4种剂型噻虫胺对柑橘木虱的田间防治效果

2018年-2019年,采用田间小区试验评价了噻虫胺4种剂型(30％悬浮剂、18％包埋颗粒剂、13.5％壳聚糖微球和0.5％颗粒剂)及2种施用方式(喷雾和沟施)对柑橘木虱的防治效果.结果 表明:叶面喷施30％噻虫胺悬浮剂60 mg/kg处理对幼年树及成年树上柑橘木虱的控制效果好且持效期约30 d,而药后46～96 d的...

Control efficacy of clothianidin with four formulations against the Asian citrus psyllid, Diaphorina citri under field conditions

Field plot experiments were conducted to evaluate control efficacy of clothianidin with four formulations including 30% suspension concentrate (SC), 18% embedded granules (EGr), 13.5% chitosan microspheres (CsMs) and 0.5% granule (GR) using two application methods including foliar spray and furrow application against the Asian citrus psyllid, Diaphorina citri Kuwayama on citrus trees in 2018-2019. The results showed that a single foliar spray of clothianidin 30% SC at a dosage of 60 mg/kg could obviously control D. citri on young and mature trees within 30 days, but its control efficacy was significantly reduced 46-96 days after treatment, and it had difficultly in controlling the pest. Good control efficacies of clothianidin 18% EGr and 13.5% CsMs at dosages of 0.1-0.2 g/tree against D. citri could be achieved within 96 days after furrow application mixed with poisonous soil around the roots of the young tree. This pest was obviously controlled by clothianidin 0.5% GR at a dosage of 0.1 g/tree within 46 days, but it was difficult to control 66-96 days after furrow application. At the dosage of 0.1 g/tree, 7-30 days after furrow application, the control efficacies of clothianidin 0.5% GR were the highest, followed by 18% EGr, and those of 13.5% CsMs were slightly lower, 46-96 days after furrow application, the control efficacies of 18% EGr were the highest, followed by 13.5% CsMs, and those of 0.5% GR were slightly lower. As for the mature trees, clothianidin 18% EGr and 13.5% CsMs at dosages of 0.6-0.8 g/tree could effectively control D.citri, and the better control efficacies of clothianidin 0.5% GR at a dosage of 0.2 g/tree were achieved 89 days after furrow application. At the dosage of 0.2 g/tree, the differences of control efficacies of clothianidin among 18% EGr, 13.5% CsMs and 0.5% GR on mature trees were similar with those on young trees. Additionally, if the application formulation, dosage and method were the same, the control efficacies of clothianidin were slightly lower than those of thiamethoxam on young and mature trees. In summary, these results suggested that a single foliar spray application of clothianidin 30% SC at a dosage of 60 mg/kg could be recommended to control D.citri at the infestation peak in the field. One-time furrow application mixed with poisonous soil of clothianidin 18% EGr at a dosage of 0.2 g/tree was applied in order to effectively control D.citri during the initial period of infestation on young citrus trees, while its dosage should be added to 0.6 g/tree on mature citrus trees.