Potato Cultivation: Late blight disease destroys potato crop, know its symptoms and management

Potato Cultivation: About 40 to 45 percent of potato crops are lost due to pests, which include weeds, insects, and illnesses. This loss might be 100% at times. Timely management of late blight disease is essential for the successful production of potatoes. Phytophthora infestans is the fungus that causes this illness to spread. The potato late blight disease is very harmful. Due to this illness, the whole potato crop was destroyed, resulting in the devastating famine that struck Ireland in 1945.

The illness begins to spread from the plant’s leaves when there is less light and moisture in the air and rain or wet weather for many days.

Symptoms that are visible

In four to five days, this disease may wipe off all of the plant’s green leaves. The bottom surfaces of the leaves develop white balls that eventually become brown and black. Production declines, and potato tubers are smaller as a result of the leaf disease. 20 to 21°C is the ideal temperature for this. It is increased by humidity. Temperature and humidity are the two environmental variables that have the most effects on late blight development.

When the relative humidity is less than 90%, sporangia develop on the lower leaf surfaces and infected stems. The ideal range for the spore generation process, or sporulation, is 18–22°C (64–72°F); however, it may happen anywhere between 3 and 26°C (37–79°F). In order to cultivate potatoes and beans successfully, you must be aware of this illness, purchase the fungicide you’ll need for management beforehand, and apply it on time. Otherwise, you won’t have enough time to prepare once the disease strikes. The whole crop might be ruined in 4 to 5 days.

Controlling the late blight illness

A fungicide containing mancozeb may be sprayed at a rate of 0.2 percent, or two grams of medication dissolved in one liter of water, until the disease’s symptoms show up in the potato crop. However, mancozeb will not work if the illness symptoms start to show. Therefore, spray 3 grams of cymoxanil mancozeb medication, dissolved in 1 liter of water, on the areas where sickness symptoms have begun to show.

In a similar manner, 3 grams of Fenomedon mancozeb may be dissolved in 1 liter of water and sprayed. You may also dissolve 2.5 grams of metalaxyl and mancozeb combined medication in one liter of water and spray it. One acre will need 800–1000 liters of medication solution. Take precisely all of the directions on the package while spraying.