Investigation And Risk Assessment Of Forestry Pests In Chaoan District In Chaozhou City

In recent years,the overall trend of occurrence and dispersal of forest pests have increased significantly.This increase has directly affected the sustainable development of forest economy and seriously threatened forest resources as well as ecological security.In order to investigate the occurrence of forest pests in C haoan area,it is necessary to find out the types and distribution of different pests.The distribution,occurrence and harnesses of various forest pests especially after 2003 were used to correctly predict the occurrence of forestry pests and their development trends.A comprehensive large-scale investigation was carried to provide the theoretical basis for scientific prevention and control of forestry pests in C haoan.After detail systematic investigation and idenfication of forest pests in C haoan,157 species of forest pests were found.Among them,there we re 128 species of forest insects,20 species of forest diseases and 9 species of harmful plants.Among the 157 different forest pests,three forest quarantine pests(Heterobostrychus aequalis,hibiscus mongolicum,and Mikania micrantha),1.91% of C haoan forestry pests;national forestry risk 10 species of pests,accounting for 6.37% of pests in C haoan,of which 3 species of pests(Euphorbia pulcherrima,Leptocybe invasa,Cyrtotrachelus longimanus),disease 4(bamboo witches broom,Eucalyptus bacterial wilt,Citrus huanglongbing,Xanthomonas Campestris),harmful plants 3(Cassytha filiformis,Cuscuta chinensis,Ipomoea cairica).As Mikania micrantha and Eucalyptus bacterial wilt have caused serious losses in Chaoan District,a comprehensive risk assessment analysis was carried out.The risk index was R=1.56 and R=2.06,respectively.According to the risk assessment criteria,Mikania micrantha belonged to moderate risk pests,and Eucalyptus bacterial wilt was highly hazardous pest in C haoan.