Pollination Requirements for Watermelon Seed Production

Summary

Watermelon pollination studies in southern Colorado, USA, indicated that insect pollinators were necessary for commercial seed production, and that honeybees were adequate pollinators.

The weight, but not number, of melons, and both number and weight of mature seeds per melon, were significantly higher from plots visited by bees than from those where bees were excluded. Increasing the honeybee populations did not improve melon weight or seed yield.

High correlations were obtained between melon weight and number of mature seeds (0·90) and melon weight and total weight of mature seeds (0·85).

Six species of native bees, as well as the honeybee, seemed to be active pollinators, and Melissodes bimaculata seemed a more efficient pollinator than the honeybee. Present pollinator populations are probably sufficient for commercial seed production in the area. The small fields used in the study, however, may not be comparable to the larger commercial ones, and the cages may have interfered with pollinating activities of the high honeybee populations.