title: [Accumulation of lead in Spodoptera exigua (Hübner) and its impact on the population].
abstract: The heavy metals pollution is one of the ecological problems which have been paid close attention to Spodoptera exigua Hübner, one of the key pests on vegetables and cotton in the Yangtze River and its southern area in China, has broken out more frequently in recent years. In this study, accumulation of Pb2+ in S. exigua and its excretion were detected when fed with artificial diets with different Pb2+ concentrations (0.3, 1.2, 4.8, 19.2 and 76.8 mg x kg(-1), respectively). Life table was constructed according to the survival and growth of different stages of S. exigua. The effect of lead on three successive generations of beet armyworm was studied using the life table in the laboratory. It was found that the Pb2+ contents were significantly different when S. exigua was reared at different Pb2+ concentrations in the same generation in a significant dose-dependent manner. The concentration of Pb2+ increased with prolonging the stress time at the same time. The Pb2+ concentrations at the three developmental stages of beet armyworm followed the order of larvae > adult > pupa. The beet armyworm could excrete heavy metals by means of faeces, prepupa exuviate and puparium, and the concentrations of Pb2+ in faeces and prepupa exuviate were far higher than in puparium. According to the survival rates of different developmental stages, the female ratios and the egg numbers, the laboratory population life table was constructed. It showed that low doses of Pb2+ promoted the growth of the population, and high doses inhibited the growth, and the index of population trend (I) declined more rapidly with the increase of stress time. The study could provide references for long-term and objective assessment of heavy metal hazard and its effect on the populations of important agricultural pests.
authors.forename: Meng-Meng
authors.initials: MM
authors.lastname: Hu
authors.forename: Wen-Chen
authors.initials: WC
authors.lastname: Cai
authors.forename: Hong-Hua
authors.initials: HH
authors.lastname: Su
authors.forename: Yi-Zhong
authors.initials: YZ
authors.lastname: Yang
mesh_terms: D000818:Animals; D002681:China; D004032:Diet / Q000662:veterinary; D004785:Environmental Pollutants / Q000378:metabolism; D005260:Female; D007814:Larva; D007854:Lead / Q000378:metabolism*; D011679:Pupa; D018411:Spodoptera / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants; D007854:Lead