Corn virus disease prevention and control technology

In recent years, the area of ​​corn virus disease has expanded significantly, and some fields have been seriously damaged, which has serious impact on production. Corn virus disease has dwarf mosaic disease and rough disease, mainly corn dwarf mosaic disease. The disease is transmitted by the poisoning vector insects, aphids, thrips and gray planthoppers. Once the corn is infected, there is no cure for it. The corn varieties used in the current production are basically not resistant to viral diseases, and the comprehensive control is mainly carried out by controlling the transmission of the drug through the "control of pests and diseases". Since the pre-transmission vector locusts are more serious than in previous years, this year's corn virus disease has a potential threat of epidemics.

 

Symptoms and regularity

 

After the corn is susceptible, the seedlings of the new leaves first produce round chlorotic spots, which gradually spread to the whole leaf and appear as mosaics. Usually, the corn plants are dwarfed, and the plants that are seriously ill can not be sturdy and strong, and the plants are prematurely dying. Maize can be infected during the whole growth period . It is susceptible to disease before the 5th leaf stage, and the resistance is enhanced after the 10th leaf stage. In the diseased field, spring maize is generally heavier than summer maize, intercropping is more important than direct seeding, and the cultivation of corn in vegetable fields is serious. The incidence of corn in the vicinity of the field, vegetable fields, orchards, roadsides and canals, and low-lying areas High, well-managed, overgrown fields and low-fertilizer soils with weak soil fertility are also susceptible to disease.

 

Control method

 

During the period of illness, we adhered to the comprehensive prevention and control technology based on agricultural prevention and control and supplemented by chemical prevention and control. The core is to control the source of poison, reduce the source of insects, and avoid the harm.

 

　　 1. Choose resistant varieties.

 

　　 2 , corn is suitable for late sowing, try to make the corn seedling period avoid the first generation of gray planthopper or aphid activity.

 

　　 3 , remove weeds, eliminate poisonous sources and poisonous insects, reduce the harm.

 

　　 4. Strengthen field management. Combine the seedlings and the seedlings, remove the diseased plants in the field, concentrate on deep burial or burning, and reduce the source of infection. Scientific fertilization, watering, strengthen field management, promote corn growth and robustness, shorten the period of susceptibility, reduce the chance of drug transmission, and enhance the disease resistance of corn.

 

　　 5 , chemical control. (1) to the seedling planthopper, aphids and thrips chemical control to be performed as soon as possible, it can be 10% WP imidacloprid 3000 to 5000 times or 25% buprofezin WP 1000 ~ 1500 times uniform spray, For the ditch, roadside and weeds, it is necessary to focus on prevention and control, pay attention to prevention and control, intercropping corn fields, and reduce the harm of poisonous insects. ( 2 ) At the beginning of the viral disease, 20 % virus A wettable powder 400 times liquid or 1.5 % phytopathogenic emulsion 1000 times liquid may be sprayed . (3) The insecticide seed dressing, for example, 2 kg of maize seeds with 25% pymetrozine 5-8 grams against the dressing into a mother liquor (amount of water to 1 kg against the corn seed against preferably 50 g), dry After sowing, it can prevent and control the gray planthopper in the corn seedling stage, so as to control the spread of the corn rough virus.

    Author: Chen Xiaowen Xu Ye Chenjiang Feng

Source: Agricultural Science and Technology News