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Study On Influence Of Pinus Massoniana Lamb.Damaged At Different Degrees On Population Quantity Of Dendrolimus Punctatus Walker

Posted on:2007-10-12Degree:MasterType:Thesis
Country:ChinaCandidate:H L LiFull Text:PDF
GTID:2143360185981332Subject:Forest protection
Abstract/Summary:PDF Full Text Request
Pine Caterpillar (Dendrolimus spp.) is the most important pest of forests in China. It damages 2 million ha of pine trees and causes economic loss of about 540 million RMB every year.Studying the influence of induced resistance produced by Pinus massoniana Lamb.damaged at different degrees and sprayed by different concentrations of methyl jasmonate on population quantity and the biological characters between black larvae and yellow larvae hatched from the same egg masses,which has very important theoretic and practical meaning on exerting adequately control disaster on natural and induced resistance of forests,developing effectively zoology regulate and control and deepening prediction techniques.The auther fed Dendrolimus punctatus Walker with pine needles damaged with different fashtions and different degrees to evaluate their effect on the growth and development of the pine caterpillar .The research results are as follow:1.After Dendrolimus punctatus Walker was fed with pine needles damaged at different degrees,amounts of food ingested, faeces excreted, weight of pupa, nutritional index, pupation, fecundity,: undamaged pines (0 defoliation) > seriously damaged pines (75% defoliation) > slightly damaged pines (25% defoliation) > moderately damaged pines (50% defoliation), except for the developmental period and mortality which exhibited opposite trend.2.After Dendrolimus punctatus Walker was fed with pine needles sprayed with different concentrations of methyl jasmonate (0mmol/l, 0.01mmol/l, 0.1mmol/l, 1mmol/l), the amount of food ingested, faeces excreted, weight of pupa, nutritional index, pupation, fecundity, developmental period and mortality manifest spraying 0mmol/l>0.01mmol/l>0.1mmol/l>1mmol/l, and the developmental period and mortality were contrary to others.3. According to the body color, there exist two kinds of Caterpillar larvae: black and...
Keywords/Search Tags:Pinus massoniana Lamb., Dendrolimus punctatus Walker, damage to different degrees, population quantity
PDF Full Text Request
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