How to Treat Sick Eggplants? A Detailed Guide to Common Disease Prevention and Control Methods
Eggplant is a nutritious vegetable loved by most people, but during the growing process it is very easily troubled by diseases. So, how do you treat a sick eggplant?
1. Eggplant brown spot disease
1. Symptoms of the disease
When seedlings are affected: brown sunken lesions appear at the base of the stem, densely covered with small black grains, and the seedlings damp off or wilt.
When leaves are affected: small round water-soaked spots first appear on the lower leaves, then expand into large spots with brown edges and grayish-white centers, bearing many small black dots in concentric rings.
When fruit is affected: dark brown oval sunken spots form on the surface, covered with small black dots arranged in concentric rings; when humid, the diseased fruit rots, drops off or dries out.
When stems are affected: water-soaked diamond-shaped sunken lesions appear, scattered with small black dots; later the epidermis splits open, exposing the xylem, making it easy to break; when the lesion encircles the stem, the plant dies.
2. Prevention and control methods
(1) Practice crop rotation; apply more organic fertilizer, potassium fertilizer and phosphorus fertilizer to strengthen the plants; drain promptly and maintain ventilation.
(2) After fruit set, spray 10% hexaconazole at 1500 times dilution; or 10% difenoconazole at 1500 times dilution; or 25% prochloraz emulsifiable concentrate at 800 times dilution, once every 5 days, for 2 to 3 consecutive times.
2. Eggplant gray mold
1. Symptoms of the disease
Infection at the seedling stage: the tips of the cotyledons die first, then it spreads to the young stem, which constricts and becomes thin, breaks and dies; when true leaves are infected, semicircular to nearly round light brown concentric-ring spots appear, and later gray mold grows and rot occurs on the leaves or stems.
Infection at the mature plant stage: large water-soaked spots first form along the leaf margins, then turn brown, forming nearly round to irregular or “V”-shaped pale yellow concentric-ring lesions densely covered with a gray mold layer; in severe cases the lesions merge, causing the whole leaf to dry up.
When stems and petioles are infected: brown lesions appear, and gray mold grows under high humidity. When fruit is infected: water-soaked brown lesions form locally around the stem end of young fruit, expanding into dark brown sunken rot, with irregular concentric-ring gray mold on the surface.
2. Prevention and control methods
(1) Choose eggplant varieties tolerant to low temperature and weak light; control temperature and humidity; plant on high ridges, with reasonable spacing, pay attention to ventilation, and drain after rain; apply more organic fertilizer, potassium fertilizer and phosphorus fertilizer to strengthen the plants; promptly remove diseased shoots and fruit and bury them deep or burn them.
(2) In the early stage of the disease, the following fungicides can be used: 50% iprodione wettable powder at 800 times dilution, or 25% azoxystrobin suspension concentrate at 1500 times dilution, or 40% pyrimethanil suspension concentrate at 1200 times dilution.
3. Eggplant leaf mold
1. Symptoms of the disease
When leaves are infected: chlorotic spots with indistinct edges appear, and grayish-green mold grows on the underside of the lesions, causing the leaves to drop early.
When fruit is infected: the affected part turns black and leathery, mostly spreading downward from the fruit stalk; white patches appear on the fruit, and mature fruit develops yellow, sunken lesions that gradually turn black and finally become mummified fruit.
2. Prevention and control methods
(1) Choose disease-resistant varieties; practice crop rotation; plant at reasonable spacing and pay attention to ventilation and drainage.
(2) In the early stage of the disease, the following fungicides can be used: 25% tebuconazole at 1500 times dilution, or 47% kasugamycin·copper oxychloride wettable powder at 800 times dilution as a spray. In greenhouses, 45% chlorothalonil smoke agent at 250g per mu can be used with the greenhouse closed for fumigation.
The common diseases of eggplant are the three above; doing good prevention work is the key to eliminating eggplant diseases.