Maize rough dwarf disease is a maize virus disease caused by corn roughage virus (MRDV). It is endemic in corn production areas in northern China and is transmitted by the planthopper in a persistent manner. Laodelphax striatellus is a major poisonous insect, which has the habit of migrating with air flow and landing with rainwater. It can spread corn rough dwarf virus to healthy corn plants through sucking juice. In recent years, the occurrence of rough dwarf diseases has caused severe reductions in corn production. Maize seedling stage is a sensitive period of dwarfing disease. At present, northern corn is sown, so it is necessary to prevent rough dwarf disease early in seedling stage. Symptoms and characteristics: corn can be infected during the entire growth period, with the most severe disease at the seedling stage, the diseased plant is obviously dwarfed, and the height is less than half of the healthy plant. The leaf color is dark green, wide and short hard, and it is on the opposite side. Wax white protrusions appear on the lateral veins and the roughness is evident. The diseased plants have more tillers and the roots are underdeveloped and easy to pull out. Most of them fail to produce heading and fruit. Although some tassels can be extracted, they have very few branches and no pollen. Transmission routes and disease conditions: mainly rely on Laodelphax striae. Adults and nymphs of Laodelphax striatellus were overwintering in weeds in the fields and moved into corn fields in late spring. In addition winter wheat is also one of the viral wintering sites. The corn was susceptible to disease before 5 leaves, and the resistance increased at the 10-leaf stage. The occurrence of the disease is related to the number of poisonous planthoppers and the cultivation conditions. The emergence of corn to the fifth leaf stage is likely to occur when the insects encounter the peak of the insect transfer. Sets of crops, early sowing and weedy corn fields are more serious. The incubation period is 10 to 20 days. Maize seedling stage is a sensitive period of corn rough dwarf disease. Comprehensive prevention and control measures: In the prevention and control of corn rough dwarf diseases, we must adhere to an integrated prevention and control policy based on the prevention and control of agriculture and supplemented by chemical control. Its core is to control the source of poisons, reduce the source of insects, and avoid hazards. 1. Strengthen monitoring and forecasting. In disease-prone areas, we will focus on spotting and regularly investigating the disease rate and severity of wheat, field weeds, and corn rough dwarf diseases. We will also investigate the occurrence density and the rate of poisoning of SBPH. The timely and accurate prediction of the occurrence trend of corn rough dwarf disease will be conducted to guide the prevention and control of the field. 2, choose resistant varieties. Although the main cultivars currently used in corn production have certain disease resistance, they lack the strong cultivars with strong disease resistance, and there are still some differences in susceptibility between cultivars. Therefore, according to local conditions, select relatively resistant varieties, at the same time pay attention to a reasonable layout, to avoid the large-scale planting of a single resistance source varieties. 3, adjust the sowing date. According to the law of occurrence of corn rough dwarf disease, sowing time should be adjusted in disease-recurring areas. Maize avoids the high incidence of adult Spodoptera sinensis during the most sensitive breeding period and reduces the incidence rate. 4, remove weeds. Weeds on the ground and in the fields are not only the provenance of weeds in the farmland in the coming year, but also the winter and summer hosts of the poisonous mediator Laodelphax striatellus. Before and after maize sowing, chemical weeds are used to remove large areas of weeds in fields and fields to reduce the source of poisons. 5. Strengthen field management. Rational fertilization and watering, strengthening of field management, promotion of corn growth, shortening the seedling time, enhancing the resistance of corn to disease resistance, and reducing opportunities for drug transmission. In combination with Dingmiao, the diseased plants in the field were removed, concentrated or burned, and the source of invasive dwarfing disease was reduced. 6, pharmaceutical control. Promoting the use of pharmaceutical coated seeds can prevent and control underground insect pests and some pests and diseases in corn seedlings. On the basis of using chemically coated seeds, the key crops for maize rough dwarf disease are 10% imidacloprid wettable powder 20 g or 4.5% efficient in the period of poisoning of Laodelphax striatellus, especially before the 7-leaf stage of corn. The cypermethrin EC is 30-45 ml/mu, plus virus A, spraying 30 kg of water, once every 6 to 7 days, and even spraying 2 or 3 times, it can prevent and control thrips and locusts, and it can also effectively control aphids, which can effectively prevent worms. The occurrence and spread of corn rough dwarf disease. 1% salidroside in rhodiola rose extract is a kind of rhodiola rose extract, is the Key Product of our company, with the stem and leaves of rhodiola rhodiola as raw materials, after extraction, concentration, drying into brown powder. Rhodiola Rosea,Rhodiola Rosea Powder,Rhodiola Rosea Extract Benefits,Rhodiola Rosea Extract Holland Shaanxi Kepler Biotech Co.,Ltd , https://www.keplerherb.com
Rhodiola rhodiola extract is a natural extract extracted from Rhodiola grandiflora, which is refined, concentrated and dried.It is easily soluble in water, soluble in methanol, soluble in ethanol, insoluble in ether.It's stable against heat.
Rhodiola, the name of traditional Chinese medicine.They are the dry roots and rhizomes of Rhodiola roseum, .Mainly produced in the Chinese mainland Jilin, Hebei, Shanxi, Xinjiang and other places."Traditional Chinese Medicine Dictionary" records: Rhodiola "cold, sweet and astringent taste.Promote blood and stop bleeding, clear lung and stop cough.Treatment of cough, hemoptysis, pneumonia cough.
Rhodiola rhodiola is commonly found wild on sunny slopes, stone crevices, alpine meadows, alpine rock crevices, hillside grasslands, shrub margins, and dry sandy soils in mountains.Its adaptability is strong, like slightly cold and humid climate conditions, cold and drought tolerance, soil requirements are not very strict, should choose high altitude, cold climate, short frost-free period, summer day and night big temperature difference in the mountain cultivation.
Loam or sandy loam with rich humus, deep soil layer, sufficient sunshine and good drainage should be selected for cultivation, and forest cut or raw wasteland can be used for cultivation in mountainous areas.