Corn Leaf Spot Disease Pictures and Treatment Methods

AbstractAgricultural control: remove diseased leaves from the lower part of diseased plants, and pay attention to drainage in low-lying plots. Timely fertilization: apply 10-20 kg of chemical fertilizer from the jointing stage to the tasseling stage of corn. Chemical control: use 15 g of 30% hexaconazole suspension concentrate, 30 g of 10% Bacillus subtilis, and 50% carbendazim wettable powder 500-600 times liquid for control. Increase phosphorus and potassium fertilizer: spray potassium dihydrogen phosphate.

1. Agricultural Control

1. Corn southern leaf blight, northern leaf blight and gray leaf spot are the main diseases in corn production, generally referred to as leaf spot disease. They often occur together, with a moderate degree of occurrence, mainly damaging leaves and husks. The lesions are irregular and translucent, grayish-white in the center with brown edges, and bear small black dots, namely the ascostromata of the pathogen, mainly distributed in Jilin, Liaoning and Henan and other provinces.

2. If there is more rain this year, fertilizer damage will occur slightly more severely than in previous years, so it is necessary to actively carry out the prevention and control of corn leaf spot disease, which is helpful for improving the yield and quality of corn.

3. During this period, diseased leaves on the lower part of diseased plants need to be removed in time to strengthen the mid-to-late stage management of corn fields. Cultivation and weeding can be carried out, and low-lying plots need attention to drainage, which is helpful for improving the microclimate environment of corn fields and enhancing the disease resistance of plants.

2. Timely Fertilization

From the jointing stage to the tasseling stage of corn, 10-20 kg of chemical fertilizer can be appropriately applied as a topdressing, which is helpful for improving the resistance of varieties, so as to control and reduce the harm of corn southern and northern leaf blight.

3. Chemical Control

1. Corn leaf spot disease needs to be prevented as early as possible, with key prevention for susceptible varieties and fields with disease in previous years. Usually, once scattered diseased plants are found in corn planting fields, chemical control is needed to control the disease center and reduce the spread of the pathogen.

2. In the early stage of the disease, chemical control can be adopted in time. During this period, per mu, use 15 g of 30% hexaconazole suspension concentrate, 30 g of 10% Bacillus subtilis, 50% carbendazim wettable powder 500-600 times liquid, 75% chlorothalonil wettable powder 600-800 times liquid, 65% zineb wettable powder 400-500 times liquid, as well as thiophanate-methyl (Topsin-M), propiconazole, difenoconazole (Score) and other agents, diluted with water for spraying.

3. Generally, spray once every 7-10 days, and continuous control 2-3 times is sufficient. Spraying can be chosen on sunny days, and after application, ensure no rain for more than 5 hours for it to take effect.

4. Increase Phosphorus and Potassium Fertilizer

1. Generally, for corn plots with phosphorus deficiency symptoms, an appropriate amount of potassium dihydrogen phosphate can be sprayed to supplement trace elements, which is helpful for improving corn resistance.

2. For severely affected plots, after the condition is controlled, potassium dihydrogen phosphate or other foliar fertilizers can also be sprayed to promote the rapid recovery of corn growth, so as to improve the yield and quality of corn.