Graduate School of Science & Technology, Chiba University, 1-33 Yayoi-cho, lnage-ku, Chiba 263-8522, Japan.
J Insect Sci. 2009;9:1-13. doi: 10.1673/031.009.5201.
The effects of extracts of sesame, Sesamum indicum L. (Liamiales: Pedaliaceae), and whole leaves of some selected cultivars of sesame were tested using a natural host Spodoptera litura (F.) (Lepidoptera: Noctuidae). Indices taken using the immature stages include; diet utilization, growth and development and induction of detoxification enzymes. The results indicate that S. litura generally selects its food amongst cultivars within 6 hours after food presentation. Growth and development of the insect is controlled also by plant acceptability and quality. Although all the cultivars tested significantly limit insect growth and development the variety 56S-radiatum did not allow a complete life cycle as pupation from first instar stage was 0%. Generally the crucial period for immature S. litura was the larval period, especially the first two instars where the weight of an insect fed on an experimental diet was three times lower than that of a control diet. The larval developmental period was greater than 40 days as compared to 17 days for insects fed a control diet. S. litura also had lowered efficiency in utilizing ingested food, from a low of 13% in a sesame cultivar to 45% in the control diet. The key detoxification enzyme was a glutathione s-transferase that was confirmed by a 6-fold increase between S. litura fed a plant cultivar vs. a control diet towards the substrate 1,2-dichloro-4-nitrobenzene. First and second instars of S. litura have a relatively reduced detoxification of enzymes in response to plant cultivar diets leading to low survival. A 3% v/w crude extract of the cultivars increased enzyme induction towards all the tested substrates.
芝麻（芝麻科芝麻属）提取物和部分精选芝麻品种的全叶对斜纹夜蛾（鳞翅目夜蛾科）的天然寄主进行了测试。采用未成熟阶段的指数包括：饮食利用、生长发育和解毒酶的诱导。结果表明，斜纹夜蛾通常在食物呈现后 6 小时内从品种中选择食物。昆虫的生长发育也受植物可接受性和质量的控制。虽然所有测试的品种都显著限制了昆虫的生长和发育，但品种 56S-radiatum 并不允许完全的生命周期，因为第一龄期的蛹化率为 0%。一般来说，斜纹夜蛾未成熟的关键时期是幼虫期，特别是前两个龄期，在实验饮食中饲养的昆虫的体重比对照饮食低三倍。幼虫发育期超过 40 天，而对照饮食中饲养的昆虫发育期为 17 天。斜纹夜蛾对摄入的食物的利用效率也降低了，从一个芝麻品种中的 13%到对照饮食中的 45%。关键的解毒酶是谷胱甘肽 s-转移酶，这通过与对照饮食相比，斜纹夜蛾在植物品种上喂养时，对 1,2-二氯-4-硝基苯的底物的酶增加了 6 倍得到证实。斜纹夜蛾的第一和第二龄期对植物品种饮食的解毒酶相对减少，导致存活率低。品种的 3%（w/w）粗提取物增加了对所有测试底物的酶诱导。
