Sowing date, plant density, fruits per plant and harvest time influenced yield and quality of hybrid seed of bitter gourd ( Momordica charantia ).

摘要

Seed yield of bitter gourd (Momordica charantia L.) is influenced by many factors. This study was conducted to explain hybrid seed yield variation induced by either environmental conditions or cultivation practices. The parental seeds were sown five times with a 15-days interval from February 22 to April 22; plant spacing was 100x30 cm, 100x40 cm and 100x50 cm; fruits per plant were kept as 3-fruit, 6-fruit and no limited. Plant density was the controlling factor of seed yield; higher plant density produced remarkably higher seed yield than those with low density. Sowing date had significant effects on seed yield, the highest seed yield (551.42 g plot-1) was obtained when seeds were sown on March 23, which was 155.44% higher than the lowest seed yield produced by sowing on April 22 (215.87 g plot-1). Seed yield per plot were closely correlated to fruit yield per plot (r=0.9428) and plant number per plot (r=0.6072). Although no variation on germination percentage among seeds harvested in different harvest phase were observed, the 1-15 d harvested seeds shown significantly greater in 1000-seed weight than those harvested in the 16-45 d period of the harvest phase. These results suggest the optimum sowing date (late February to late March), plant density (30,000-35,000 plants ha-1) and fruit set per plant (3 fruits) for seed production of bitter gourd in spring season. Moreover, seed harvest should be scheduled in the early harvest stage to achieve large seed size.