Electronic Journal of Plant Breeding (Mar 2010)
Genetic analysis to assess the physiological efficiency of parental lines in rice (oryza sativa L.)
Abstract
Information on physiological potential of the genotypes is more important in the crop improvement programme, to evolvehybrids suitable for aerobic cultivation. Four CMS lines and 22 male parents were subjected to combining ability analysisand evaluated to identify the best combining parents for developing rice hybrids suitable for aerobic condition. Theinvestigation was carried out under aerobic condition using the line x tester mating design in three replications and studiedfor different biometrical and physiological traits. The aerobic rice culture IR 72875-94-3-3-2 had high per se performancefor grain yield, yield traits followed by higher harvest index, SPAD values, relative water content, total dry matter and rootdry weight. The other genotype IR 71604-4-1-4-7-10-2-1-3 had superior performance for grain yield and for most of theyield contributing traits, relative water content and root length. The hybrids involving IR 72875-94-3-3-2 namely IR 68886Ax IR 72875-94-3-3-2, IR 68888A x IR 72875-94-3-3-2 and COMS 14A x IR 72875-94-3-3-2 had higher grain yield underaerobic condition. Similarly PSBRC 80, the male parent best suited for aerobic condition had better performance for most ofthe traits like harvest index, high relative water content, total dry matter production, root dry weight and grain yield. PSBRC82, the other aerobic culture also had, higher harvest index, leaf chlorophyll content, relative water content and grain yield.The female parents IR 68888A and COMS 14A and the male parents IR55838-B2-2-3-2-3, IR 36, WGL 14 and WGL 32100had good performance for most of the yield contributing traits and physiological parameters under aerobic condition. Thehybrids developed from these parental lines viz., IR 68888A x IR55838-B2-2-3-2-3, IR 68888A x IR 36, IR 68888A x WGL14, IR 68888A x WGL 32100, COMS 14A x IR55838-B2-2-3-2-3, COMS 14A x IR 36, COMS 14A x WGL 14 and COMS14A x WGL 32100 were found superior for most of the yield traits and physiological traits. Therefore, these parental linescould be best utilized for developing high yielding hybrids suitable for water limited conditions.
