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Study Of Influencing On Growth And Development Of Dendrolimus Punctatus Tabulaeformis (Tsai Et Liu)

Posted on:2006-11-30Degree:MasterType:Thesis
Country:ChinaCandidate:L L ZhangFull Text:PDF
GTID:2133360152488511Subject:Forest protection
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Chinese pine caterpillai(Dendrolimus punctatus tabulaeformis) is the important insect pest feeding on pine needles in China, whose distribution is located in the south of Ningcheng city of the north Inner Mongolia, namely the wide area in the south of north latitude 42°, including Beijing, Hebei, Shaanxi, Shanxi, south of Gansu and Loess Plateau. And localized distribution at the hilly and high altitude area of Shandong, Hunan and Sichuan takes on style of island. Its host trees includes Pinus armandi, Pinus bungeana and Pinus massoniana besides Pinus tabulaeformis.In China study of biology, forecasting measures and management techniques about Chinese pine caterpillar has made great progress, however study on induced resistance, larva diapause and morph change of D. punctatus tabulaefoums feeding with different damaged Chinese pines has few literatures, these factors also have effect on population dynamics of D. punctatus tabulaeformis. This thesis focus on these factors, and the main study results as follows:1. By breeding Dendrolimus punctatus tabulaeformis using the needles from different state artificial-simulated of lost pine needles of Chinese pine, the results showed that Dendrolimus punctatus tabulaeformis fed with middling damaged pine needles is the least amount of food ingested, voided faeces, digestive coefficient and lightest weight, slower development, high mortality, lighest pupae. At the same time, it have direct ratio relation between pupae's weight and laying eggs amount, which lead to less laying eggs amount and lower fecundity, which also lead to quantitative decline on population of D. punctatus tabulaeformis. However these indexs ascend on condition of Chinese pine severity damaged. The nutritional indexes of larvae fed with 25% and 75% part damaged pine needles have no distinctly difference.2. The nutritional index of the dark morph was higher than that of the tint morph, however its mortality was lower than of the tint morph. But some nutritional indexesof the dark morph were lower than that of the tint morph among Chinese pine caterpillar fed with 50% part, damaged pine needles.3. By breeding D. punctatus tabulaeformis with the same egg mass at different density, the result showed that the body color cannot be distinguished until 2 instars. Additionally, with population density increasing, the dark morph larva quantity increases, and linetype relation is showed. The Supercooling point of tint morph is lower than dark morph. The cold-resistant of tint morph is stronger than dark morph. The larva fed with damaged pine needles is highter at supercooling point, but cold-resistant is of a sort.4. Exposure time of D. punctatus tabulaeformis at low temperature influence its survival rate. The lower temperature lead to lower survival time. And the survival rate of diapause larva is higher than non-diapause. The results showed that the cold-resistant of diapause larva is stronger than non-diapause at initial stages of exposure cold. The larva "take exercise" at lower temperature can heighten the survival rate of lower temperature.Water contents and supercooling points of dipause larvae of D. punctatus tabulaeformis is lower than non-diapause. The results showed that the cold-resistant of dipause larva is stronger than non-diapause. The chemical substance among diapause larva is higher than non-diapause as trehalose, protein,amino acid and fatty acid, is lower as free fatty acid and oxygen consumption. The dipause larva have higher nutritional substance, energy substance, lower oxygen consumption, lower supercooling points. This is likely to one main reason that the cold-resistant of dipause larva is stronger than non-diapause.
Keywords/Search Tags:induced resistance, Dendrolimus punctatus tabulaeformis, growth and development, color morph, diapause, low temperature
PDF Full Text Request
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