Isolation,identification and latent infection characteristics of citrus anthracnose pathogens

【Objective】The present study aimed at species identification and latent infection characteristics of citrus anthracnose pathogens,providing scientific basis for prevention and control measures.【Method】Pathogen isolation, morphological characteristics observation and pathogenic test were performed using citrus samples collected from three areas in Hubei Province. Molecular identification by r DNA-ITS sequencing for representative strain(T4) was performed as well. Furthermore, the latent infection characteristics of anthracnose pathogens on citrus flowers and fruits were conducted by tissue isolation method.【Result】The results showed that 19 single-conidial isolates of Colletotrichum gloeosporioides were obtained,but they showed significant differences in pathogenicity. rDNA-ITS sequence of T4 showed 100% identity with that of C. gloeosporioides(Gen Bank accession No. FJ459917.1, FJ459916.1). The latent infection ofanthracnose pathogens on citrus flowers and fruits exhibited regularity:petal showing the highest carrying-rate in floral organs,pedicle and umbilicus exposing the highest carrying-rate in fruit, following by fruit stalk.【Conclusion】Anthracnose pathogens were found in flowers and fruits from all three researching areas, and they exhibited latent infection characteristics in citrus fruits. It is critical to control anthracnose pathogens at flowering stage and to disinfect fruit pedicle, umbilicus and stalk before storage.