Effects of Ageratina adenophora on the Growth and Adult Fecundity of Spodoptera Litura

Purpose To clarify the effects of Ageratina adenophora on the growth and fecundity of Spodoptera litura.

Method The study on the effect of host plant as the A. adenophora and Brassica rapa on the growth, fecundity and survival of S. litura were conducted in laboratory

Result S. litura can complete a whole generation fed with leaves of A. adenophora. But compared with the suitable host plant B. rapa, the growth rate of S. litura decreased, duration prolonged, weight loss, and survival rate, eclosion rate and fecundity decreased feeding on the leaves of A. adenophora. The larval and pupal duration of S. litura feeding on the leaves of the two host plants have significant difference (P<0.05), the larval duration ofS. litura was prolonged 10.26 days fed on A. adenophora. The weight of the 1^st to 6^th the instar larvae of S. litura feeding on A. adenophora were significantly decreased than those of the same instar of S. litura feeding on B. rapa, and pupal weight decreased by 15.79% (P<0.05) than feeding onB. rapa. The larval survival rate and eclosion rate of S. litura feeding on A. adenophora were 40.61% and 83.33%. It was decreased by 31.96% and 11.67% than feeding on B. rapa (P<0.05), respectively. Meanwhile, it caused a prolong for the oviposition duration of adultS. litura, significantly decreased the single female fecundity that feeding on A. adenophora, and decreased the sex ratio of S. litura population.

Conclusion Although the leaves of A. adenophora were not suitable for the growth and development of S. litura, the insect may eventually adapt to it as a host plant and completed a whole generation. So S. litura has the potential to become one kind of generalist enemy of A. adenophora.