Flowering and fruit set of pumpkin cultivars under field conditions

Field experiments with six pumpkin cultivars (Cucurbita pepo L.) were condu cted in Ithaca, N,Y,, in 1992 and 1993 to characterize the patterns of flow ering and fruit set. Plants of all cultivars produced the greatest number o f female flowers and exhibited the highest rate of fruit set 35-45 days aft er transplanting, during the first 2 weeks of greatest flower production (" peak bloom"). During the 3 weeks of peak bloom, each plant produced an aver age of 3.4 pistillate flowers in 1992 and 5.4 in 1993, and fruit set was 50 .9% in 1992 and 74.6% in 1993, yielding 1.7 and 4.0 fruit per plant, respec tively. In 1994, flower production was further studied with the cultivar Wi zard. Flowers were produced in a ratio of 33 staminate to 1 pistillate flow er over the entire season. Climatic conditions appeared to be secondary to physiological factors in affecting flowering and fruit set during all three seasons. Characterization of fruit set patterns in pumpkin may aid produce rs in scheduling pollination services and predicting yields.