水稻穗前稻飞虱省力化防控技术可行性评价

本文研究不同药剂处理水稻种子对稻飞虱的防治效果,以期筛选出对稻飞虱防治效果好、持效期长的药剂及其配套使用技术,为稻飞虱的省力化防控提供科学依据。选择噻虫嗪、呋虫胺、吡虫啉、烯啶虫胺、噻虫胺和氟啶虫胺腈6种药剂分别按照有效药量2、4、6 g/kg进行拌种,测定不同处理对室内及田间稻飞虱的防治效果;同时将噻虫嗪与复合肥混合施用,验证药肥混施对稻飞虱的防治效果及时长。结果表明,室内条件下,以噻虫嗪4 g/kg拌种对褐飞虱的防治效果最好,有效控制时长为45 d左右,防治效果为90.6%;田间条件下,机插秧、直播稻以及旱育秧3种种植方式下,仍以噻虫嗪防治效果最好,有效控制时长分别为65、80、65 d。噻虫嗪与复合肥混合施用,有效药量为240 g/hm^2以上时,药后20 d,防治效果在85%以上,与常规茎叶喷雾防治效果无差异。利用噻虫嗪有效药量4～6 g/kg进行拌种,在稻飞虱发生较轻年份,可有效降低田间稻飞虱种群数量;在稻飞虱发生较重年份,水稻抽穗前采用噻虫嗪药肥混施,控制稻飞虱的持效期为20 d左右,能有效减少稻飞虱的防治次数,实现稻飞虱的省力化、轻简式防控,可在水稻生产中推广应用。

Feasibility evaluation of labor saving control technology ofrice planthopper before heading stage

In order to screen out pesticides with high control efficacy and long lasting effect and provide scientific evidence for labor saving control against rice planthopper, control effects of different chemical pesticides on rice planthopper were investigated by rice seeds dressing. Thiamethoxam, dinotefuran, imidacloprid, nitenpyram, clothianidin and sulfoxaflor were separately mixed with 1 kilogram rice seeds at three effective dosages of 2 g, 4 g and 6 g. Effects were tested indoor and in field. Three kinds of cultural patterns, including mechanical transplanting, direct seedling and dry raised seedling transplanting, were used in the field. Besides, compound fertilizer was mixed with thiamethoxam to test the control efficacy and lasting period. Indoor experiment showed that 4 g thiamethoxam per kilogram seeds had best effect on rice planthopper with the efficacy of 90.6% and the lasting validity period was around 45 d. Field experiments demonstrated that thiamethoxam had the best effect under three cultural patterns, and the lasting validity periods were 65 d, 80 d and 65 d under mechanical, direct and seedling transplant, respectively. Thiamethoxam mixed with compound fertilizer at the dosage of 240 g/hm2 had the control efficacy of over 85% 20 days after application, without significant difference with normal spraying. Application 4-6 g thiamethoxam mixed with 1 kg seeds in the light occurrence years could effectively reduce the field rice planthoppers density, In heavy occurrence years, the lasting validity period of thiamethoxam with compound fertilizer applied before heading stage was around 20 d, which can reduce regular pesticide application times on rice planthopper substantially. Further, the goal of labor saving, concise prevention and control can be reached, and it shall be put into use in rice production.