[1] Specifically, certain lemon, lime, orange, mandarin and grapefruit species are susceptible hosts for this pathogen.

[2][3] The host is more susceptible to disease in climates with dry, warm summers and cool, moist winters.

Alternaria alternata's conidia disperse via air currents, and their release from the lesions can be triggered by rainfall, or even just a sudden increase in humidity.

Because fungicides have proved to be unhelpful in stopping the infection of citrus fruits, the use of resistant plants have proven to be the most advantageous form of management.

[8] Alternaria citri can be found worldwide, in areas that store and produce citrus.

[6] A common management practice is to let the infected fruits drop prematurely in order to prevent contamination of the healthy crop.

[12] No external symptoms or signs are visible when the fruit is still attached at the stalk end during development and is completely intact without any disruption to the peel.

This occurs because the fruits become detached from the stalk end, providing an exit route for the infection to spread to the peel that it is no longer intact.

EndoPG is an endogenous polygalacturonase, which is a cell wall degrading enzyme that helps the pathogen take over the plant's nutrient source.

A. citri that lack the ability to produce endoPG due to mutation have limited success because they are unable to penetrate through the cell wall.