Comprehensive measures to prevent and control corn rust

Rust is one of the more common diseases on corn. It has a wide range of occurrence and has different degrees of damage to the normal growth of corn, which accelerates the drying of the corn plants, the grain is not full, and the yield is reduced. Lighter production reduced by 10%, and severe cases reduced by 30%. It mainly invades the corn leaves, and the heavy one also harms the corn leaf and leaf sheath. In the early stage of the disease, in the base and upper main veins of the leaves and on both sides, scattered or concentrated yellowish spots, the posterior protrusions form reddish-brown plaques, ie the pathogens of summer spores. Late lesions form black erythema, the pathogen teliospores. When corn rust occurs seriously, the leaves are covered with spores, causing a large number of leaves to dry up, losing photosynthesis, premature senescence of the plants, and imperfect grain, resulting in reduced yield. In the most serious case, the blade can be broken from the damaged part, and the whole plant is dry and reduced.
In North China, corn rust fungus teliospores were seen in the middle and late May, peaking in July, and the second peak in September; summer spores in mid-to-late June and peak in mid-August. From mid-June to mid-July, this month is the epidemic period of corn rust. The disease has sporadic morbidity since mid-July, and the spores are transmitted by airflow, repeated infection, and the end of August is the peak period. When the field is sick, it starts to expand downward from the top of the plant.
Incidence conditions of corn rust: high temperature is conducive to the survival, germination, spread and infection of the spores of the disease; soil and planting: low terrain, high planting density, poor ventilation and morbidity; fertilization: whether the disease occurs and whether the field is scientific Reasonable fertilization has a great relationship. The use of organic fertilizer, partial application or multiple application of nitrogen fertilizer is very serious.
Comprehensive prevention and control of corn rust First, select excellent hybrid corn varieties suitable for local cultivation. The varieties resistant to corn rust are the most economical and effective measures. Second, scientific fertilization: formula fertilization, increase phosphorus and potassium, and avoid micro-fertilizer. Partial application of nitrogen fertilizer or application of pure nitrogen fertilizer to improve the disease resistance of plants; Third, cultivation measures: appropriate early sowing, reasonable close planting, cultivating loose soil, pouring appropriate amount of water, creating an environment conducive to corn growth and development, and improving plant resistance Disease ability, reduce disease occurrence; Fourth, chemical control: the use of chemical agents to inhibit the germination and spread of spores, even if some plants occur, spraying the fungicide with the system of sucking crops, also has the role of killing bacteria and treatment.