Indian Journal of Genetics and Plant Breeding (The)
Year : 1981, Volume : 41, Issue : 1
First page : ( 88) Last page : ( 96)
Print ISSN : 0019-5200. Online ISSN : 0975-6906.

Single and three-way crosses for generating composite populations in rapeseed

Katiyar R. K., Arunaghalam V.¹

Division of Genetics, Indian Agricultural Research Institute, New Delhi-llO 012, India

Present address: ¹lARI Regional Station, Rajendranagar, Hyderabad-500 030 (India).

Summary

Two unconventional systems of mating using inter- and intra-line variability generated by disruptive and directional selection were examined in Brassica campestris var. brown sarson in the context of breeding high yielding composite populations. Single crosses obtained by mating lines derived from disruptive with those from directional selection, and three-way crosses, using intra-line hybrids of disruptive selection as females with elite varieties as males, provided potential initial gene pools for generating composites, some of which were superior to checks and are being tested at national level. Parents were classified as high (H) and low (L) general combiners over a number of yield components. H × L and self-incompatible × self-compatible single crosses provided high frequency of heterotic crosses. Besides genetic divergence, compatibility divergence added another dimension for realising heterosis. Heterotic crosses with high specific combining ability were identified to be useful to constitute initial gene pools foi generating productive composite populations.

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