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Aromatic camphor (Cinnamomum camphora var. Linaloolifera Fujita) is the camphor five natural type foliage with a aromatic camphor alcohol (content 23-98%), and is China's major timber species and economic trees, is also a major environmental trees and landscape trees and shrubs. Natural aromatic camphor resources are extremely scarce, so the development of the aromatic camphor is the main source of aromatic alcohols, artificial planting. Mingxi County survey found that aromatic camphor anthrax in seedlings and young growth in general and severely occurred, causing great economic losses, has become a major obstacle to artificial planting the development of aromatic camphor. Due to lack of understanding of the disease occurrence characteristics and during the development of our province, and also a lack of a system study of the disease at home and abroad, To this end, the paper of the pathogen identification and biological characteristics of the diseases, the incidence of disease, the law of development , the space distribution of diseased plants, comprehensive prevention and treatment of diseases of the four aspects of the study, the results are as follows: 1. aromatic Xiangzhang anthrax symptoms 1-2 years seedlings gradually withered to base more from top shoot from serious death of the whole plant . Lesion occurred in the tip, leaf margin, first as a dark brown small point, after expanding into the brown spots on sometimes obvious Physalospora appears on the lesion, some lesion at an annular off some lesions on several a fusion of irregular shape. Were round or oval lesions on the young branches, expansion into streaks or circumcision, early purple, brown, black gradient brown lesion link after fusion, if around the branches circle, the branches the upper black dry heavy diseased lesion along the backbone down the spread of whole dead last. 2. Pathogen identification and biological characteristics through morphological identification of of aromatic camphor anthrax bacteria, to determine if the pathogen the Colletotrichum gloeosporioides Colletotrichum gloeosporioides (Penz.) Sacc.] Mycelial growth on PDA medium best; growth can be within the range of 10-35 ℃ temperature and pH 4-12, the optimum temperature of 25 ° C. The optimum pH value of 6; the sporulation's temperature range for 15-35 ℃, the best sporulation temperature of 30 ° C can be within the range of pH values ??of 5-12 sporulation, sporulation optimum pH value of 12; optimum temperature for spore germination is 25 ° C, the optimal pH 5 conidia in the humidity of more than 95% have a high germination rate; continuous light most favorable to the mycelial growth and spore germination, dark conditions most conducive to the formation of spores; carbon source utilization, potato, The starch is most conducive to the mycelial growth and spore formation, the use of a nitrogen source, peptone most conducive to the mycelial growth and spore formation, C source can promote mycelial growth, N sources can promote the formation of spores. Diseases during the development of research results show that the disease is the disease of a high temperature and humidity. The disease pathogens wintering mycelium the deciduous or residue on the tree leaves tissues. Wintering pathogen conidia spread diffusion in May of the following year, the main route of transmission is the wind and rain spread; peak incidence is generally in the 7-9 month November disease to stop the development. Different site conditions, forest canopy, the age of the occurrence of disease development significantly affect: uphill stand, stand edge aromatic camphor incidence of heavy, heavy canopy lower susceptibility, the heaviest incidence of 1-year-old seedlings. Diseased space distribution pattern determined by the aggregation index a regression of 1wao and Taylor's power law model analysis, results consistently show: of aromatic camphor Anthrax diseased plants in the forest, space distribution type aggregated distribution. 5. Comprehensive prevention and control of diseases in indoor efficacy test fungicides on mycelial growth test results show the inhibitory effect tuzet strongest average inhibition rate of 90.50%; worst Bordeaux mixture, as 22.70%. 8 fungicides virulence size based on virulence regression equation and EC50 results as follows: the tuzet gt; carbon grams gt; chlorothalonil gt; mancozeb gt; behalf of Sen zinc gt; thiophanate gt ; carbendazim gt; Bordeaux mixture. The field efficacy determination, the best spraying effect tuzet average control effect reached 83.83 percent, the worst mancozeb, average control effect was 43.87%. Silvicultural measures to prevent the test, the best control effect of impurity control effect reached 73.02%. Followed by thinning, control effect was 55.22%, in the actual prevention should be mainly to purify a comprehensive prevention and treatment, supplemented by several other silvicultural measures.
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