光活化成分α-三联噻吩对红火蚁的致死作用及对其行为的影响

 【目的】明确光活化成分α-三联噻吩（α-T）对红火蚁（Solenopsis invicta Buren）的致死作用和行为影响。【方法】采用Potter喷雾法研究α-三联噻吩经UVA光照后对红火蚁的击倒活性、致死作用及对红火蚁行走、攀附、聚集能力的影响，并应用扫描电镜技术探讨α-三联噻吩对红火蚁光活化影响的作用机理。【结果】100 μg?mL-1 α-三联噻吩经UVA光照90、120和180 min后，对中型工蚁的击倒率分别为93.08%、98.29%和100%，显著高于药剂黑暗处理90、120和180 min后对中型工蚁的击倒率7.41%、18.52%和25.93%；100 μg?mL-1 α-三联噻吩经UVA光照处理30 min，并黑暗放置1、30、60、90、120、150和180 min后，中型工蚁的死亡率分别为6.25%、10.42%、18.75%、29.17%、37.50%、43.75%和52.08%；行走率分别为25.26%、18.75%、10.67%、6.58%、2.83%、2.08%和0；对倒置一次性塑料杯的附着率分别为20.83%、12.50%、6.17%、4.17%、2.01%、1.96%和0；聚集率分别为20.78%、17.19%、10.94%、15.63%、14.06%、27.08%和37.50%；100 μg?mL-1 α-三联噻吩UVA光照处理30 min后，黑暗放置30 min，中型工蚁触角棒节的毛形感受器和刺形感受器的形态发生显著变化，大部分从中下部发生弯曲，呈倒伏状态，并出现明显指向杂乱的现象。【结论】α-三联噻吩对红火蚁中型工蚁具有良好的击倒活性和一定的致死作用，显著降低其行走能力、对杯壁的攀附能力及聚集能力，显著改变触角感受器的形态及指向，光活化成分有望成为防治红火蚁的安全环保新手段。

Behavioral and Lethal Effects of α-terthienyl on the Red Imported Fire Ant (RIFA)

【Objective】 The objective of this study is to define the effects of α-terthienyl on the red imported fire ant (Solenopsis invicta Buren) behavior and lethality.【Method】The behaviors including aggregation, cling ability and walking ability, lethal effect and knock-down activity of α-terthienyl exposed in UVA were researched by potter spray, and the scanning electron microscope was used to probe into the light activity mechanism of α-terthienyl to the red imported fire ant.【Result】When the illumination times were 90, 120 and 180 min, the knock-down rates of the red imported fire ant treated with 100 μg?mL-1 α-terthienyl were 93.08%, 98.29% and 100%, which were higher than those treated without irradiation. After the red imported fire ants were treated with 100 μg?mL-1 α-terthienyl in dark for 90, 120 and 180 min, the knock-down rates of the red imported fire ant were 7.41%, 18.52% and 25.93%, respectively. After they were treated with 100 μg?mL-1 α-terthienyl in irradiation for 30 min, then set into dark for 1, 30, 60, 90, 120, 150 and 180 min, the mortalities of the red imported fire ant were 6.25%, 10.42%, 18.75%, 29.17%, 37.50%, 43.75% and 52.08%, respectively, the walking rates of the red imported fire ant were 25.26%, 18.75%, 10.67%, 6.58%, 2.83%, 2.08% and 0, respectively, the cling rates of the imported fire ant were 20.83%, 12.50%, 6.17%, 4.17%, 2.01%, 1.96% and 0, respectively, and the aggregation rates of the red imported fire ant were 20.78%, 17.19%, 10.94%, 15.63%, 14.06%, 27.08% and 37.50%, respectively. After the red imported fire ants were treated with 100 μg?mL-1 α-terthienyl in irradiation for 30 min and placed in dark for 30 min, the antennal sensilla shape of the red imported fire ant changed significantly. Most of the antennal sensillum presented disordered, lodging and bending phenomen.【Conclusion】 The α-terthienyl possesses the lethal effect and knock-down ability against the red imported fire ant, and can significantlly decrease the aggregation, cling ability and normal walking ability, and also change the shape of the antennal sensilla of the red imported fire ant. The results suggest that the method of using photoactivation composition is expected to become a safe and environment-friendly method for the control of the red imported fire ant.