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Study on Fungi Associated with Elm Bark Beetles in Xinjiang

Author: ZhuXiaoMei
Tutor: LiuXueFeng
School: Northeast Forestry University
Course: Forest Protection
Keywords: Umbilical abdominal ( ? ) Insects Associated fungal classification New record Pathogenicity Test
CLC: S763.7
Type: Master's thesis
Year: 2011
Downloads: 45
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Abstract

Elm Xinjiang important green trees and tree species, with enormous ecological role to play in the wind and sand, to prevent soil erosion. In recent years, due to the hazards of the bark beetle caused great economic losses and ecological damage. Relative to the status quo of research on international understanding and governance of our small silverfish are still the majority stay in the pest itself, but the lack of understanding of the system, is bound to affect the governance measures and their effect on the forest pests. Through a series of studies to obtain a large number of fungi resources, found some new bark beetle associated bacteria taxa explore the the companion fungus in scolytids harm elm lethal process, pollution prevention and foster healthy elm for bark beetles landscape forest and ecological forests to provide basic information. In addition, in Xinjiang, although of U. pumila native tree species such as elm Dutch disease have a higher resistance, but from Europe and Central Asia in recent years, the introduction of a variety of Elm (round crown elm, European large leaves of elm, etc.), if the local bark beetles can carry elm the Dutch disease pathogens, it will increase the risk of intrusion and harm elm Dutch disease. Beginning in the spring of 2009, the Xinjiang umbilical abdominal scolytids of (Scolytus schevyrewi Semenov.) Serious regional small silverfish pest survey heavier woodland in the hazards of bark beetle hazard factor survey and acquisition victim-like specimens. Focus Bayingolin Mongolian Autonomous Prefecture and static, and Shuo Luntai and Korla City road protection forest belts small silverfish harm temporary sample survey. Four field trips point occurred elm trees withered and died. In addition, the pest of elm Dutch Disease pass epidemic umbilical abdominal piniperda growth potential weak woodland common. Survey of woodland have the basic small silverfish hazards, insect strain rate and high mortality rate, especially the more serious harm to the shelterbelt few natural regeneration elm bark beetles occurred in severe pest damage The woodland is often accompanied by other pests, frost damage occurred. U. pumila murdered like specimens were collected from 14 parts to complete the bark beetle associated fungi umbilical abdominal Purification and preliminary appraisal fungi were isolated 26 genera, including two types to be identified. Clear separation rate Fusarium widely distributed species, it is advantage in of U. pumila murdered site and adult, larval body surface and the larvae excretion average separation rate: 84.72%, 56.03%, 36.37% and 64.86%, respectively. Identified by morphological and molecular biology, isolated Fusarium Fusarium solani (F. solai). Collected the healthy the U. pumila specimens 11 copies, identified by cadres fungi were isolated and purified and identified fungi belonging to 15 genera, which to be identified category 1 species. The dominant fungi health U. pumila cadres fungi Tolura and Sphaeropsi, the average separation rate were 26.94% and 25.98%. In addition, collected in Fukang round crown elm bark beetle hazards, as well as the non-associated fungal isolates identified to the species of small bark beetles, fungi belonging to 15 genera were isolated, the type of which to be identified, there are two. The results show that the advantage widespread fungal Geosmithia, the white mycelium in the round crown the elm murdered site, trenches and other insects in the state of the surface of the average separation rate: 72.7%, 100%, and 88.54%, respectively. The isolated in the round crown elm on the scolytids trenches Geosmithia is a genus of filamentous fungi associated with a world wide distribution of food leather small silverfish typical. By which a bacteria morphological and molecular biological identification to determine the species: G. the pallid (G. Sm.) Kolarik Kubatova Pazoutova new record for mainland China. Also a Neoscytalidium the strains isolated, identified by morphological and molecular biology to determine the new record for China is a species: N. novaehollandiae Pavlic, Burgess, MJ Wingfield bacteria by bark beetles advantages associated umbilical abdominal solani Pathogenicity Test sickle Yin (Fusarium solani) field shows that its host plant U. pumila significant pathogenicity. The study results show that for the U. pumila endophytes, elm umbilical abdominal bark beetle associated bacteria and round crown the elm on unknown scolytids associated bacteria, regardless of the composition of the mycoflora dominant species of flora or fungi exist significantly different and showed correlation with bark beetles, which also provides basic information elm further prevention and control of pests and diseases. In addition, this experiment is not isolated elm Dutch disease pathogens the elm Shekou shell (Ophiostoma ulmi = Ceratocystis ulmi) and the the new elm Shekou shell (Ophiostoma novo-ulmi), which in a certain extent, also shows that the Xinjiang region elm was small silverfish serious harm, but the current study results did not find the Dutch disease.

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CLC: > Agricultural Sciences > Forestry > Forest Protection > Forest Pest and Disease Control > All kinds of tree pests and diseases and their prevention
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