氟吡菌酰胺不同施药方式对水稻拟禾本科根结线虫的防治效果

Evaluation on the control effect of fluopyram on the root-knot nematode in rice with different spraying methods

为评价41.7%氟吡菌酰胺悬浮剂防治水稻拟禾本科根结线虫Meloidogyne graminicola的应用潜力,将氟吡菌酰胺与吡虫啉种衣剂混合后采用种子包衣法及喷洒法研究其对水稻拟禾本科根结线虫的田间防效,并测定了不同施药方法对水稻生长和产量的影响。结果表明,氟吡菌酰胺4.2、8.3、12.5 g (a.i.)/kg种子与吡虫啉18.0 g (a.i.)/kg种子混合包衣处理,播种后35 d其根结抑制率和防效分别为41.0%～51.8%和47.4%～58.6%,土壤中2龄幼虫减退率为38.6%～40.4%,显著高于单施吡虫啉18.0 g (a.i.)/kg种子处理。水稻播种后连续3次以氟吡菌酰胺250.2、375.3、500.4 g (a.i.)/hm^2进行土壤喷洒,最后1次施药后7 d,其根结抑制率和防效分别为81.0%～89.9%和65.9%～74.3%,土壤中2龄幼虫减退率为65.4%～73.4%,均显著高于对照药剂克百威1 800.0 g (a.i.)/hm^2处理。氟吡菌酰胺各处理对水稻苗期生长均有较好的保护作用,能显著提高千粒重和有效穗数,产量比空白对照增加50.0%～61.2%,保产效果显著。水稻播种后35 d采用氟吡菌酰胺对稻田进行1次喷洒,对水稻具有一定的保护作用,保产效果不明显。表明采用氟吡菌酰胺与吡虫啉混合包衣种子处理及在水稻苗期进行喷洒处理对水稻拟禾本科根结线虫防效显著,具有显著的保产效果。

To evaluate the potential of 41.7% fluopyram SC in controlling Meloidogyne graminicola,field trials were conducted by seed coating combined with imidacloprid FS(flowable concentrate for seed coating) and spraying methods to compare their control efficacy and effects on growth and yield of rice. Compared with the control, seed-coating with fluopyram SC at the rate of 4.2, 8.3, 12.5 g(a.i.)/kg seeds + imidacloprid FS at 18.0 g(a.i.)/kg seeds reduced root galling by 41.0%-51.8%, galling index by 47.4%-58.6%, juvenile densities of M. graminicola in the soil by 38.6%-40.4% at 35 d after sowing,which were significantly higher than that of imidacloprid FS at 18.0 g(a. i.)/kg seeds. Spraying fluopyram three times in the period of seeding at the rate of 250.2, 375.3, 500.4 g(a.i.)/hm^2 reduced root galling by 81.0%-89.9%, galling index by 65.9%-74.3%, juvenile densities of M. graminicola in the soil by 65.4%-73.4% at 7 d after the last application, which were significantly higher than those when spraying carbofuran at the rate of 1 800.0 g(a.i.)/hm^2. Fluopyram treatments exhibited evident efficacy in controlling M. graminicola in the field, and the average yield increased by 50.0%-61.2%, due to improved 1 000-grain weight, effective panicle number per hill. Spraying fluopyram at 35 d after sowing had a certain protective effect on rice, but the yields exhibited no significant difference from that of the negative control. The results indicated that fluopyram could be used to control M. graminicola effectively using seed coating combined with imidacloprid and spraying methods in the period of rice seedling.