Division of Vegetable Crops and Floriculture, I.A.R.I., New Delhi.
Dry seeds of two varieties of Lathyrus odoratus L. were treated with ethyl methane sulphonate. Changes were observed in flower characteristics in M1 and M2 generations. The frequency of viable mutations was generally low. The mutation spectrum was found to be very restricted to qualitative characters. Cytological abnormalities, like the multivalent association, assymetrical Metaphase I bivalents, association of fragments, and anaphase bridges following meiotic breakage, perhaps as errors of cross over process and abnormal tetrads have been observed in treated plants. Besides, the increase in chiasma frequency, and association of syndrome with meiosis are all associated with such morphological changes in flower form of sweet pea.
