Plant Pathology Science

Neofusicoccum mangiferae is the causal agent of branch wilt, blossom blight, canker and dieback on a variety of fruit trees such as almond, hazelnut, apricot, peach, citrus, grape and apple. Cracking and peeling of thin outer layer of bark and exposing black sooty mass of spores is a characteristic feature of disease. Pathogen causes gradual declining and sometimes complete death of trees. The fungus infects the hosts through wounds, created by pruning, frost damage, drought stress, or bark cracks caused by sunburn and develops under hot and sunny weather in summer. Good sanitation, fertilization of trees, adequate irrigation, appropriate pest control, preventing wounds, and avoiding unnecessary pruning are the methods for disease management.

Betasatellites, as begomovirus-dependent small circular single-stranded DNAs, are multifunctional agents that trigger disease symptoms, suppress gene silencing pathways and also interact with various cellular pathways and factors. These subviral elements have a conserved genome organization that encodes only a functional open reading frame on the complementary sense strand βC1. The encoded beta satellite protein affects only the helper begomovirus cycle factor. The small size with a strong promoter sequence and the ability to replace βC1 with foreign genes made beta satellites suspected tools for the investigation of functional genes. As we expand our knowledge of begomovirus / beta satellite complexes and their interactions with host plants, we develop management approaches for the expansion of begomoviral destructive diseases.