Purple blotch and Anthracnose disease fungal diseases have resulted in a 50 percent decrease of red onion crop in Badoc, Ilocos Norte, according to a Philippines media report.


Cornelio Dinong, municipal agricultural technologist said that fungal diseases in onions usually develop during drizzle and rainy season and has prompted farmers to grow other crops.

Purple Blotch is caused by the fungus Alternaria porri. It is an important disease in warm, humid onion-growing regions around the world.  The disease often begins on older leaves as small, sunken, water-soaked lesions with light centers. Lesions enlarge as disease progresses and turn purple to brown, often with yellow rings that create a distinctive bull’s-eye pattern.

The anthracnose disease of onion is responsible for severe leaf blighting in some fields. The lesions are bleached in color and may be seen along the length of the leaf, including the plant tissue near the bulb.