Flowering, floral biology and pollination in hard and soft flaked types of jack (Artocarpus heterophyllus Lam.)

Abstract

Investigations'on the floral characters of "Varikka' and "Koozha' types of jack (Artocarpus heterophyllus Lam.) were conducted at the Agricultural Research Station, Mannuthy, Trichur on 14 mature trees. There was no significant difference between 'Varikka' and 'Koozha' types in respect of any of the characters studied. The pattern of male and female catkin production was found to differ in jack, the former occurred from October to February while the later was confined to only three months starting from late November to February. In a male catkin, anthesis started by 6 a.m. and continued up to 6 p.m. in a day. This pattern continued for 5 to 7 days in a catkin. Anther dehiscence occurred between 6 p.m. and 7 p.m. on the day of its emergence. The sequence of emergence of stigma on the female catkin was highly erratic and continued for 3 to 4 weeks. Complete fading away of the stigma occurred in 21 to 35 days after anthesis started. The chief agent of pollination was found to be wind although certain amount of insect pollination cannot be ruled out.