孔祥男 张一 丁伟

摘要 为明确不同除草剂茎叶处理对旱直播水稻田旱生阔叶杂草防除及安全性的影响，采用随机区组试验设计，选用30% 2，4-滴丁酸钠盐AS、84%氯酯磺草胺WG、480 g/L灭草松AS 3种除草剂在水稻4叶期、5叶期施用，施药后每间隔7 d测定杂草株防效、鲜重防效和水稻目测药害，同步测定水稻生长指标和抗逆酶活性。结果表明：30% 2，4-滴丁酸钠盐AS 900.0 g/hm2在水稻4叶期的杂草防效最佳，第28天杂草株防效及鲜重防效仍可达93.55%和96.42%，且对大龄鸭跖草防效显著，施药后水稻生长与人工除草相比无显著差异。叶片SOD、POD活性和MDA含量均先升后降，至施药后28 d恢复正常。30% 2，4-滴丁酸钠盐AS 900.0 g/hm2可高效防除阔叶杂草，该药剂在水稻4叶期和5叶期施用对旱直播水稻安全。

关键词 水稻; 旱直播; 除草剂; 杂草防效; 安全性

中图分类号： S 451.22

文献标识码： B

DOI： 10.16688/j.zwbh.2020337

Control effect and safety evaluation of three herbicides on broadleaf weed in direct-sowing dry paddy fields

KONG Xiangnan， ZHANG Yi， DING Wei*

（College of Agriculture， Northeast Agricultural University， Harbin 150030， China）

Abstract

This study aims to clarify the effects of different herbicides on the control of weeds and the safety to rice after post-emergence application in direct-sowing dry paddy fields by using the randomized block group field trial design. Three herbicides of 2，4-D sodium salt， cloransulam-methyl 84% WG and bentazone 480 g/L AS were applied in the four-leaf or five-leaf stages of rice. The control effect of the weed plants， the control effect of the weed fresh weight， the visual damage of herbicides to rice， the rice growth and antioxidant enzyme activity were determined every seven days after post-emergence application. The results showed that  2，4-D sodium salt 30% AS at 900.0 g/hm2was the best in weed control in four-leaf stage， and the control efficacies of the weed plants and the weed fresh weight were still 9355% and 9642% when 28 days after application， respectively. Moreover， it had significant control effect on older Commelina communis. There is no significant difference compared with manual weeding control treatment in rice growth after herbicide application. The SOD， POD activity and MDA content of the leaves increased first and then decreased， and returned to normal 28 days after application. 2，4-D sodium salt at 30% AS 900.0 g/hm2 can effectively control broadleaf weeds and is safe to rice when applied at the four-leaf or five-leaf stage of rice plant.

Key words

rice; dry direct seeding rice; herbicide; weed control; safety

水稻旱直播是一种采取机械旱种、一次性施肥、全生育期干湿交替管理的栽培方法[1]。该项技术由于省却了育秧、插秧等大量需要人力的操作，可实现水稻生产全程机械化，从而节省大量的劳动力和水资源。水稻生产经济效益高而逐渐受到生产者的高度重视[2-3]。

然而水稻旱直播不同于水直播的突出问题是：在土壤干湿交替管理条件下，水生和旱生杂草均有发生，杂草种类多、发生密度大，危害严重且防除困难，成为水稻旱直播推广应用的瓶颈问题[4]。虽然已有的水直播稻田化学除草剂可高效、安全防除水生杂草[5-6]，然而旱直播水稻田大量發生的旱生恶性阔叶杂草……