Genetic control of tillers/plant, grains/spike, 1000-grain weight, grain weight/spike and
yield/plant in nine generations (Pt, P:z, Fl, F:z, Fs, BCt, BC:z, F2 XP:z, and F2 biparental crosses)
were investigated in an intervarietal cross of breadwheat involving NI 5439 and PH 663,
having higher number of spikelets/spike, grains/spike and grain weight/spike. Biparental
progeny excelled their corresponding F3 and F2 for tiller number, spikelets/spike,
--IP'ains/spike, grain weight/spike,100o-grainweight and yield/plant. Considerable additive
genetic variance was observed for tillers/plant and grain weight/spike while additive and
dominance genetic variance was predominant for 1000-grain weight. The
additive-dominance model was adequate for tillers/plant, grain weight/spike and
yield/plant. Epistatic effects of additive X additive, additive x d.ominance and dominance
x .dominance were observed for 100o-grain weight. The digenic: epistatic model was
inadequate to explain the nature of gene action for spikelets/spike and 1000·grainweight.
Thus, nonallelic interactions should not be ignored in formulating breeding programmes
and the biparental approach would be extremely useful for enhancing genetic variability
and creation of transgressive segregates.
Keywords: Gene action, biparental mating, transgressive segregation, wheat.
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
S. C. MISRA, V. S. RAo, R. N. DIXIT, V. D. SURVE AND V. P. PATIL info_circle