Abstract

                                The formation and emergence of panicles is a season bound character in some varieties of rice. However, there is some evidence that it is also genetically controlled. Anandan and Krishna. swamy (1934) have recorded the occurrence of earless or Barren-Sterile' type of plants occurring as a segregant in a culture of Muthusamba. They found that one of their cultures was heterozygous and that in a population, the number of plants without panicles was nearly one-fourth of the total representing an approximate 3:1 ratio. In confirmation, they found that some of the apparently normal looking plants segregated similarly in the next generation. Therefore there is a probability of a single mendalian factor being concerned, the heterozygous normal being phenotypically indistinguishable from the homozygous normal plants. This type of inheritance in rice has not been recorded elsewhere and is of extreme interest. Therefore the segregating culture was kept alive at the Paddy Breeding Station, Coimbatore and study continued. The pre- sent paper deals with some new observation made in the course of study.

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