Nerson, H., Agricultural Research Organization, Department of Vegetable Crops, Newe Ya'ar Research Center, P.O. Box 1021, Ramat Yishay 30095, Israel

Sixteen cultivars of Cucurbita pepo ssp. pepo, four from each of four fruit-type groups were compared for seed production under field conditions. In another experiment, one cultivar representing each of these groups was grown for seed production at plant densities ranging from 0.5 to 8.0 plants/m 2. There were significant differences in seed yield per fruit among the four fruit-type groups and even larger differences among cultivars within the same group. Cultivars with high seed numbers per fruit tended to have relatively low mean seed weights. Highest fruit and seed yields of three out of the four cultivars were achieved at 4 plants/m2, whereas the highest yield for the fourth cultivar was obtained at the highest plant density (8 plants/m2). The number of fruits per unit area was the most closely related component to seed yield. Percentages of seed germination immediately after seed extraction were similar to those observed after 2 years of storage. © 2005 Elsevier B.V. All rights reserved.