Potential and Persistence of the Inhibitory Effect of Sorghum on Weeds

ABSTRACT: The inhibitory interaction between plants may be an important strategy of integrated weed management (IWM). This study aimed to investigate the inhibitory effects of sorghum on phytosociology and infestation of weeds during cultivation and after harvest. An experiment was carried out in the field in a randomized block design in a split-plot arrangement. Plots consisted of sorghum and corn (control) and subplots were composed of different periods of weed community assessment after crop harvest (DAH) (0, 20, 40, 60, and 80 days). An increased number of species and botanical families was observed after harvest. Degradation of sorghum and corn straw reached the stabilization at 60 DAH. Although sorghum has presented a lower amount of straw and soil cover, weed infestation was, on average, 30% lower in relation to areas cultivated with corn. Sorghum showed an inhibitory effect on some weed species, influencing phytosociology, especially during the first 40 DAH, and can be used as part of IWM strategy.

摘要：植物间的抑制作用或许是杂草综合管理（integrated weed management, IWM）的重要策略之一。本研究旨在探究高粱在作物生育期及收获后对杂草植物社会学（phytosociology）特征与杂草滋生的抑制作用。本试验采用裂区设计（split-plot arrangement）与随机区组设计（randomized block design）相结合的田间方案开展，主小区设置为高粱与玉米（对照组），副小区则设置为作物收获后不同天数（days after harvest, DAH）的杂草群落调查时段，分别为0、20、40、60及80天。研究发现，收获后杂草物种数与植物科数量均有所增加；高粱与玉米秸秆的腐解进程在收获后60天时趋于稳定。尽管高粱的秸秆产量与土壤覆盖度均低于玉米，但种植高粱的地块杂草滋生量平均较玉米种植区低30%。高粱对部分杂草物种具有抑制作用，可影响其植物社会学特征，尤其在收获后的前40天内效果显著，因此可作为杂草综合管理策略的组成部分。