单作和间作对玉米和大豆群体辐射利用率及产量的影响

Effect of monoculture and intercropping on radiation use efficiency and yield of maize and soybean

通过两个生长季(2006～2007年)的大田试验,研究了13和23两种间作模式及单作种植对玉米和大豆群体辐射截获与利用以及产量的影响。结果表明,单作玉米、单作大豆、13间作和23间作的消光系数分别为0.45、0.60、0.53和0.52。播后第79d前,间作和单作玉米的干物质量间差异不显著;此后,13间作玉米的干物质量极显著高于单作玉米,13和23间作模式之间玉米干物质量的差异显著;观测期内,大豆干物质量单作和间作间差异显著。玉米/大豆13间作群体的辐射利用率(3.51g·MJ-1)和23间作群体的辐射利用率(3.49g·MJ-1)约为单作大豆辐射利用率(1.24g·MJ-1)的2.8倍,但略低于单作玉米(3.56g·MJ-1)。虽然单作玉米和大豆的籽粒产量均高于间作群体内玉米和大豆的籽粒产量,但间作群体的总产量分别比单作玉米和大豆的产量高约6.0%和320%;间作种植收入比单作玉米高56%～60%,比单作大豆高70%～74%。本研究表明,间作种植能够通过更有效地利用光能来增加作物产量,进而提高农民收入。

Field experiments were conducted to investigate the effect of two intercropping patterns （maize-soybean 1 ： 3 and 2 ： 3） and corresponding monoculture on the capture and use of solar radiation and on yields of maize and soybean in two growing seasons （2006 and 2007）. Results show that light extinction coefficients of monocultured maize and soybean, and 1 ： 3 and 2 ： 3 intercropping are 0.45, 0.60, 0.53 and 0.52 respectively. There is no significant maize biomass difference between the intercropping and monoculture before 79 days after sowing. After the 79-day period, maize biomass in 1 ： 3 intercropping becomes significantly higher than that of maize monocultured at 0.01 probability level. There is a significant difference in maize biomass between 1 ： 3 and 2 ： 3 intercropping at 0.05 probability level. Soybean biomass of intercropping and monoculture is significantly different. RUE value of 1 ： 3 （3.51g·MJ^-1） and 2 ： 3 intereropping （3.49 g·MJ^-1） is about 2.8 times that of monocultured soybean （1.24g·MJ^-1）. However, it is slightly less than that of the monocultured maize （3.56g·MJ^-1）. Grain yields for monoccultured maize and soybean are more than those for intercropping treatments. However, total yields for intercropping treatments are 6.0% and 320% higher than the yields for monocultured maize and soybean respectively. Incomes from the two intercropping systems are 56%- 60% and 70% - 74% higher than those from monocultured maize and soybean. The findings suggest that intercropping may help increase crop production through more efficient utilization of solar radiation, hence increase farmers＇ income.