A number of wheat varieties which are known to differ in their adaptability have been analysed for chiasma formation and mitotic index under different agronomic and environmental conditions. It has been found that the varieties which are well adapted in respect of yielding ability show, relatively, stability of chiasma frequency and mitotic index under different conditions. They also have a relatively high frequency of chiasmata. The studies indicate the possibility that some cytological parameters can also provide a measure of varietal adaptability.
