间作小麦、蚕豆的产量和竞争力对供水量和化感物质的响应

为了寻求解决间作群体受化感物质抑制作用的理论依据, 本研究通过盆栽试验, 探讨了不同供水水平下(田间持水量的45%、60%和75%), 小麦根系分泌物间甲酚对单作小麦、单作蚕豆、小麦间作蚕豆生物产量、经济产量和两种作物共生期间竞争力的影响。结果表明: 60%和75%供水水平下, 间作小麦生物产量和经济产量较单作显著提高, 45%供水水平下间作小麦经济产量低于单作; 不同供水水平下, 间作蚕豆的生物产量与相应供水水平的单作相比, 增加显著。间甲酚对小麦、蚕豆的产量均具有化感负效应, 间作具有一定弱化间甲酚对蚕豆化感负效应的作用。45%、60%和75%供水水平下, 间甲酚使间作小麦相对于蚕豆的竞争力较无间甲酚处理时分别提高24.82%、19.26%和79.30%; 增加供水可弱化间作小麦的相对竞争力, 无间甲酚和间甲酚处理间作小麦的相对竞争力在75%供水水平下较45%供水水平分别降低158.08%和79.67%。

Yield and competitive response of intercropped wheat and faba-bean to water and allelochemical dose

Academic evidence showing negatively effects of allelochemicals on optimized intercropping systems are largely lacking. To that end, a pot experiment was conducted to study the mechanism of allelopathy in intercropping systems. Three modes of cropping systems (monocropped wheat, monocropped faba-bean and intercropped wheat/faba-bean) were designed with three irrigation rates (45%, 60% and 75% of field capacity). The effects of irrigation rates and 3-methyl-phenol on yields of the different cropping systems were analyzed. Competition between wheat and faba-bean in the wheat/faba-bean intercropping system was also determined. Results indicated that intercropping significantly influenced the biological and economic yields of wheat. Compared with monocropped wheat, yield of intercropped wheat increased under irrigation rates of 60% and 75% filed capacity. However, the reverse was noted in economic yield under irrigation rate of 45% filed capacity. The yield of intercropped faba-bean was significant higher than that of the monocropped faba-bean under different irrigation rates. Allelopathic effects of 3-methyl-phenol on the yield of wheat and faba-bean were negative. Intercropping mitigated the degree of negative allelopathic effect on faba-bean. 3-methyl-phenol significantly enhanced the competitive capacity of wheat over faba-bean in intercropped systems. The competitive capacities of wheat over faba-bean in intercropping system with 3-methyl-phenol were 24.82%, 19.26% and 79.30% higher than those of intercropping systems without 3-methyl-phenol under irrigation rates of 45%, 60% and 75% of field capacity, respectively. On the other hand, increasing irrigation rate weakened the competitive capacity of wheat in intercropping systems. The competitive capacities of wheat over faba-bean in their intercropping systems with and without 3-methyl-phenol under 75% irrigation rates were 158.08% and 79.67% lower than that under 45% irrigation rate, respectively.