Inheritance of Grain Shattering and Lazy Habit and Their interrelationship In rice*

Shattering habit was found to be governed by two dominant genes in the two crosses H 61 × N 22 and (H 153 × N 22 extract) × 71/R 9. Lazy habit of the plant was found to be controlled by a pair of duplicate recessive genes in the later cross. Linkage between the genes governing lazy habit and shattering behaviour was noted with a cross over value 25⋅4 per cent. The value was however different from the value reported by Nagao and Takahashi (1963). It is concluded that one of the genes for lazy habit and one for shattering nature are situated in the same chromosome in both the sub species—japonica and indica of Oryza sativa; however the relative distance between these is slightly different.