Effects of Different Planting Densities on Yield of Mechanical Transplanted Double-cropping Late Rice

Three rice varieties with different growth durations were selected and mechanical transplanted as double-cropping late rice with the two planting densities(14 cm×30 cm and 17 cm×30 cm).The yield and the yield-related traits were measured at mature period to analyze the effects of planting density on the yield of mechanical transplanted double-cropping late rice.The results showed that high planting density was conducive to the yield increase for the cultivar with short growth period,while low planting density was conductive to the yield increase for the cultivar with long growth duration.For the cultivar with a slight shorter growth period,appropriately increasing planting density would make its tank of the yield equivalent to that of the variety with longer growth period,but the seed-set percentage and 1000-grain-weight were higher than those of the cultivar with longer growth duration,so it expressed yield increase in the end.