Efficacy and phytotoxicity of a petroleum spray oil for control of citrus red mite in Jeju island

제주지역에서 귤응애에 대한 Petroleum Spray Oil의 방제효과 및 식물독성

Recently, a new developed petroleiun spray oil(PSO; D-C Tron $Plus^{(R)}$) has been used to control key pests in integrated pest management (IPM) system of citrus orchards in Australia. The efficacy and phytotoxicity of the PSO against the citrus red mite (Panonychus citri) were compared with conventional pesticides (e.g.Tebufenpyrad, Bifenazate and Sun spray oil) in field condition in Jeju. And under PSO mixing spray with some fungicides, the occurrence of phytotoxic symptoms on citrus leaf was investigated. All concentrations of PSO spraying (0.25%, 0.33%, 0.5% and 1.0%) were significantly suppressed the citrus red mite to similar levels of other conventional pesticides. And the spraying of PSO levels ${\geq}0.5%$ was induced not only occurrence of some oil-sucked symptoms on leaf, but also increase of the dropping leaf and fruit rates. As results from mixing PSO spraying test with other fungicides, little burning on new flush shoot was founded only in PSO 1% plus Fluazinam treatment. From the results of this study, with the consideration of pesticidal efficacy and phytotoxicity, 0.25% and 0.33% PSO spraying level will be recommended for the control of citrus red mite during summer season in Jeju.

인축독성 및 잔효성이 낮은 환경친화적인 Petroleum spray oil(PSO; DC-Tron $Plus^{(R)}$)의 살포에 따른 귤응애에 대한 방제효과 및 약해발생에 관하여 포장조건하에서 검토하였다. PSO를 0.25%, 0.33%, 0.5% 및 1%를 처리한 결과, 귤응애에 대한 방제효과는 모든 농도에서 대조약제(tebufenpyrad, bifenazate, sun spray oil)와 비교하여 비슷하거나 뛰어났으며, 약효도 40일 이상 장기간 지속되는 경향을 나타냈다. 그런데 PSO 0.5% 이상 처리시에는 감귤잎에 유침상 증상이 일부 나타났으나 2개월후에 거의 사라졌으며, 낙엽율과 낙과율은 다소 증가하는 경향이었다. 그리고 PSO 1%를 감출 더뎅이병 및 검은점무늬병의 적용약제와 각각 혼용처리한 결과, 더뎅이병 방제약제인 Fluazinam 수화제와 혼용한 경우 일부 신초가 타거나 일부 신엽에 흑점이 발생하였다. 이러한 약효와 약해 결과를 고려해 볼 때 귤응애 방제를 위한 하절기 PSO 적정 살포농도는 0.25% 또는 0.33% 정도일 것으로 판단된다.