关键词: 逐步回归分析, 降水利用率, 小麦产量, 降水年型, 肥料贡献率

Abstract: A field study was conducted to evaluate the effects of intercropping on weed seed germination in sugarcane soil. Four treatments were designed: natural recovery, peanut monoculture, sugarcane monoculture, sugarcane intercropping with peanut. The results showed that the weed seed density and species in the soil of sugarcane intercropping with peanut were reduced by 44.4% and 34.0% compared with peanut monoculture, and by 37.5% and 22.7% compared with sugarcane monoculture, respectively. Compared with soil seed bank before sowing soil and in the natural recovery plots, the dominant species of weed increased but their seed density decreased significantly in the soil of intercropping sugarcane with peanut. The weed yield of intercropping sugarcane with peanut accounted for 33.7%, 40.9% and 55.8% of those in natural recovery, peanut monoculture, and sugarcane monoculture, respectively. Our study suggests that intercropping affects the density and species composition of the weed seedbank by producing higher crop yield and less weed growth through usurping resources from weeds and by suppressing weed growth through allelopathy.

Key words: precipitation pattern, winter wheat yield, fertilizer contribution rate, precipitation use efficiency, stepwise regression analysis