인삼줄기버섯파리의 생물학적 특성 및 정향과 팔각회향 유래 화합물들의 살충활성

Abstract

The fumdamental information of biology and the insecticidal activities of constituents identified in Syzygium aromaticum bud and Illicium verum fruit methanol extract and hydrodistillate against third instar larvae of Bradysia procera and its possible mode of action. In addition, phytotoxicity and control efficacy of S. aromaticum bud-derived materials are also examined. The female of B. procera laid approximately 160 eggs and average egg period was 6 days, approxemately. An average weight of first to third instar larva were 1.3, 8.1 and 81.0 μg, respectively. An average length and width of first to third instar larvae were 608, 1,670, 4,330 and 140, 510, 792 μm. The male forth instar larva of the weight, length and width were 145 μg, 7,224 and 875 μm, and female were 166 μg, 8,081 and 1,017 μm, respectively. The larval periods of female and male were 16.1 and 15.3 days, respectively. The pupal weigh, length and width of male and female were 99 μg, 3,972, 1,109 μm and 106 μg, 4,681 and 1,175 μm, respectively. Adult male and female emerged from pupa on 6.7 and 7 days on after pupation, and their longevities are 5.3 and 6.8 days, respectively. Comparison of develpopmental characteristics and lifecycles of B. procera among ginseng and garlic stem, there wa no significant difference, whereas survival rate was significant higher on ginseng stem than on garlic stem supplied. Seasonal occurrences of B. procera adult population observed mainly three peaks, mid- and late-June and August. The damage symptoms to ginseng were described. The toxicity and mechanism of action of constituents from S. aromaticum bud and I. verum fruit against third-instar larvae and eggs of B. procera. Also, phytotoxicity, control efficacy and anti-oviposition of S. aromaticum bud methanol extract and hydrodistillate in ginseng fields were examined. In a filter-paper mortality bioassay, methyl salicylate (LC50, 5.26 μg/cm-2) from S. aromaticum bud and estragole (LC50, 4.68 μg/cm–2) from I. verum fruit were the most toxic compound. Egg hatch of methyl salicylate and estragole were inhibited 97 % at 11.7 μg/cm-2 and 95 % at 30 μg/cm-2, respectively. These constituents were consistently more toxic in closed versus open containers, indicating that toxicity was achieved mainly through the action of vapor. The mechanism of larvicidal action of methyl salicylate, 2-nonanone, eugenol, and eugenyl acetate of from S. aromaticum bud constituents might be due to interference with the octopaminergic system. α-Pinene and α-Copaene might act on acetylcholinesterase. In addition, estragole from I. verum fruit was a potent acetylcholinesterase (AChE) inhibitor, and the cyclic AMP level induced by this compound was slightly lower than that induced by octopamine alone. This finding indicates that estragole might act on both the AChE and octopaminergic receptors. trans-Anethole was a weak AChE inhibitor.

In phytotoxicity test, S. aromaticum bud-derived materials observed any phytotoxic symptoms. In control efficacy test, bud hydrodistillate revealed 56 and 54 % control efficacy at 0.484 g/m-2 on 7 and 14 DAT (day after treatment) in Yeoju area, respectively. In Icheon area, 61 and 52 % control efficacy at 0.484 g/m2 on 7 and 14 DAT respectively. The anti-ovipostion effect of bud hydrodistillate observed 51 and 44 % at 0.484 g/m-2 on 7 and 14 DAT, respectively. The anti-oviposition of hydrodistillate was similar or more effective to that of clothianidin, dichlorvos, emamectin benzoate and thiamethoxam but was lower than that of cypermethin. In field evaluation of S. aromaticum bud-dervided materials and its insecticide mixtures of four insecticides against B. procera, almost of single treatments of bud-derived materials were observed significantly different of control efficacy and anti-oviposition effect compared with insectides mixtures. However, bud hydrodistillate + cypermethrin mixture showed 94 and 93 % control efficacy and 95 and 93 % anti-oviposition effect on 7 and 14 DAT, respectively.

Futher studies with possible applications of S. aromaticum bud and I. verum fruit derived products as potential larvicides and ovicides for the control of B. procera populations are warranted.