•i:., CSR-10 x CSR-30, Pusa-2511 x CSR- 30, MAUB-57 x Pusa-1401, Pusa-25ll x CSR-13, MAUB-13 x Basmati-370, CSR-10 x Pusa Basmati-!, MAUB-57 x CSR-13, Vallabh Basmati-21 x Pusa-1401, Vallabh Bnsmati-21 x Vallabh Basmati-22, Basmati-370 x Pusa-1401, Pusa-2511 x Vallabh Basmati-22, MAUB-13 x CSR-30, MAUB-13 :< MAUB-57, Vallabh Basmati-22 :< Basmoti-370 and Pusa-1121 x MAUB-57 exhibited highly significant and positive sea effects for grain yield per plant, involved otleast one parent exhibiting significant gca eOects and could be placed in high x low category. Five cross combinations vi::., CSR-10 x Pusa Basmati- I. Vallobh Basmati-21 x Pusa Basmati-!, CSR-30 x MAUB-57, CSR-10 x CSR-13 and CSR-30 x CSR-13 showed positive and significant sea efTect.s for amylose content. Fourteen crosses vi: .. I\IIAUB-57 x Puso-1401, CSR-10 x CSR-30, Pusa-2511 x CSR-30, MAUB-13 x Basmati-370, CSR-10 x Basmati-370. CSR-10 x MAUB-57, Basmati-370 x Pusa-1401, Basmati-370 x MAUB-57, Pusa-1121 x MAUB-57. Vallabh Basmoti-22 x Basmati-370. CSR-10 x Pusa Basmati-I, Vallabh Basmati-22 x Puso-1401. MAUB-13 x J'v!AUB-57 and MAUB-13 x CSR-30 displayed positive and highly significant heterosis for groin yield per plant and quolity contributing traits. High phenotypic and genotypic coefficient of variotion was ob:;cfled for groin ) ield per plant foll011ed b) h&r\est index. number of producti1e tillers per plant, number of croins per panicle. plant height. biological yield per plant, UB ratio, Lc:rnel elongation after cooking. and kernel length. The high heritability revealed with genetic advance were observed for number of grains per plant, plant height and biological yield per plant. Grain yield per plant was highly significant and positively associated with harvest index, number of grains per panicle, hulling, biological yield per plant, number of branches per panicle, number of productive tillers per plant, kernel breadth and panicle length. In the path coefficient analysis, kernel elongation after cooking displayed high order of direct effect on grain yield per plant followed by harvest index, biological yield per plant, kernel breadth, number of branches per panicle, plant height, days to so~. nowering and UB ratio. This study revealed the importance of both additive and non-additive gene action in the improvement of grain yield and its component characters studied. As both additive and non-additive gene actions 111e important, further improvement of grain )ield and its components characters in the material is not possible by simple pure line selection or modified pedigree selection. Hence, improvement can be expected by delaying the selection to later generations, when dominance and epistatic interactions disappear and resorting to intennating of segregants followed by recurrent selection. From the foregoing study. it can also be concluded that emphasis rna) be gi\en to the characters like plant height, number of productive tillers per plant, panicle length. number of branches per panicle, number of grains per panicle, biological yield per plant and harvest index, while selecting the genotypes. Selection pressure may also be more towards the rraits like hulling %, kernel length, kernel breadth, UB ratio, kernel elongation after cooking. kernel elongation ratio and amylose content for the genetic improvement in grain quality of rice.