Prevention and control of corn bacterial wilt

Corn bacterial wilt is one of the main diseases in the middle and late stages of maize, and it is an invasive disease of the whole plant. From the end of maturity of corn to the stage of wax maturity, it is the peak period of the peak. Generally, the disease begins from the grouting to the milky stage, and the lower leaves gradually expand upwards, showing the symptoms of green blight, and finally the whole plant is obvious, which is easily distinguished from the healthy plants. Some strains have acute symptoms, that is, in the late stage of milk ripening or waxy stage, the whole plant is suddenly dying, and there is no obvious process of gradual development from the bottom up. This situation is especially common after rain. From the beginning of the disease to the whole plant, it usually takes about a week, and the short one takes only 1-3 days, and the long one lasts for more than 15 days. The base of the stem of the diseased plant becomes soft, and the interior is loose and easy to fold when exposed to wind. Some ears sag, the stalks become soft and are not easy to peel off. The leaves are also green and dry. The roots of the plants are obviously stunted, the roots are few and short, and they become black and rot. The stem was examined, the pulp was loose, the seed of the diseased ear was loose, easy to thresh, and the color was gray and dull.

Characteristics of the disease: The overwintering bacteria in the soil invaded from the roots after the sowing of the corn to the silking stage, and spread and spread in the plant. Corn is grouted to maturity in case of high temperature and high humidity, and the peak of incidence often occurs on sunny days after rain. There is a significant difference in disease resistance between varieties. Dwarf, early maturing varieties and double-eared corn have a serious incidence. The planting density is too large, and the nitrogen fertilizer is applied. The straw is not fermented as a fertilizer, and the pathogen is brought into the field, and the disease is heavy. Early onset is severe, and late onset is light. The plots with low ground and stagnant water are also seriously affected. Hail, insect pests, and trauma caused by various causes are conducive to disease development.

Control technology:

Breeding and planting varieties that are resistant to disease and disease.

Remove the sick body. After the corn is harvested, the residuals of the diseased plants are completely removed, burned intensively, and combined with deep lands.

Rotation. Seriously ill fields should be rotated for 2-3 years with other crops .

Sowing at the right time. Spring corn should be broadcast at a suitable time, which can effectively alleviate the occurrence of bacterial wilt.

Strengthen field management. Field management measures such as adding fertilizer, timely cultivating and eliminating stagnant water can promote the growth of maize plants and enhance disease resistance. Potassium fertilizer or nitrogen, phosphorus and potassium compound fertilizers are added during maize jointing or booting stage, and the disease prevention effect is better. .

Control pests and diseases. Timely control of corn borer and armyworm can reduce the occurrence of diseases.