水稻带药移栽对分蘖期白背飞虱和褐飞虱的防治效果

Control effect of applying pesticides before transplanting to Sogatella furcifera and Nilaparvata lugens at rice tillering stage

室内采用根区施药,田间采用喷雾和根区施药的方式对移栽前1天秧苗用吡虫啉和吡蚜酮进行处理,以获得对水稻分蘖期白背飞虱和褐飞虱具有较好防效的药剂剂量及施药措施。室内试验表明,药后22天50%吡虫啉可湿性粉剂所选剂量中以每hm^2用量300 g对褐飞虱的防效最高,为95.24%;50%吡蚜酮可湿性粉剂所选剂量中以每hm^2用量225 g对褐飞虱的防效最高,为84.13%。田间试验表明,药后33天50%吡蚜酮可湿性粉剂每hm^2用量225 g的喷雾和根区施药对白背飞虱的防效达82.33%~91.10%,对褐飞虱防效达80.80%~89.54%;50%吡虫啉可湿性粉剂每hm^2用量300 g的喷雾和根区施药对白背飞虱的防效达73.91%~93.18%,均具有较高的防效且它们的持效期达33天,超过一般水稻的分蘖期(30天左右)。上述结果表明,采用上述2种药剂的带药移栽可有效控制分蘖期白背飞虱和褐飞虱的发生为害。

Root-zone application of imidacloprid or pymetrozine to seedlings one day before their transplanting in laboratory, and spray and root-zone application in field were determined to find out more effective pesticides doses and control measures to Sogatella furcifera and Nilaparvata lugens at rice tillering stage. The results of laboratory tests showed that the control effect of 50% imidacloprid WP 300 g/hm2 and 50% pymetrozine WP 225 g/hm2 to N. lugens were the highest, reached respectively 95.24% and 84. 13% after 22 d. The results of field trials indicated that, after 33 d, the control effect of 50% pymetrozine WP 225 g/hm2 by spray and root-zone application to S.furcifera reached 82.33% - 91.10% and to N. lugens reached 80. 80% - 89. 54%; The control effect of 50% imidacloprid WP 300 g/hm2 by spray and root-zone application to S.furcifera reached 73.91% - 93.18%, they all had significant effect, which could maintain for more than 33 d, even longer than rice tillering stage （normally is 30 d）. It was suggested that it had good control effect to S. furcifera and N. lugens at tillering stage to apply the above pesticides before transplanting.