The occurrence and control of corn rough dwarf disease

Maize rough dwarf disease is an important disease in the corn producing areas in northern China. The area of ​​corn in Botou City is 500,000 mu, and the occurrence of corn rough dwarf disease is widespread. In recent years, the occurrence area and damage degree have been obviously increasing. Maize rough dwarf disease is a viral disease caused by the corn roughage virus (MRDV), which is commonly referred to by the masses as the "gun shaft," "little old seedlings," and "dwarfism." The virus is a double-stranded RNA spheroid virus transmitted by Laodelphax striatellus in a persistent manner, endangering a variety of grass crops and grass weeds, with corn most susceptible to disease.

First, the symptoms and hazards of corn can be the entire growth period, with the most severe victimization at seedling stage, 5 to 6 leaves can be obvious disease, began to produce transparent diarrhea dotted line on both sides of the base of the heart and the middle vein, and gradually expand The entire leaf produces waxy white uplift stripes on the main veins of the leaves, which are touched by hand and have a rough feel. The heart is curled. The width of the diseased plant leaves is short and thick, the leaves are dark green, the internodes are shortened, the diseased plants grow slowly and dwarf, and their height is less than half that of the healthy plant. Severely diseased tassels cannot be extracted or pollen-free, and when the ear is severe, the ear is deformed and can not be seeded or reduced, which can result in severe reduction of corn production.

Second, the incidence of disease law Laodelphaxidus corn is the main virus mediators of crude contractile virus, once the poisoning of Laodelphaxidas will be a lifelong virus, in the wheat, corn, weeds harm, and the formation of an annual cycle of infection. The virus can be wintered on winter wheat, wintered on perennial grasses and insects, and spread without viruses. In northern China, Sphaerophagalidae is wintering at the base of winter wheat field or two-year-old grass weeds with old nymphs, and from late March to early April of the following year, the winter nymphs of Laodelphax striatellus nymphs begin to be active and the wintering generations are completed on overwintering hosts. Overwintering adults lay eggs, hatching nymphs, and the nymphs develop into adult worms several times. The first generation of adult worms were obtained from the host plants of the overwintering host and acquired the virus, and they entered the middle of May and began to migrate. The peaks of the migration occurred in early June, and the corn rough dwarf disease appeared within 25 days after the migration peak of the planthopper. Significant peak, therefore, this period is the high incidence of corn rough disease. The maize seedling stage coincides with the peak of the transfer of poisonous Laodelphax striatellus, and the disease is severe. Maize 4 to 5 leaf stage is the most susceptible, and after 10 leaf stage disease resistance is enhanced and the incidence is reduced. Water and fertilizer management in corn fields can not keep up, weak seedlings, and slow growth are also conducive to disease.

Third, prevention and control measures The occurrence of corn rough dwarf disease is entirely caused by the infectious disease caused by SBPH, so eliminating or avoiding Smilax falciparum spread infection is an important way to prevent the occurrence of dwarfism. The core of prevention and control is to control the source of the disease. Reduce insects and avoid hazards.

1. Use resistant varieties. Use varieties with relatively strong disease resistance and promote contiguous planting.

2. Eradicate overwhelming insect sources. Before winter and spring sowing and corn planting, weeds in the field were cleared to eliminate the winter breeding sites of the planthoppers, reduce the sources of wintering poisons, and reduce the chance of transmission of poisons.

3. Adjust the sowing date. According to the law of the occurrence of corn rough dwarf disease, as far as possible sensitive period of corn sensitivity to avoid the first generation of migratory locusts adult migrating peak period (from late May to early June), appropriate late sowing.

4. Strengthen field management. Appropriate increase sowing volume, combined with seedlings Dingmiao, pull out the field diseased plants, centralized treatment, reduce the source of invasive disease. Rational fertilization and watering, increase organic fertilizers, phosphorus and potash fertilizers, promote seedlings and strong growth, enhance resistance to pests and diseases, shorten the period of disease, and reduce the chance of transmission.

5. Chemical control. The first is the dressing of the pesticide, which is mixed with 0.1%-0.15% of the seed amount with a pure special seed coating agent or 40% methylisothiphos and 20% virus A; the second is after the 2-3 leaf stage of corn to 5 Before the leaf stage, 10% imidacloprid wettable powder or 3% acetamiprid EC may be sprayed 1000 times to control Laodelphax striatellus, and 20% virus A and other virus passivation agents may also be used for prevention and treatment.

Our Consumable Laboratory Products is good in quality and competitive in price. We are manufacturer and supplier Consumable Laboratory Products following your specific requirement. The mainly products as following : Vacuum Blood Tube,  Slide,cover glass, Storage Box,pipette tips , Test Tube ,glassware items , Serological Pipette , Centrifuge Tube ,ESR tube , Freezing Tube , tube rack , urine container , petri dish , test strip ,pastuer pipette ,Lab. Reagents. We are looking forward to your E-mail and establishing cooperative relationship with you ! We would provide professional Consumable Laboratory Products with good services for you !

Consumable Laboratory Products

petri dish,test strip,pastuer pipette,Lab Reagents

Ningbo Cland Medical Instruments Co., Ltd. ,