Identification And Pathogenicity Of Colletotrichum Species Associated With Anthracnose Disease Of Camellia Sinensis In Anhui Province

Tea plant(Camellia sinensis(L.)O.Kuntze)is of great important as an economic crop in China.The tea production in Anhui province has great potential occupying the third place in the national tea export volume.Tea leaves is an important resources of tea industry,which are often affected by the several diseases including pestalotiopsis theae sawada,neocapnodium theae hara,gloeosporium theae-sinensis miyake,exobasidium vexans massee,tea bud blight.These diseases may cause tea leaves to fall off and weaken tea tree growth when they are serious.Tea leaves play a crucial role in the export of agricultural products in Anhui province.Anthracnose disease has been a limited factor of sustainable development of tea industry in this region.In this study,diseased tea leaves showing symptoms of anthracnose were investigated and collected from four areas in Anhui province(Lujiang,Dongzhi,Qianshan and Xuancheng),and the causal agents were isolated by tissue separation method.Based on the observation of colony and conidia morphology,76 isolates associated with anthracnose were tentatively identified.PCR amplification was performed with specific primers of C.gloeosporioides complex species.The results showed that 75 isolates were identified as C.gloeosporioides complex species and one isolate was considered as non-C.gloeosporioides complex species.Phylogenetic analysis was further carried out to identify these isolates with six loci(ACT,CAL,CHS,GAPDH,ITS,TUB2),of which 41 isolates were identified as C.camelliae,33 isolates were identified as C.fructicola,one isolate was identified as C.siamense and one isolate was identified as C.karstii.Both C camelliae and C.fructicola were frequently isolated from the diseased leaves of tea plants in this study.Conidial suspension and mycelial agars were used to test the pathogenicity of Colletotrichum isolates on ’C.sinensis cv.Shuchazao’ by needling inoculation method.The results showed that the pathogenicity was different among the tested isolates on ’C.sinensis cv.Shuchazao’.Moreover,the pathogenicity of six representative strains was further tested on 21 different tea varieties/strains.The results showed that the pathogenicity was different on the same tea variety between the six strains,and the pathogenicity was also different on different tea varieties/strains for the same strain.The tea varieties ’C.sinensis cv.Echa 5’,’C.sinensis cv.Juhuachun’ and ’C.sinensis cv.Meizhan’ showed strong resistance against the tested strains.