Selvan Karchikumar, Ramiah Nalini, Balakrishnan Usha Rani, Mariappan Paramasivam, Krishnasamy Suresh, Karunanandham Kumutha, Richard Jasmine Juliet
Department of Agricultural Entomology, Agricultural College and Research Institute (TNAU), Madurai, Tamil Nadu, India.
ICAR- Krishi Vigyan Kendra (TNAU), Virinjipuram, Tamil Nadu, India.
J Chem Ecol. 2025 Sep 11;51(5):91. doi: 10.1007/s10886-025-01645-8.
Groundnut plants subjected to root herbivory by Odontotermes obesus exhibited significant changes in the behavioural responses of Spodoptera litura, characterized by reduced oviposition rates and modified feeding preferences compared to healthy plants. Our findings provide strong evidence that groundnut plants under termite attack mobilized both metabolic and volatile defenses to mitigate further herbivory, supporting the defense induction hypothesis. The elevated levels of phenols, sugar alcohols (D-Pinitol, D-Allose, D-(+)-Xylose), and insecticidal fatty acids (9-Octadecenoic acid, 10-Undecenoic acid) demonstrate a coordinated shift in primary metabolism aimed at reducing herbivore performance. Simultaneously, the altered volatile organic compound emissions (alkanes, alkenes, tetradecane) suggest an indirect defensive strategy, potentially recruiting natural enemies or disrupting host-finding cues of S. litura. These findings demonstrate that below-ground termite herbivory induces significant metabolic shifts in plants, which in turn modulate S. litura oviposition behaviour and larval feeding preferences, highlighting a complex cross-trophic interaction between root and shoot herbivores.
遭受黑翅土白蚁根系取食的花生植株，斜纹夜蛾的行为反应出现了显著变化，与健康植株相比，其产卵率降低，取食偏好改变。我们的研究结果提供了有力证据，表明遭受白蚁攻击的花生植株调动了代谢防御和挥发性防御来减轻进一步的取食危害，支持了防御诱导假说。酚类、糖醇（D-松醇、D-阿洛糖、D-(+)-木糖）和杀虫脂肪酸（9-十八碳烯酸、10-十一碳烯酸）水平的升高表明初级代谢发生了协同转变，目的是降低食草动物的性能。同时，挥发性有机化合物排放的改变（烷烃、烯烃、十四烷）表明了一种间接防御策略，可能是吸引天敌或扰乱斜纹夜蛾的寄主定位线索。这些发现表明，地下白蚁的取食会诱导植物发生显著的代谢变化，进而调节斜纹夜蛾的产卵行为和幼虫取食偏好，突出了根食草动物和茎食草动物之间复杂的跨营养相互作用。
