Alternaria brown spot of citrus: the risk and management strategy

Abstract: Citrus Alternaria brown spot(ABS),caused by Alternaria alternata pathotype tangerine,is a major problem on some tangerines,hybrids of tangerine and grapefruit or tangerine and orange,as well as grapefruit. It causes defoliation,twig dieback,young fruit-dropping,and dramatically market value reduction of infected fruits,especially on susceptible citrus varieties. Considering the high risk of ABS to Chinese citrus industry and the knowledge limitation to this disease in China,we reviewed the occurrence status and research progresses of ABS based on the related literatures,analyzed the potential risks and proposed the management strategy. Through this effort,we are expecting to enhance the awareness of citrus industry relevant administrative sectors,R & D and extension experts,as well as citrus-growers to ABS,thus the stakeholders could take the preventive measures before its epidemic.