Optimum planting density and harvest stage for little-leaf and normal-leaf cucumbers for once-over harvest

Abstract

Optimum planting density and harvest stage were determined for once-over harvest of little-leaf and normal-leaf cucumbers. Three harvest stages (10, 25, and 50% oversize fruit) and four plant densities (37,000, 75,000, 150,000, and 300,000 plants/ha) were evaluated on little-leaf cucumber (H-19) and normal-leaf cucumber (Sumter and Regal). Plant density did not affect skin color, seedcell size, and seed size in the cultivars evaluated. However, lighter skin color, larger seedcell, and larger seed size were detected at the later harvest stages in H-19. Harvest stage did not influence fruit skin color in Regal and Sumter, but seedcell size and seed size increased quadratically with harvest stage. H-19 produced the highest yield (tonne/ha) and dollar value ($/ha) followed by Regal and Sumter. Considering fruit quality and dollar value, the 10% harvest stage at 330 000 plants ha−1 was the optimum stage and density for once-over harvest of H-19 under North Carolina growing conditions. Higher yield occurred at the later harvest stages, but poorer fruit quality (increased seed and seedcell size, and a lighter skin color) was associated with those stages. Fruit quality and dollar value of Regal was best at the 10% harvest stage at approximately 240 000 plants ha−1, while 200 000 plants ha−1 was best for Sumter. Key words: Cucumis sativus, cucumber, plant type, spacing, crop ideotype, vegetable production