Species identification of Colletotrichum the causal agent of strawberry anthracnose and their effects on fruit quality and yield losses

摘要

This study was conducted during the period from 2010 to 2012 and focused on strawberry anthracnose associated with diseased strawberry plants which caused root rot fruit and yield losses by Colletotrichum spp. Two local species of Colletotrichum fungus were identified based on the morphological, pathological characteristics and PCR analyses using specific primers. The first species was identified as Colletotrichum gloeosporioides [teleomorph Glomerella cingulata], and the second was identified as C. acutatum [teleomorph Glomerella acutata]. Pathogenicity was tested and confirmed by artificial inoculation of four strawberry cvs. i.e. Festival, Sweet Charlie, Tamar and Yael. Both two local species were found to be pathogenic for both tested strawberry cultivars and all inoculated parts showed typical symptoms of anthracnose. Tamar cv, was the most susceptible than Yael cv. Also, data indicated that, C. gloeosporioides was more virulence than C. acutatum in pots grown under greenhouse conditions. Fruits of three cultivars i.e. Sweet Charlie, Tamar and Yael were tested for their susceptibility to Colletotrichum acutatum and C. gloeosporioides. Results indicated that, both species were found to be pathogenic to all tested strawberry fruit cultivars. Yael cv, was the most susceptible than Tamar fruits. and C. gloeosporioides was more virulent than C. acutatum. The former data led to dramatic changes of all morphological, physical and bio-chemical properties in addition to some mineral contents of inoculated fruits compared with non-inoculated ones. This is the first report, relying on accurate molecular identification (PCR), of the two major Colletotrichum species isolated from strawberry plants in Egypt.