F2 derived lines (160) in F4 from four macrospenna x microspenna crosses, selected on
the basis of high seed yield/plant (g), and high harvest index in the background of
bold seed size from 713 F2· derived lines in F3 were evaluated in an augmented
randomized block design under two nitrogenous regimes Le., 20 kg N/ha (E-!) and
40 kg N/ha (E-ll). Estimates of correlation coefficients of selected F2 derived lines in
F3 with the corresponding lines in F4 were highly significant and positive with respect
to seed yield/plant (0.91 and 0.92 in E-! and E-ll, respectively), biological yield/plant
(0.75 and 0.72 in E-! and E-ll, respectively) and 1OO-seed weight (0.91 and 0.92 in E-!
and E-ll, respectively). At 5% selection intensity, standardized selection differential was
observed to be the highest for all studied traits followed by 10% and 22.5% selection
intensities. Standardized response to selection at 5% selection intensity was estimated
to be the highest for all traits in E-ll and it was equally good in E-! also. However,
E-ll was observed to be superior for all the traits for estimation of response to selection
at different selection intensities. The realized heritability of seed yield/planl was
estimated to be high at 5%, 10% and 15% selection intensities in E-ll. For 100- seed
weight the estimated realized heritability was high in all cases. The present results
favour the view that most desirable gene combinations can be identified even in the
heterozygotes. On the basis of present results yield test in F3 is advocated.
Keywords: Macrosperma x microsperma derived gene pool, standardized selection differential, standardized response to selection, early generation testing, realized heritability.
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
OM VIR AND V. P. GUPTA info_circle