What are the common diseases and insect pests in corn? How to prevent and cure it?

Corn is a kind of delicious food with rich nutritional value, it originated in Central and South America, and now it is planted all over the world. What are the common diseases and insect pests and control methods of planting corn?

1. Corn rust

Corn rust can be divided into two types in China, namely, common corn rust and southern corn rust, which mainly occur in South and Southwest China.

The main appearance of corn rust in the early stage is that light yellow long and ovate brown small purulent scars grow on both sides of the leaves, and then after the vesicles break, ferruginous powders appear, which is the pathogen summer spores; black oval or elongated bumps appear on the leaves of corn in the later stage. When it is cracked, it will reveal a dark brown winter robe.

Prevention and cure method

Select varieties with resistance to corn rust; strengthen field management, remove weeds in the field, reduce the invasion of pathogens; scientific management, appropriate fertilization and watering to improve the resistance of corn to the pathogen; the worst-hit areas can start spraying at the early stage of the disease, usually two or three times at intervals of about 8 days.

Second, corn leaf spot

Corn leaf spot is developed from a small leaf spot, which is water intrusive at the beginning, then turns bluish gray, severe prismatic spots can be about 20 centimeters long, and finally develops into brown dead spots, if you encounter Rain Water, the disease spot will grow black mildew.

Prevention and cure method

Select maize varieties with good, high yield and disease resistance, eliminate the disease source from the root, plant the field as far as possible, carry out deep winter irrigation to eliminate the disease source in the field, pay attention to the reasonable combination of chemical fertilizer, nitrogen and phosphorus, enhance the resistance of corn itself, and remove the weeds in the field as soon as possible to avoid infection.

Third, corn leaf spot

Leaf spot can occur from the seedling stage to the mature stage of maize, the spot is very small, the length is not more than 1 cm, but the number is very large, similar to oval, brown, dark in the middle, light around; the width is limited to between two leaf veins.

Prevention and cure method

Choose the right time to sow early so as to avoid the peak of the disease; keep sufficient base fertilizer and increase phosphorus and potassium fertilizer; several leaves at the bottom of corn can be removed properly to reduce the relative humidity in the field and make the plant grow stronger; Platycodon grandiflorum in the field is fermented at high temperature as compost.

There are many common diseases and pests in corn, but also very common, do not worry too much about these problems, we can query the relevant information, the use of scientific methods for prevention and control.