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Studies on the Bio-ecological Characteristics of Seabuckthorn Carpenter Moth: Holcocerus Hippophaecolus (Lepidoptera: Cossidae)

Author: ZongShiXiang
Tutor: LuoYouQing
School: Beijing Forestry University
Course: Forest Protection
Keywords: Hippophae rhmnoidea Holcocerus hippophaeclus bio-ecological characteristics population dynamics niche sex pheromone
CLC: S763.7
Type: PhD thesis
Year: 2006
Downloads: 293
Quote: 10
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Abstract

China is a largest country in plantation area, germ plasm of natural resources of seabuckthorn in the whole world, and its distribution area is about 2 million hm2 and more than 90% of the world’s seabuckthorn resources. Seabuckthorn is not only the best potential and future used on a large scale to control desertification, to conserve land and water resources in Three North area , but also a significant biological resource of regional economic development and biological diversity for higher integrated exploitation and utilization values in China.However in recent years, the seabuckthorn carpenter moth Holcocerus hippophaeclus broken out in Inner Mongolia Autonomous region, Ningxia Hui Autonomous region, Shaanxi, Shanxi, Liaoning, Hebei and Gansu provinces, and caused a heavy ecological and economic loss.The related researches were very few for the infestation before it’s large scale occurrence .So, the author of this paper researched systemically the bio-ecology, damage characteristic, sex pheromone and its application technologies , and the main results showed as follows.1. The research results of biological characteristics indoor and outdoor showed that a generation of H. hippophaecolus lasted four years in Liaoning province, the mature larvae begin to pupate in the first of May under the ground and the moths emerge from the end of May to the early of September with two peaks of eclosion, the middle of June and the last of July respectively. The female moth always laid eggs to the crevice and wound in stem bark, the hatching rate of the egg is 90% and egg stage is 16d. The young larvae have the habit of aggregation with several to hundreds and transfer from the stems to the roots in current autumn. The mature larvae pupate in soil around the base of stem with the depth of 10 cm and pupal stage is 31d. The moth emergence occurs in 4:00-7:00 p.m., and copulation peak appears around 9:30 p.m.; the sex ratio of female to male is 1:0.85 in Inner Mongolia Autonomous region and 0.912:1 in Liaoning; the female may laid eggs through all day and night, especially in the next night between 8:30 to 10:00 p.m. after copulation; the longevity of male moth is 2-8 d and female moth is 3-8 d. The larva overwinter in the stems and roots of seabuckthorn, and the overwintering stages and location are not influenced by the direction of slope and the degree of damage in different woodlands.2. The spatial pattern of egg, larva and pupa are all the aggregated distribution by analysis with the traditional biostatistics and geo-statistics. The most ideal sampling method is the chessboard sampling.3. The values of developmental threshold temperature(C) and effective accumulative temperature (K) of the pupa are 12.056±0.176℃and 295.203±4.094 day-degree respectively under the condition of constant temperature, and under the congdition of variable temperature they are 15.481±0.419℃and 202.356±13.057 day-degree. However, the value of C and K of the egg under the condition of

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