Identification And Biological Characteristics Of Tea Leaf Diseases In Shandong Province

Tea is one of the three largest non-alcoholic beverages in the world,wich in high health efficacy and economic value.Since the "Introduction Tea From South to North" was implemented in 1959 in Shandong Province,the number of the introduced species has been increasing and the planting area has been expanding,the tea plant diseases have gradually became a factor that can not be ignored in tea production.At present,there are few systematic studies on tea plant diseases in Shandong Province.Therefore,this experiment carried out disease investigation,identification of pathogen,biological characteristics of anthracnose,and evaluated the resistance of six main tea varieties to anthracnose in six main tea areas: Taian,Rizhao,Linyi,Qingdao,Weihai and Yantai of Shandong Province.Result could expected to provide a theoretical basis for the scientific prevention on control of tea leaf diseases and the healthy development of tea industry in Shandong Province.There were few kinds of tea leaf diseases in Shandong Province,mainly tea anthracnose(Gloeosporium theaesinensis),tea cloud leaf blight(Colletotrichum camelliae),tea rosette spot(Pestealotia theae Sawada)and tea bud blight(Phyllosticta gemmiphliae Chen et Hu),tea brown blight(Glomerella cingulata f.sp.camelliae and Botryosphaeria dothidea)is a newly discovered leaf disease,the anthracnose is the most widespread disease of tea trees in Shandong Province,which occurred in six main tea areas,tea moire leaf blight was more common in Rizhao Shenggushan and Qingdao Dongtai community tea garden,tea wheel spot disease occurres more seriously in leaves and old leaves in Junan County,Linyi,the disease also occurres in Rizhao Lanshan District and Donggang District,Tea bud blight was common in Taian Daiding Green Tea Garden in early spring and Qingdao Laoshan area,the local incidence of tea brown blight is found at District of Yushancha Farm in Rizhao Donggang.69 strains of anthracnose were isolated by tissue isolation,including 21 strains of Taian,8 strains of Rizhao,7 strains of Linyi,13 strains of Qingdao,11 strains of Weihai and 9 strains of Yantai.The taxonomic status of 69 strains was indentified by the method of morphological and molecular methed.The dominant fungi was Colletotrichum camellia,including 38 strains,2 of among them were Glomerella cingulata f.sp.camellia;16 strains were C.gloeosporioides;6 strains were C.fructicola;C.boninense included 5 strains;in addition,four strains were not identified to species,but according to the morphological characteristics,see them belong to Colletotrichum.Tea cloud leaf blight was caused by C.camelliae Massee.Tea wheel spot was caused by Pestalotiopsis theae.Tea bud blight was caused by Colletotrichum sp.Tea brown blight is caused by the compound infection of G.cingulata f.sp.camelliae and B.dothidea,it is the first report of tea leaf disease caused by B.dothidea.The most suitable carbon source medium for the growth of anthracnose was PSA.The yeast extract was best used in nitrogen source,the optimum p H is 6,it can grow at 5-40℃ and the optimum temperature is 27℃,12 h light and dark alternant was best for mycelial growth.A strong pathogenicity strain SNTC3 is screened from the pathogenicity test of pathogen identification and inoculated in leaves of 6 tea varieties in vitro,and the resistance of different tea varieties to anthrax is evaluated comparatively,the results showed that the resistance to anthracnose were the strongest in Zhongcha 108,the weakest in Anji white tea,and Fuding Dabai,Wu Niu Zao,Pingyang Terzao and Longjing43 belong to medium level.