본 연구는 시설토마토 재배지에서 push-pull 전략을 이용해 담배가루이와 천적곤충의 행동을 제어함으로써 담배가루이(Bemisia tabaci)를 친환경적으로 방제하기 위한 기술을 개발하고자 수행하였다. 담배가루이는 노란색에 유인율이 가장 높았으며, 520 nm의 광원에는 유인반응을 복합광원인 450 + 660 nm의 광원에는 회피반응을 보였다. 천적곤충인 담배장님노린재(Cyrtopeltis tenuis)와 미끌애꽃노린재(Orius laevigatus)는 모두 520 nm의 광원에 가장 높은 유인반응을 보였다. 휘발성 물질로는 ocimene과 carvacrol에 대해 기피반응을, methyl isonicotinate에는 유인반응을 보였다. 토마토 온실에 메밀을 투입하였을 경우 천적곤충인 담배장님노린재의 밀도는 무처리 대비 15일간 약 16배로 높게 유지되었다. Push-pull 세부전략들을 종합 처리한 결과, 처리 50일 경과 후 담배가루이의 트랩당 밀도는 무처리 대비 3배 이상 낮게 나타났으며, 이에 따른 시기 별 방제효과는 시간이 경과함에 따라 증가하는 경향을 보인 가운데 최고 68.7%였다.
This study was conducted to develop a technology for environmentally friendly control of Bemisia tabaci by a push-pull strategy in tomato greenhouse. B. tabaci was most attracted to the light source of 520nm, whereas it showed an avoidance response to the complex light treatment of 450+660nm. Two natural enemies, Nesidiocoris tenis and Orius laevigatus were attracted to 520nm. B. tabaci was repellent to volatile organic compounds, ocimene and carvacrol, while methyl isonicotinate showed attractant response. When buckwheat was added into the greenhouse, the density of N. tenis was maintained at about 16 times higher for 15 days. As a result of the combined treatment of push-pull strategy, the density of B. tabaci was 3 times lower and the control effect increased with time and reached up to 68.7%.
We evaluated three previously known repellents of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), i.e., carvacrol, cis-jasmone, and methyl jasmonate for the attraction of commercialized predators, Orius laevigatus (Fieber) (Hemiptera: Anthocoridae), and native predator, O. minutus (L.), in Y-tube olfactometer. Higher proportion of O. laevigatus (mated unfed adult females) moved to the arm of methyl jasmonate or cis-jasmone than the arm of clean air. However, O. minutus did not show any significant preference to the chemicals tested. These results suggest that, among the tested chemicals, methyl jasmonate or cis-jasmone would be a good attractant for O. laevigatus.
Orius spp. (Heteroptera: Anthocoridae) prey on small arthropods such as aphids, thrips, whitefly, and mites both in greenhouse and field. Use of chemical attractants to natural enemies can improve the efficacy of biological control through push-pull strategy. We compared attractiveness of three synthetic herbivore-induced plant volatiles (HIPVs), i.e., nonanal, methyl anthranilate, and methyl salicylate for thrips natural enemies, O. laevigatus (Fieber) and O. minutus (L.), in Y-tube olfactometer. Mated unfed adult females of O. laevigatus showed higher choice rate to methyl anthranilate or methyl salicylate than nonanal. Orius minutus showed higher choice rate to methyl anthranilate than methyl salicylate or nonanal. These results suggest that, among the three HIPVs, methyl anthranilate can be used for the attractant of both O. laevigatus and O. minutus.
The sweet potato whitefly, Bemisia tabaci (Gennadius) and the western flower thrips, Frankliniella occidentalis (Pergande) are major insect pests that causes crop damage worldwide by piercing leaves, sucking sap and transmitting numerous plant viruses. A new strategy for IPM, the push–pull method uses a combination of repellent intercrops (push) and alluring trap plants (pull) to manipulate the distribution of insect pests and control their populations. So, we surveyed the responses of these pests of tomato to several plants in green house. Lavandula angustifolia, Petunia hybrid, Ocimum basilicum and Rosmarinus officinalis showed about forty-percent push response to F. occidentalis in tomato. However, Gypsophila paniculata attracted the F. occidentalis in tomato on the contrary. Pelargonium tomentosum showed about fifty-percent push response to B. tabaci in tomato. However, Mentha spicata and Gypsophila paniculata attracted the B. tabaci in tomato. The utilization technique of these plants should be more inspected in further study.