Evaluation of Citrus Cultivars Susceptibility to Leaf Spot Disease Caused by Alternaria alternata under in vitro Conditions
نویسنده
چکیده
Alternaria brown spot is a serious disease of fruit and foliage of citrus. This disease caused by Alternaria alternata and causes serious economical losses on susceptible cultivars in Iran. In this research, susceptibility of seven citrus cultivars including Fortune, Orlando tangelo, Mineola tangelo, Page, Clementine, Sour orange and Sweet orange (Thomson) fruits to A. alternata was investigated. The result revealed that the Fortune, Orlando tangelo, Mineola tangelo, Page and Thomson fruits are highly susceptible and showed severe symptoms of brown spot, especially in “unwounded” fruits. In contrast, Clementine and Sour orange are resistant to this pathogen, and A. alternata could not grow on unwounded fruits. However, weak symptoms were observed in Clementine and Sour orange when cuticle was broken and flavedo or flavedo + albedo was removed.
منابع مشابه
Alternaria Pathosystems for Study of Citrus Diseases
Leaf spot disease of rough lemon and brown spot disease of tangerines caused by distinct pathotypes of Alternaria alternata, and postharvest fruit black rot disease caused by A. citri, are the three major fungal diseases of citrus. The pathogenicity and specificity for the pathogens of Alternaria leaf spot and brown spot diseases are associated with the production of different host-specific tox...
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