精异丙甲草胺不同剂量和苦荞不同种植密度的除草和产量效应

Effects of S-metolachor Dosage and Planting Density on Weeding and Yield of Fagopyrum tataricum

为了筛选苦荞田中适宜的96%精异丙甲草胺乳油剂量和种植密度的配置,以云荞1号为材料,设置人工除草(CK1)、不除草(CK2)以及96%精异丙甲草胺乳油剂量[分别为750 mL/hm^2(C1)、1050 mL/hm^2(C2)、1350 mL/hm^2(C3)、1650 mL/hm^2(C4)]和种植密度[95万株/hm^2(A1)、145万株/hm^2(A2)、195万株/hm^2(A3)]配置处理,研究96%精异丙甲草胺乳油不同剂量和种植密度对苦荞田中的除草效应及苦荞产量的影响。结果表明,随着96%精异丙甲草胺乳油剂量的增加,禾本科草和阔叶草的株数防效和鲜重防效表现值增大,并且对禾本科草的防效大于阔叶草。当96%精异丙甲草胺乳油剂量为C3和C4时,各种植密度下禾本科草的株数防效和鲜重防效大于50%,能抑制苦荞出苗并影响其产量。当种植密度达到A3时,96%精异丙甲草胺乳油剂量为C3和C4下的苦荞产量很高,并且显著高于人工除草对照处理;但考虑到大量使用化学除草剂会导致农药残留,建议使用96%精异丙甲草胺乳油C3剂量。由于96%精异丙甲草胺乳油用量与土壤条件有密切的关系,因此不同地区要选好适合当地土壤的96%精异丙甲草胺乳油用量。

A field experiment was established to select a suitable combination of S-metolachor 96%EC dosage and planting density in Yunqiao No.1 tartarian buckwheat(Fagopyrum tataricum).Treatments included hand weeding,non-weeding,and S-metolachor 96%EC at several doses of 750 mL/hm^2(C1),1050 mL/hm 2(C2),1350 mL/hm^2(C3),1650 mL/hm^2(C4),and planting densities of 0.95 million plants/hm^2(A1),1.45 million plants/hm^2(A2),and 1.95 million plants/hm^2(A3).Efficacy based on weed density and fresh weight improved as S-metolachor dose increased;the herbicide better controlled Gramineae than broadleaf weeds.At high doses(C3 and C4),efficacy of S-metolachor was above 50%despite planting density,but buckwheat emergence was inhibited and its yield decreased.At the highest planting density(A3),yield of tartarian buckwheat treated with the herbicide at high dose(C3 and C4)was very high,similar to that obtained at the suitable planting density and artificial weeding.Considering that a large number of chemical herbicides will lead to pesticide residues,it is recommended to use the S-metolachor 96%EC at 1350 mL/hm 2.However,there was a close relationship between S-metolachor 96%EC dosage and soil conditions,so it is necessary to select the appropriate S-metolachor 96%EC dosage for the local soil in different regions.