The Indian Journal of Genetics and Plant Breeding

Mulberry (Morus sp.) dioecious (male) and monoecious germplasm accessions of different geographical origin showed anthesis period between 1 and 4. Indigenous and exotic accessions of Asian countries flowered during 1 to 2 except few accessions from Japan, China, Burma and Turkey which flowered during 3 and 4 months, while rest flowered during 3 to 4. The number of catkins per axis was more in exotic accessions with small size and less number of florets compared to indigenous one. Dehiscence of anther was highest during 10.00–11.30 AM and 3.00–4.00 PM in the day time, while the event occurred throughout the day and was restricted to 1–4 days (Indigenous 1–3; Exotic 2–4 days) for a single catkin. The size of the pollen showed variation with two germpores irrespective of its origin, except in few cases where the germpores were 3–4. In vitro germination of pollen showed significant variation and did not relate with the origin of the accessions but declined with the increase of storage time.