Plant Diagnosis

Late Blight of potato and tomato Critical

Greasy lesions and rapid plant collapse caused by Phytophthora infestans during July–October

Description

Late blight, caused by the oomycete Phytophthora infestans, is one of the most devastating diseases of tomato and potato crops worldwide. It thrives in cool, moist conditions and spreads rapidly, infecting leaves, stems, fruits, and tubers. Symptoms begin as water-soaked lesions that quickly turn brown and necrotic, often accompanied by white fungal growth on leaf undersides. The disease can destroy entire fields within days under favorable conditions and is notorious for causing the Irish Potato Famine. Yield losses can reach 80–100% without intervention.

Symptoms

• Brown lesions with white mold, fruit/tuber rot.