除草剂低剂量处理的高产效果

High Yielding Effect with Reduced Rates of Herbicide Treatment

为了比较常规剂量和低剂量除草剂对稻田稗草、丛生千金子、碎米莎草、红根莎草和鳢肠的防除效果及其对产量的影响,在水稻和杂草的不同生长阶段以常规剂量和低剂量(口恶)草丙分别作单、连续和结合敌稗复合式处理。早期使用敌稗,随后在水稻3叶期使用低剂量(口恶)草丙0,08或0.11kgai/ha 处理,均获得优级杂草防除率和最高水稻产量。(口恶)草丙单一或连续使用能有效防除稗草和丛生千金子,但不能防除莎草和鳢肠。(口恶)草丙低剂量和常规剂量处理分别发生轻微和中度水稻植株损伤,但处理后19天,水稻恢复正常。

Standard and reduced rates of fenoxaprop[ethyl 2-(4-(6-chloro-2- benzoxazolyloxy)-phenoxy)propanasate]was applied singly,sequentially and following propanil (3',4'-dichloropropionamilide)at different growth stages of rice and weeds to compare standard and reduced rates of the herbicide treatments for control of barnyardgrass(Echinochloa crus-galli (L.)Beauv.),bearded sprangletop(Leptochloa fascicularis(Lam.)Gray),rice flatsedge (Cyperus iria L.),red-root flatsedge(Cyperus erythrorhizos),and Eclipta(Eclipta alba(L.) Hassk)in rice(Oryza sativa L.cv.Tebonnet).Excellent control of all weeds and the highest grain yield were obtained with early post-emergence(2-leaf barnyardgrass)treatment of propanil at 3.4kg ai/ha followed by fenoxaprop at reduced rates of 0.08 and 0.11kg ai/ha ap- plied to rice in the three-leaf stage.Fenoxaprop applied singly or sequentially controlled barnyardgrass and bearded sprangletop,but failed to control flatsedges or Eclipta.Rice plants in- jury was slight to moderate with standard and reduced rates of fenoxaprop,the crop recovered by 19 days after treatment.