Introduction to major field crops (1+1)

Pollination

Poor seed setting is yet another constraint to limit the productivity of sunflower. The protandrous and self-incompatible nature of sunflower favours cross pollination and is predominantly brought about by insects. The pollination is largely done by honey bees and although other insects like bumble bees also play a role. As sunflower is highly cross pollinated crop, sufficient number or pollinators are necessary for better pollination of all the florets in capitulum to ensure higher seed set and yield. The introduction of bee-hives into the field at an appropriate time can help in seed setting in sunflower. Supplementing the natural pollination with hand pollination results in higher yield.The practice of hand pollination should be done for ten days at anthesis stage early in the morning on alternate days. For this purpose flowers should be rubbed gently with hand covered with soft cloth. This would help pollens to reach all the female flowers and result in higher fertilization.

Fig: Pollination.