Biology, epidemiology

• Conservation, sources d'inoculum
  

Xanthomonas cucurbitae is easily preserved on the seeds of several Cucurbitaceae (pumpkins, summer and winter squash, zucchini, etc.) which ensure its conservation and dissemination. It is also found on infected plant debris which helps to sustain it in the soil and in the farm. Various Cucurbits and more or less affected weeds would allow it to be maintained in the environment of cultivated plants and could serve as sources of inoculum.

• Penetration, invasion

It probably occurs through stomata on leaves, it could be through lenticels on fruit, or from wounds or insect bites.

• Multiplication, dissemination

This bacterium multiplies rapidly on and in colonized tissues in which there are innumerable bacterial cells which will ensure secondary contamination. Sprinkler irrigation, wind and spray, rains, splashing, and the movement of people and machines in crops with wet vegetation ensure the spread of this bacterium.

The same is true for contaminated seeds which make it possible to sustain it from one year to the next on a farm if the seeds are collected from diseased fruits in particular.

• Conditions favorable to its development

It is favored by rainy periods, sprinkler irrigation, high relative humidity above 90%, and rather high temperatures, of the order of 25-30 ° C.

The parasitic pressure of this bacteriosis increases during the growing season and reaches a peak in late July and early August