Xanthomonas cucurbitae 

(from Bryan 1926) Vauterin et al. 1995

Bacterial spots

- classification : Bacteria, Proteobacteria, Gammaproteobacteria, Xanthomonadales, Xanthomonadaceae
- synonyme : Xanthomonas campestris pv. cucurbitae  (Bryan) Dye (Sadder & Bradbury 2005)

- English name: bacterial spot, bacterial Leaf spot

This bacterium is widely distributed in the world; it mainly affects various Cucurbits (watermelon, melon, cucumber, butternut squash…), but its damage is particularly damaging on squash and pumpkins.

It is reported in particular in Asia (India, China, Japan, etc.), rather locally in Africa, Australia, Europe (Italy, France, etc.), America (USA, Argentina, Brazil, Uruguay, etc.), Australia, and New Zealand. It is on the rise in the United States (where it was first described in 1926), in the Midwest, where 40 to 50% of the plots on which squash are produced are affected, with 3 up to 94% of pumpkins showing symptoms.

It is sometimes severely rife in France mainly on squash, both in the South-West and the South-East. The damage observed is sometimes significant, especially during the conservation phase; sometimes a high proportion of the fruit can rot during this phase. It has been reported in Réunion.

In many countries, this bacteriosis manifests itself both during vegetation and during fruit storage. The percentage of affected fruits can sometimes reach more than 50%, causing significant economic losses.