机插秧稻田二次封闭控草应用技术

Application Technology of Two Times of Closed Weed Control in Mechanical Transplanted Rice Field

稻田草害是机插秧生产中最严重的问题。传统水稻田"一封二杀三补"控草策略策略已经不能适应机插秧的除草要求。本文综合小区试验和大区示范,针对不同栽培条件下的土壤和杂草情况,提出"二封一补"的除草对策。3年试验示范结果表明,土地平整后插秧前使用57%苄·丙·异丙隆可湿性粉剂1 500~1 800 g/hm^2进行第1次封闭处理,插秧后10 d用50%苄·丁·异丙隆可湿性粉剂1 200~1 500 g/hm^2进行第2次封闭,既能有效控制早期杂草为害,保证秧苗安全,又能延长对杂草持续控制作用,提高水稻产量。在2次封闭基础上,针对不平整地块和烤田后抗性杂草发生情况,提出相对应的补治措施。

Paddy weeds are the most serious problems in transplanted rice production. Traditionally,the weed control strategy has three steps: a single pre-emergence herbicide application followed by a post-emergence herbicide treatment and an optional late post-emergence chemical spray,if required,to eliminate escapes. But this treatment combination has been unable to meet the requirements for weed control in mechanically transplanted fields. In this paper,combined with the district test and large area demonstration,aiming at one shot for pre-emmergence and weeds under different cultivation conditions,we put forward a new strategy that taking two times of closed weed control,and then checking that leaks and filling a vacancy to the weeds. After three years of experimental demonstration,the proposed strategy proved effective in controlling early weed damage,ensuring the safety of seedlings,providing continuous control of weeds,and increasing grain yield. Thus we recommend using 1 500 ~ 1 800 gram per hectare of Bensulfuron methyl·Pretilachlor· Isoproturon 57% WP after soil preparation but before transplanting as the first time of closed weed control followed by the application of Bensulfuron methyl· Butachlor· Isoproturon 50% WP( at 1 200 ~ 1 500 gram per hectare) 10 days after transplanting as the second time of closed weed control. Based on the two times of closed weed control,we put forward the corresponding treatment measures that aim at the occurrence of weeds on the high land or the resistant weeds.