First report of Colletotrichum queenslandicum and Colletotrichum endophyticum causing citrus anthracnose in Indonesia

Abstract

Citrus (Citrus spp.), including orange as an important one, has a high economic value and significant role both in global market as well as in Indonesia. However, citrus anthracnose caused by Colletotrichum spp. constantly becomes a limiting factor in citrus production. Nevertheless, there is no report on molecular basis about the species associates to the citrus anthracnose in Indonesia up to date. Therefore, this research aims to identify the isolates of Colletotrichum spp. based on polyphasic approach which combining morphological character, pathogenicity and multigene analysis using actin, β-tubulin, and GAPDH primers. Twenty-two isolates were obtained from leaves and citrus fruits with anthracnose symptoms which showed various morphological characteristics, both macroscopic and microscopic. Pathogenicity test results showed that all 22 isolates were virulent to Keprok Batu 55 orange and California lemon. The anthracnose symptoms produced are identical to the symptoms in the field, however the symptoms on the California lemon were milder than on the Keprok Batu 55 mandarin. The results of multigene analysis showed that there were three species causing citrus anthracnose in Indonesia, which were C. endophytichum, C. queenslandicum, and C. gloeosporioides. Those three species are C. gloeosporioides species complex, and this is the first report of C. endophytichum, C. queenslandicum causing citrus anthracnose in Indonesia which needs further concern for biosecurity. All isolate sequences based on actin, β-tubulin, and GAPDH gene markers were submitted into the GenBank and got accession numbers of OR188855–OR188875.