Abstract:

Abstract: In order to provide a theoretical basis and scientific guidance for the water use and yield increase of corn, according to intraspecific competition, the study explored how to increase water use and corn yield in the ridges mulched with plastic film for rainwater-harvesting. There were two types of plastic film mulching on ridge for rainwater-harvesting, which had the same furrow of 60 cm, and their ridge widths were 30 cm and 60 cm, respectively. The two planting density of high and low were used for this plastic film mulching on ridge for rainwater-harvestings. There were three lines corn planted in the furrow in the high planting density and two lines corn in the low planting density. As the control, the bare land also had two planting densities of high and low. The results showed that the rainwater-harvesting had the role of rainwater harvesting and holding soil water. The biomass of single plant and per unit area in the whole growth period, biomass of per unit area at harvest, grain yield and water use efficiency at harvest were significant higher in the ridges mulched with plastic film for rainwater-harvesting than in the bare land. In the ridges mulched with plastic film for rainwater-harvesting of the same ridge width, the high planting density was benefit for the increasing of biomass, grain yield and water use efficiency. After Aug. 15th, due to density effect, the biomass of single plant in the high planting density corn of 60 cm and 30 cm ridge was significant lower than in the middle line than in the edge line, and there was lower harvest index value in the middle line than in the edge line in the 30 cm ridge mulched with plastic film for rainwater-harvesting at harvest, which was the main reason for the lower harvest index and grain yield in the high planting density of 30 cm ridge mulched with plastic film for rainwater-harvesting. There was the highest grain yield in the high planting density of the 60 cm ridge mulched with plastic film for rainwater-harvesting in all treatment. In general, the high planting density and wide ridge for the ridges mulched with plastic film for rainwater-harvesting were the important aspect for the increase of grain yield and water use in the corn of dry land.