Abstract
Effectiveness of Orius strigicollis (Poppius) and Amblyseius cucumeris (Oudemans) as natural enemies against thrips were evaluated on greenhouse green pepper, sweet pepper and cucumber respectively. Control efficacy was calculated by the formula, $(D_{control}-D_{treatment})/D_{control}{\times}100$, where $D_{control}$ is the average density of thrips on the plots in which any natural enemy was not released and $D_{treatment}$ is the average density of thrips on the plots in which natural enemies were released respectively. As a result, control efficacies of O. strigicollis against Frankliniella occidentalis (Pergande) on green pepper and sweet pepper were $14.3{\sim}99.5%$ and $21.6{\sim}98.3%$, respectively. In addition, control efficacy of it against Thrips palmi Kany on cucumber was 61.2-74.4%. Control efficacies of A. cucumeris against F. occidentalis on green pepper and sweet pepper were $12.9{\sim}38.3%$ and $17.1{\sim}87.0%$, respectively. Control efficacy of it against T. palmi on cucumber was $90.4{\sim}97.4%$. Field evaluation showed that the prompt applications of natural enemies were effective to reduce the density of thrips. In detail, to control F. occidentalis effectively on green pepper and sweet pepper in spring season, five to six individuals of O. strigicollis per crops should be released three to six times continuously. To control T. palmi effectively on cucumber in autumn, more than 100 individuals of A. cucumeris per crop should be released four times repeatedly.
시설재배 꽈리고추, 피망에 발생하는 꽃노랑총채벌레와 오이에 발생하는 오이총채벌레의 생물적 방제를 위하여 작물별로 천적인 으뜸애꽃노린재(Orius strigicollis) 방사구, 오이이리응애(Amblyseius cucumeris) 방사구, 무방사구를 두어 총채벌레 밀도억제 효과를 조사하였다. 으뜸애꽃노린재에 의한 총채벌레의 밀도억제효과 산출 식은 (무처리구 밀도-처리구 밀도)/무처리구 밀도 ${\times}$ 100으로 하여 조사시기별로 각각 구한 결과, 꽈리고추에서 으뜸애꽃노린재 방사구는 최하 14.3%에서 최고 99.5%, 오이이리응애 처리구는 $12.9{\sim}38.3%$였고, 피망에서 으뜸애꽃노린재 처리구는 $21.6{\sim}98.3%$, 오이이리응애 처리구는 $17.1{\sim}87.0%$였다. 오이에서 으뜸애꽃노린재 처리구는 $61.2{\sim}74.4%$, 오이이리응애 처리구는 $90.4{\sim}97.4%$를 보였다. 따라서 봄 작기 꽈리고추와 피망에 발생하는 꽃노랑총채벌레는 발생 초기 으뜸애꽃노린재를 주당 $5{\sim}6$마리를 $3{\sim}6$회로 나누어 방사하고, 가을 작기 오이에 발생하는 오이총채별레는 발생초기 오이이리응애를 주당 100마리씩 4회 정도 방사하면 효과적임.
