Evaluation of Control Efficacy of Some Insecticides to the Larvae of Holotrichia parallela in Summer Soybean Field

[Aims] The paper aims to select the effective pesticide to control the Larvae of Holotrichia parallela in summer soybean field. [Methods] The control efficacies of 5 chemicals and 3 fungal reagents were tested by covering network and artificial inoculation after application of 15 and 30 days. [Results] The results indicated that the control efficacy of chlorpyrifos 30% SC and chlorpyrifos 48% EC were both more than 90%. The control efficacy of Beauveria bassiana powder(2×107spores/g) was 90.83% for 15 days and 68.02% for 30 days after treatment, respectively. [Conclusions] The results of control efficacies showed that chlorpyrifos was better than phoxim and B. bassiana was better than Metarhizium anisopliae. Aqueous capsule suspension could prolong the effective duration of insecticides.