Research Progress of Citrus Melanose

Citrus melanose consists of a series of plant diseases caused by the fungal species of the genus Diaporthe. It has been reported with over 30 Diaporthe species on citrus, including several important fungal pathogens, endophytes, saprophytes, and also latent fungal pathogens with an endophytic/saprophytic lifestyle. Among them, the disease symptoms caused by Diaporthe citri are complex, and the black spots and sand skin symptoms produced on fruits and leaves are the most serious harm to citrus. Currently, the primers and methods for the detection of D. citri have been constructed, and are supposed to be used in field monitor of the dynamics of the pathogen and the epidemiology of the caused diseases. In the orchard, the infection and outbreak of melanose is highly correlated to the orchard damage by natural disasters and continuous rainfalls, the main disease control strategy should be the combination method of agricultural control, physical control, and chemical control.For the agricultural control, the dead woods, twigs, and leaves should be cleared to reduce the formation of infection sources; for the physical control, it is important to avoid plant wounds by cold and sunburn, and the conidia spread by rains; for the chemical control, the usage of fungicides should be protective to the plant wounds, and also over the period of rainfalls. In addition, the research of the biological control of citrus melanose is still in its infancy, several studies have isolated different antagonistic microorganisms and tested their effects on the control of citrus melanose, which suggest their promising roles as supplementary fungicides. This review summarized the major research progresses of citrus melanose at home and abroad, and aimed to offer some insights to the control of the disease.