Fenvalerate, cypermethrin, furathiocarb 및 prothiofos에 대해 각각 581, 18, 19, 11배의 저항성을 보인 진주계통과 fenvalerate와 furathiocarb에 대해 각각 38배와 9배의 저항성을 나타내고 있는 함양.서상계동을 bifenthrin과 prothiofos의 혼합조합으로 방제하기 위해 실내 엽침지법과 포장방제시험을 수행하였다. Bifenthrin 1EC와 prothiofos 50EC을 1:50으로 혼합하여 실내엽침지법으로 처리하였을 때 공력계수가 273.2로 최고점에 도달한 후 급격히 감소하는 양상을 보였다. 침지법에서 가장 효과적이었던 혼용비율의 조합을 함양.서상현지 농가에서 실증시험을 수행한 결과, 처리구에서 처리약량을 절반으로 줄였음에도 배추좀나방의 방제효과가 농가관행구와 마찬가지로 우수하였다. 또한 이 조합은 여러가지 대표적인 살충제에 대해 높은 저항성을 나타내고 있는 진주지역계통에 대해서도 합리적인 농약혼합으로 저항성문제에 적절히 대처할 수 있음을 보여주었다.

Mixture study of bifenthrin and prothiofos was conducted to control insecticide resistant diamondback moth (DBM), Plutella xylostella, which had shown 581, 18, 19, 11 fold resistance to fenvalerate, cypermethrin, furathiocarb, and prothiofos in Chinju strain, respectively and 38 and 9 fold resistance to fenvalerate and furathiocarb in Seosang strain, respectively. Optimal mixture ratios of bifenthrin and prothiofos was selected against Seosang strain of DBM by leaf dipping method in laboratory and by field test. Maximum co-toxicity coefficient by dipping method was shown at a ratio of 1:50 mixture of bifenthrin 1EC and prothiofos 50EC in active ingredient(a.i.) by 243.2 and then suddenly decreased. The mixed formulation from the dipping test was examined at the cabbage field of Seosang, Hamyang. Although insecticides were reduced to half, control efficacy was similar to farmer's conventional method. In addition, the mixture combination was also more effective against Chinju DBM population which had very high level of resistance to several representative insecticides. Mixture methods of insecticides will be effective countermeasures to the resistance problem of pests.

• Bu Keun CHUNG
• Soo Woong KANG
• Ho Yul CHOO