Material and methodsFor meiotic stduies, young buds were collected between 11.30A. M. and 1.00P. M. and fixed in acetic alcohol (1:3). Anther smears were prepared in propiono-carmine to study the chromosomal associations at metaphase I and distribution of chromosomes at anaphase I. Stainability of pollen grains with propiono-carmine was used as an index for pollen fertility.Degree of self-incompatibility was determined on the basis of percentage seed set under self-pollination.Plants having 0-10 per cent seed set were classified as self-incompatible, those with 11-30 per cent seed set as partially compatible and the others having higher seed set were regarded to be in the self-compatible group. Results Morphology.The polyploid plants, in general, showed a slower rate of growth in the earlier stage but later on exhibited more vigour as compared to the diploids. There was an increase in plant height and stem was thicker. The leaves were broader, dark green in colour and with larger stomata. The flowers were larger and occasionally more than four petals were present (Fig. 1). These plants were late in maturity and continued flowering even when not a single flower was seen in the diploids. Seeds from the tetraploids were significantly bolder as compared to the diploids (Fig. 2) and the seed set was quite normal.An observation of interest was that the polyploids were comparatively more resistant to frost and aphid attack.Cytology. Meiosis in diploids was normal with formation of 10 Its (Fig. 3) and regular separation of 10 chromosomes at anaphase I (Fig. 4). All the tetraploid plants studied had 40 chromosomes showing various types of as

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