苜蓿不同播种行距对防控少花蒺藜草的效果

Study on the effects of different row spacing of alfalfa on Cenchrus pauciflorus control

在少花蒺藜草Cenchrus pauciflorus严重侵染区,采用3种不同行距种植多年生苜蓿Medicago sativa进行生物控制试验,旨在探索有效控制少花蒺藜草扩散技术。结果表明:苜蓿种植第2年,不同播种行距均能够抑制少花蒺藜草的发生数量,其中以行距30 cm的效果最好,减少至1 200株/hm2左右。对于少花蒺藜草形态特征及繁殖特性的影响效果,不同播种行距处理间存在差异,其中在30、40 cm行距处理苜蓿地中发生的少花蒺藜草均表现出胁迫态,播种行距为50 cm时,少花蒺藜草株型多为半直立或匍匐型,分蘖(分枝)能力较强,繁殖能力也较强。综合分析,采取30 cm行距种植多年生苜蓿能够更有效的控制少花蒺藜草肆意扩散,可以在少花蒺藜草防控工作中推广应用。

A biological treatment trial on effects of different row spacing of alfalfa on controlling seriously invaded Cenchrus pauciflorus was conducted. The results showed that the row spacing treatment could reduce the number of C. pauciflorus and the best was 30 cm which decreased the density to around 1 200 hm^2. But the effects on the morphological and reproduction characteristics of C. pauciflorus were difference, these characteristics showed a stressed status in the treatments of 30 cm and 40 cm row spacing. It showed the lower height, fewer branches and seeds. But in treatment of 50 cm row spacing, the average number of branches was over 9, the number of seed setting was over 180 and the reproduction ability was still strong. It could be concluded that 30 cm of row spacing was the best for the control of C. pauciflorus.