What to Do About Nutrient Deficiencies in Corn? Common Symptoms and Control Methods

Corn is a common crop and the main source of net economic income for many farming households. During growth, corn, like humans and other animals and plants, needs multiple elements to grow healthily. If a certain element is lacking during planting, it will not only affect the growth of corn, but also affect yield and quality, reducing economic returns. Below, Qinnong Web brings you the common nutrient deficiency symptoms of corn and their control methods.

1. Phosphorus deficiency

When corn is deficient in phosphorus, growth is slow at the seedling stage, and the leaf tips and leaf margins turn purplish red. This is the most obvious feature. The leaf edges curl, the leaf color is green or grayish green, and the stalks are thin and weak. As the plant grows, the purplish red at the leaf tips gradually disappears, and the lower half of the leaves turns yellow. Some hybrid varieties do not show purplish red at the leaf tips and margins during the seedling stage, but phosphorus-deficient seedlings are definitely shorter than normal seedlings. Phosphorus deficiency also affects later pollination and grain filling in corn, and after maturity the corn has many shriveled kernels, affecting yield and quality.

Control methods: For soil with low phosphorus content, increase the application of farmyard manure or phosphate fertilizer to increase phosphorus content and prevent phosphorus deficiency. If corn is deficient in phosphorus at the seedling stage, phosphate fertilizer can be added. If it is caused by long-term poor conditions, adding phosphate fertilizer alone cannot directly restore it, so a combination of foliar fertilizer spraying and additional phosphate fertilizer application can be used.

2. Nitrogen deficiency

During the corn growing period, the demand for nitrogen is relatively large, so nitrogen deficiency is also a relatively common phenomenon. When nitrogen is deficient at the seedling stage, growth is slow and plants are short, with yellow-green leaves. As time goes on, yellowing starts from the older leaves in the lower part of the plant and gradually moves upward. When the entire leaf has turned yellow, the leaf sheath turns red, and the leaves finally turn yellow-brown and die. When nitrogen is deficient in the later growth stage, tasseling is delayed, the ear cannot grow normally, and yield is reduced.

Control methods: Apply sufficient base fertilizer. When planting, fertilize in combination with plowing. It is best to choose a mixed application of farmyard manure and chemical fertilizer. Apply nitrogen fertilizer at the seedling stage and tasseling stage. The amount of topdressing depends on the growth condition of the plants. When nitrogen deficiency is found, a low-concentration urea aqueous solution can be sprayed.

3. Potassium deficiency

When corn is deficient in potassium, the color of new leaves is yellow or yellow-green, planting and growth are slow, stem nodes are shortened, stress resistance and disease resistance are weakened, and it is susceptible to pests and diseases. Some old leaves begin to yellow at night, and the leaf margins become scorched. This scorching develops along the leaf veins, and in the end the area around the leaf veins all becomes brown stripes. In addition, when corn matures, potassium-deficient plants are very prone to lodging.

Control methods: For potassium deficiency, potassium sulfate, potassium chloride, or potassium-containing compound fertilizer can be added to the base fertilizer before sowing, generally applying more than ten kg per mu. If potassium deficiency occurs later, potassium fertilizer can be applied as topdressing.

4. Zinc deficiency

Zinc deficiency in corn is very easy to identify. Its notable feature is the growth of white buds. The leaves begin to lose green color, the leaf tips and leaf margins turn yellow, and there are also stripes around the leaf veins, but they are yellow-white. Long-term zinc deficiency causes the leaves to dry up and die, and at tasseling the ear is smaller, with missing kernels and bald tips.

Control methods: Likewise, add an appropriate amount of zinc fertilizer to the base fertilizer, generally applying one or two kg of zinc sulfate per mu. If zinc deficiency occurs during later growth, zinc sulfate can be mixed with water to make a low-concentration solution for foliar spraying, with excellent results.

The above are the common nutrient deficiency symptoms of corn and their control methods brought to you by Qinnong Web. We hope they can help you. To learn more about corn cultivation knowledge, please stay tuned to Qinnong Web.