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In this study, we investigated the longevity effects of hispidol, a 6,4′‐dihydroxyaurone, using the Caenorhabditis elegans model system. Our lifespan assay data revealed that hispidol could prolong the lifespan of wild‐type worms under normal culture condition. Moreover, hispidol increased the survival rate of the worms against a heat stress condition through up‐regulated expressions of HSP‐16.2. Similarly, hispidol protected worms from paraquat‐induced oxidative stress. We also found that the hispidol elevated the activities of antioxidant enzymes, thereby attenuating the generation of intracellular reactive oxygen species. These results suggest that the enhancement of lifespan and stress resistance by the hispidol treatment might be attributed to its strong in vivo antioxidant capacity and regulation of stress proteins. Further tests on the aging‐related factors revealed that hispidol could regulate the speed of pharyngeal pumping, indicating the association of dietary restriction with the hispidol‐mediated longevity. However, there were no significant alterations in the body length of the worms between the groups. We then investigated the effects of hispidol on body movement and lipofuscin accumulation in aged worms. Interestingly, these healthspan parameters were strongly improved by the hispidol treatment. Our genetic studies showed no significant change in the lifespan of the daf‐16 null mutants by hispidol supplementation. In addition, enhanced nuclear translocation of DAF‐16 was observed in the hispidol‐fed DAF‐16::GFP fused transgenic mutants, suggesting the requirement of DAF‐16/FOXO activation for the longevity effect of hispidol. [ABSTRACT FROM AUTHOR]

The oriental tobacco budworm, H elicoverpa assulta, is a specialist herbivore feeding on a few plants of the Solanaceae family including tobacco. Larval performance and adult oviposition of H . assulta were investigated in a non-host plant, P haseolus vulgaris (Fabaceae) in comparison with two solanaceous host plants, N icotiana tabacum and D atura stramonium. Larvae provided with the P . vulgaris leaf died off at day 15, whereas 50% and 40% of larval populations fed on the leaves of N. tabacum and D. stramonium, respectively, survived at day 15. Larval growth upon feeding showed significant difference between the non-host plant ( P . vulgaris) and the host plants ( N . tabacum and D . stramonium), but it was not significantly different between the two host plants. In the no-choice experiment of oviposition, gravid females laid more eggs in N . tabacum and D . stramonium than in P . vulgaris. When the most likely acceptable host plant, N . tabacum, and the non-host plant, P . vulgaris, were subjected to the choice experiment of oviposition, H . assulta females preferred to lay eggs in N . tabacum, where eggs were continuously laid during the whole experiment period. However, eggs in P . vulgaris were hardly detected throughout the period. This study showed that the non-host plant, P . vulgaris, had a negative influence on the larval performance and adult oviposition of H . assulta, implying neonate stage is critical for larval survivorship, and ovipositional preference by the female is highly specialized to host plants. Further investigation is required to identify non-host factors, which could be applied to the development of alternative pest management strategy against H . assulta. [ABSTRACT FROM AUTHOR]