Study On Leptispa Longipennis (Gestro)

Leptispa longipennis (Gestro), a species of beetle, belongs to the Coleoptera, Hispidae, Callispinae, Leptispini, Leptispa Baly. The pest mostly distributed in Guangdong province and Guangxi Zhuang Autonomous Region in China, also recorded in Bhutan and Burma. Its main host plants are the bamboos. The research mainly studied its morphological, biological and ecological characteristics by a systemic investigation and observation to grope for the phylogeny and provided advisable directions for the pest population prevention and forecast. Meanwhile, different pesticidal approaches were implemented to sieve some effective control methods. Also combined with the forestry management measures to aim at the purpose of integrated pest control.1 The biological characteristics of L. longipennis (Gestro)Being investigated, there are 6 host plants of bamboo for the beetle. They are Lingnania cerosissima (McCl.) McCl., Melocanna baccifera (Roxb.) Kurz, Sinocalamus latiflorus (Munro) McCl., Dendrocalamopsis oldhami (Munro) Keng f., D. beecheyana (Munro) Keng f. and D. beecheyana var. pubescens (P.F.Li) Keng f. The most serious damaged bamboo was D. oldhami, and then were D. beecheyana and D. beecheyana var. pubescens. The third was Sinocalamus latiflorus. The beetle rarely damaged Lingnania cerosissima and Melocanna baccifera.The beetle happened 1 generation in 1 year in Yongding county, Fujian province. The fascicular bamboos were mainly damaged by adult. The adult entered to overwinter in the bamboo in the last ten days of November. In the middle ten days of March in the coming year, the adults terminated dormancy and copulated frequently and repetitively. At the beginning of April, the female laid eggs. Its laying season would last for about 2 months. The egg stage could last for about 8-14 days. The 1st instars larva would be hatched out in the middle ten days of April. The larva had 3 instars, the 1st would last for 5-7 days, the 2nd would last for 6-9 days, the 3rd would last for 11-16 days. The 3rd instars larva began to pupate in the middle ten days of May. The pupa stage could last for 8-9 days. The emergence of adult started to occur in the last ten days of May and would last to the first ten days of July, and then went into a stage of rampantly damaged to the bamboos. The adults could mate multi-time each other in all life except the dormancy. During the laying season, the female adults usually laid eggs in many times, and each time a female could produce 1-15 eggs or more. A female's maximum laying was 152, the minimum laying was only 20, and the mean laying was 64. The adult could live to the first ten days of July. The life-span of females were 330-408 days, and the males' life-span were 316-400 days. In the average life-span, the females' were fortnight more long than the males'.2 The spatial pattern and vertical distribution of L. longipennis (Gestro)Measured by aggregation indexes method, Iwao's model, Xu Ru-mei's model and Taylor's power law, the results indicated that the spatial pattern of population was conferred to assemble distribution in the fascicular bamboo forest, and which basic distribution components were colonies. The individuals were...