Abstract

                                The term vernalisation is now taken to include all the various adjustments of environmental factors to which seeds and seedlings may be subjected, with a view to hasten flowering and shorten the life cycle of plants. A shortened life-cycle, especially in the case of annual crops, has the advantage of avoiding the hazards of drought, seasonal pests and diseases. There is also the possibility, with such shortened durations, of growing varieties that would normally be incapable of growing in a particular locality. To the plant breeder, reduction of duration by vernalisation can be helpful in speeding up his breeding programme by raising a larger number of generations within a specific period. There are a number of possible pre-treatment processes of seeds and young seedlings that are capable of shortening duration in annual erops, but for large-scale adoption under Indian agricultural conditions, the methods should obviously be such as not to need elaborate equipment. A further limitation is that the method should not shorten the life cycle at the expense of yield but should if possible be such as to improve the yield as well as hasten maturity. This paper describes certain studies made on the effects of vernalizing rice with the aim of shortening duration and improving yields as well.

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