普通豚草防控药剂筛选

【目的】普通豚草对新疆伊犁河谷地区的生态及旅游产业发展都造成了严重的威胁。本研究于2019年5月和7月中旬筛选218国道沿路林带农田交错生境下防治普通豚草的最适除草剂和施药浓度,旨在为防治普通豚草提供技术指导。【方法】采用田间小区试验,比较药后7、14、30和45 d的株防效、鲜重防效和株高,评价5月中旬8种除草剂的2个施药浓度对约12叶期、株高(6.20±0.13) cm的普通豚草,以及7月中旬21%氯氨吡啶酸AS的5种施药浓度对约20叶期、株高(16.26±0.68) cm的普通豚草的防治效果。【结果】方差分析表明,5月中旬株防效和鲜重防效最高的是75%苯嘧·草甘膦WG 900和1350g·hm~(-2),其次是30%草甘膦AS 5250和6750 g·hm~(-2)、48%三氯吡氧乙酸EC 4170和6255 g·hm~(-2)、21%氯氨吡啶酸AS 300和375 g·hm~(-2),最低的是20%硝磺草酮SC 637.5和750 g·hm~(-2)。7月中旬,21%氯氨吡啶酸AS对普通豚草的株防效和鲜重防效较好浓度是600 g·hm~(-2),药后45 d株防效和鲜重防效分别为69.7%、93.4%,其次是450和525 g·hm~(-2),药后45 d株防效和鲜重防效分别为47.8%、86.4%和51.7%、91.5%。【结论】综合普通豚草种子萌发情况、防治成本、药剂成分及对环境的影响等因素,5月中旬防治伊犁河谷地区林带生境下的普通豚草时,建议施用75%苯嘧·草甘膦WG 900 g·hm~(-2)、30%草甘膦AS 5250 g·hm~(-2)、48%三氯吡氧乙酸EC 4170 g·hm~(-2)、21%氯氨吡啶酸AS 300 g·hm~(-2); 7月中旬防治公路林带生境下的普通豚草时,建议增加药量,施用21%氯氨吡啶酸AS至少525 g·hm~(-2);防治时期上,建议在5月中旬左右进行防控,可大幅降低用药量并方便农事操作。

Screeing of herbicides for controlling Ambrosia artemisiifolia L. in Xinjiang, China

Aim] Ragweed, Ambrosia artemisiifolia L., poses a serious threat to ecology and tourism industry in the Yili River valley in Xinjiang. In this study, we screened herbicides at various concentrations to determine the optimum combination for controlling A. artemisiifolia in mid-May along the forest belt of National Highway 218 and the optimal concentration of 21% aminopyralid AS for use in mid-July to provide standard guidance for controlling A. artemisiifolia.Method] A field plot experiment was conducted using two concentrations of eight herbicides, which were applied at 12 leaf stage of (6.20±0.13) cm tall A. artemisiifolia after 7, 14, 30, and 45 d. In a second experiment, five concentrations of 21% aminopyralid AS were applied to approximately 20 leaf stage of (16.26±0.68) cm tall A. artemisiifolia stand. The plant and fresh weight control effects were evaluated to compare the tested herbicides and their dosages.Result] Repeated measures analysis of variance showed that in mid-May, application of 75% saflufenacil and glyphosate WG at 900 and 1350 g·hm^-2 had the highest control effects on ragweed, followed by 30% glyphosate AS at 5250 and 6750 g·hm^-2; 48% triclopyr EC at 4170 and 6255 g·hm^-2; and 21% aminopyralid AS at 300 and 375 g·hm^-2. The lowest effects were observed for 20% mesotrione SC at 637.5 and 750 g·hm^-2. In mid-July, 21% aminopyralid AS at 600 g·hm^-2 had the highest control effects, causing 69.7% mortality and 93.4% mass loss, respectively, after 45 d. The second highest effects were observed for 21% aminopyralid AS at 450 and 525 g·hm^-2, which were 47.8%, 86.4%, and 51.7%, 91.5%, respectively, after 45 d.Conclusion] Based on a comprehensive consideration of the treatment effects, cost, ingredients, environmental effect, and other factors, the following applications are recommended for controlling A. artemisiifolia along the forest belt:75% saflufenacil and glyphosate WG at 900 g·hm^-2; 30% glyphosate AS at 5250 g·hm^-2; 48% triclopyr EC at 4170 g·hm^-2; or 21% aminopyralid AS at 300 g·hm^-2 in mid-May and 21% aminopyralid AS at 525 g·hm^-2 in mid-July. However, mid-May is a much more appropriate time to control A. artemisiifolia owing to the lower concentration required for control and more convenient agricultural operation.