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Study on Canopy Arthropod Community Structure and Dynamics in Chestnut Orchard, and Bionomics of Chestnut Gall Wasp (Dryocosmus Kuriphilus Yasumatsu)

Author: RenShuang
Tutor: DengXinPing；ZhaoZhiMo
School: Southwest Agricultural University
Course: Agricultural Entomology and Pest Control
Keywords: Chestnut Canopy Arthropod Community Structure and dynamics Time Niche Chestnut gall wasp
CLC: S436.64
Type: Master's thesis
Year: 2003
Downloads: 127
Quote: 2
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Abstract

This study looks at the governance of Chongqing chestnut production and pest status quo, investigation and laboratory study of forest systems combining research means, integrated use of the principles and methods of community ecology, two growing seasons in 2001-2002 chestnut canopy arthropod community structure characteristics, the time pattern of the dominant pests and natural enemies of forest dynamics and biology ecological learning chestnut gall wasp, forest growth and decline of the impact factor has been studied. The main contents and results are summarized as follows: 1, composed of community structure and the various types of group relative abundance in 2001 and from February to November 2002, a systematic survey, a random survey combined indoor rearing methods arthropods 136 kinds were obtained under the 12 orders, 63 families, including vermin 70 kinds, 62 kinds of natural enemies and neutral insects, respectively, accounting for 51.47% of the total number of species, 45.59% and 2.94%. Predatory enemies natural enemies in 47 species of parasitoid in 15 species, respectively, accounted for 75.81% and 24.19% of the number of species of natural enemies of the pest species number is slightly more than the number of natural enemy species PREDATORY significantly more than the number of species in the natural enemies of the parasitoid in species number. Order to further analyze the community structure, the chestnut canopy arthropod community is divided into three trophic levels, four functional groups, and 11 taxa, relative abundance analysis showed that herbivorous trophic levels in a number of species and the number of individuals in both absolute advantage, mainly sucking functional groups, especially aphids taxa quantity. Chestnut storage period pests bore fruit pests peach punctiferalis largest number. Community survey on the basis of clear chestnut crown of arthropods and the proposed Chestnut arthropods directory. 2, the chestnut canopy arthropod community seasonal dynamics 2.1, the general community, community groups, major pests and natural enemies individuals Quantity season dynamically through the designated regular surveys to study the dominant groups, the seasonal dynamics of major pests and their natural enemies in the number of individuals. The total number of individuals arthropod community, and Homoptera insects curve are the two peaks, two peaks appear in late April and mid-September, the first peak was significantly higher than that of the second peak, the formation of these two peaks the dominant species number are spotted winged aphids; Coleoptera insects also showed a bimodal curve, two peaks in mid-May and early September, and the first peak> second peak; Lepidoptera insects appears a peak period occurred only in the mid and late July. The incidence of major pests obvious stages. Spot-winged aphid population dynamic performance of the spring peak type and fall peak type; weevil number more in early April and early September; scarab increased sharply during early April to late May, in mid-May Quantity peaked; larger number of Lepidoptera larvae occurred from June to August, peaking in mid-July. Erigonidium graminicola natural enemies in early April to late-May a large number of quantitative curve has two peaks, respectively, in mid-April and early May, and subsequently the curve presents serrated; Harmonia axyridis number two distinct peak in early April and May respectively on the mid-curve is also presented in early July after the number of zigzag trend. 2.2 community in the development of the various stages of the determination of the dominant species of pests and their natural enemies, and community structure analysis 2.2.1 dominance analysis and determine the dominant species communities dominant species differ in the various stages of the development of communities. Very prominent spot-winged aphids in early April to early May advantages, Abstract 5) j copies scarab dominance over the spotted winged aphids, beetles May to late June early chestnut aphid worry about potential degree more than ten, from June mid-to early September, like A, Li big aphids, caterpillars, turn up the spot winged aphids dominance spot winged aphids in mid-September to late to worry about potential species again. In early April to early July, the natural enemies of the dominant species Erigonidium graminicola, mid-July to late September, worry about the potential large grass maggots degrees higher species, Harmonia axyridis, brown Clubiona, twelve spot clever ladybug, Harmonia axyridis. 2.2.2 The species richness, community structure characteristics, diverse offerings, community structure characteristic index of evenness and ecological concentration index analysis of the total community, pest sub-community and natural enemy sub quantitative characteristics of community structure in time. Analysis showed that the chestnut growth period and weather impact mainly due to changes in community structure characteristics, pest sub-community structure characteristic index variation in time is consistent with the general community, the number of changes in pest sub-community determines the total number of community structure characteristics change law. The 2.3 community seasonal pattern and Chestnut pests comprehensive lift the optimal management strategy using sequential sample split the community is divided into three stages, and combined with the climatic conditions and chestnut growth period the various stages of the pest management strategy. The early stages of community development for the spring and early summer chestnut sprout leaf expansion the r-countermeasures pests spots winged aphids in the number of dominant communities built in the early state in a variety of pests and natural enemies. This stage should be closely monitoring the development of pests and natural enemies, pick governance of individual insects plants, avoid large areas of pesticide application: community development peak in early summer - summer - early autumn chestnut tree flowering - fruit - growth - fruit ripening stage, the occurrence of major pests and damage has obvious stages, the natural enemy populations is insufficient to control pests rampant, but the pest population is under the joint control of the role of environmental conditions and natural enemies in the forest with a relative balance status. This stage is the period of chestnut large numbers of various pests and The major pests formation rampant harm, should seize the Phases of insect pests, prevention and treatment for one or two various population densities and the upswing major pests, while fully natural play natural enemies to control role; gradual recession of the third stage in the late summer fruit harvest stage community, the spotted winged aphids are the dominant species in this stage, the number rose to dominance and ecological community in elevated concentration The diversity and evenness decreased gradually into the dormant period at this stage after the chestnut harvest, should pay attention to clean up the pastoral and timely processing of pest overwintering sites. 3 the time major pests and predators niche determination Chestnut Canopy Arthropod Community pests and natural enemies niche. Application niche concept analysis of a number of characteristics of each group occurred, the utilization of a variety of pests and natural enemies of environmental resources, to explore competition and coexistence mechanisms between pests and their natural enemies. Results?

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