Pumpkins (Cucurbita spp.) are an important specialty vegetable. Field studies were conducted on three pumpkin cultivars characterized with different growth habits to determine the effects of plant population and genotypes on marketable yield. Increasing plant populations from 4780 to 9560 plant per hectare resulted in significantly greater fruit number and yield in both growing seasons and for all tested genotypes. Average fruit weight declined at the higher populations. The response of pumpkin genotypes to different planting densities was genotype (growth habit) dependent since the response was pronounced in large vine types compared to bush type. The phenotypic variation existed among pumpkin genotypes for yield seems to be under genetic control. Foliar application of potassium improved growth and yield of pumpkin plants although the non-significant effect. These results demonstrate that growers may increase pumpkin yield by increasing plant populations.
KeywordsCucurbita PepoCucurbita MoschataPumpkinPlanting DensityPlant PopulationCompetitionPotassiumCultivar by Environment Interaction
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