- 期刊
高粱除草劑使用方法
Examination of Application Methods of Herbicide in Sorghum
摘要
本研究以萌前除草劑施得圃34% EC、左旋莫多草960 g/L EC分別使用於高粱園，雜草防治之施藥劑量分別為1.5 L/ha及1.2 L/ha，施用施得圃超過15天後雜草防治效果漸低，防治率低於70%，防效時間較短，施用左旋莫多草後30天，防治雜草之效果仍可達80%，防效時間較長。以不同的施藥與播種間隔時間為處理組，施用萌前除草劑施得圃及左旋莫多草後第0、3天播種，高粱幼苗出土率低於50%，施藥後7天後再行播種，幼苗出土率約86-90%受藥劑影響較低，且株高受抑制之情形亦可恢復。因使用之萌前除草劑已先影響其幼苗出土率，故高粱之單位面積產量亦受影響，以施藥與播種間隔日數為7天之處理下，單位面積產量最高。萌後除草劑則以殺芬草70%水分散性粒劑，施藥量為72 g/ha，於高粱播種後第14、21及28天施藥，日射量高時，其防除闊葉雜草之效果較高。施用萌後除草劑之處理，顯著較不除草對照組之產量高，有使用萌後除草劑之必要性。綜合殺芬草防除效果、高粱植株生長情形及產量調查結果，建議以播種後21天於田間施用殺芬草，防治率可達90%以上，且高粱生產不受抑制，屬有效且安全之施藥時機。
並列摘要
The spectrum of weeds in Sorghum fields is dominated by Gramineae, Cyperaceae, and broad-leaved weeds. Due to the known sensitivity of Sorghum to herbicides, this study evaluated two registered pre-emergence herbicides applied on day 0, day 3, and day 7 before Sorghum sowing. Our results revealed that the application of 34% pendimethalin EC at 1.5 L/ha and 960 g/L S-metolachlor EC at 1.2 L/ha to a Sorghum field 7 days before sowing did not affect Sorghum growth or yield. Furthermore, the application of post-emergence herbicide 70% saflufenacil WG at 72 g/ha 21 days after Sorghum sowing effectively controlled weeds without affecting the growth and yield of Sorghum. Weed control rate reached over 90%, and the number of grains per panicle as well as the weight of grains increased by 7% compared with traditional weeding methods.