Phytophthora infestans
Quick Summary
Phytophthora infestans is a water mold that causes late blight, a devastating disease affecting potato and tomato plants. This disease thrives in humid conditions with temperatures between 4 and 29 °C (40 and 80 °F), but is checked by hot, dry weather.1
Infected plants can rot within two weeks, exhibiting lesions on leaves, petioles, and stems. A whitish growth of spore-producing structures may appear on the undersides of leaves, and potato tubers can develop rot.1
The disease famously caused the Great Famine in Ireland in the mid-19th century due to a reliance on a limited variety of potato crops. Management strategies include using fungicides and developing resistant plant varieties, though eradication can be challenging due to the pathogen's ability to persist in the soil.12
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Great Famine…blight is the water mold Phytophthora infestans. The Irish famine was the worst to occur in Europe in the 19th century.
Read More…blight is the water mold Phytophthora infestans. The Irish famine was the worst to occur in Europe in the 19th century.
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plant diseaseNature and importance of plant diseases…(caused by the water mold Phytophthora infestans) that began in Europe in 1845 brought about the Great Famine that caused starvation, death, and mass migration of the Irish. Of Ireland’s population of more than eight million, approximately one million (about 12.5 percent) died of starvation or famine-related illness, and 1.5…
Read More…(caused by the water mold Phytophthora infestans) that began in Europe in 1845 brought about the Great Famine that caused starvation, death, and mass migration of the Irish. Of Ireland’s population of more than eight million, approximately one million (about 12.5 percent) died of starvation or famine-related illness, and 1.5…
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