Abstract

                                The value of heterosis is known since ancient times to animal breeders. Considerable interest has been generated during recent years in the exploitation of hybrid vigour in crop improvement. The utilization of heterosis appears to be quick, cheap and easy method of increasing yield in vegetatively propagated crops and in cross-fertilized crops like maize, pearlmillet, sorghum, onion etc. But little use has been made of heterosis breeding in self-fertilized crops. The development of genetic and chemical methods of emasculation (Pal and Sikka, 1956) has brought economic production of hybrid seed in self-fertilized crops into the realm of probabi- lity. Recent studies in barley (Jain and Allard, 1960), in Mungbean (Bhatnagar and Singh, 1964) have suggested that heterozygote advantage might be met with in self-fertilized crops also. While studying a large number of economic crosses it was considered desirable to investigate whether any heterosis could be exhibited by crosses among different pure lines of wheat.

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