There are different opinions about the origin of tea drinking in Zhong country: some people think that it originated in ancient times, others think that it originated in Zhou, Qin and Han Dynasty, Three Kingdoms, Northern and Southern Dynasties and Tang Dynasty. The main reason for the divergence of opinions is that there was no word "tea" before Tang Dynasty, but only the word "tea" was recorded. Until Lu Yu, the author of the Tea Sutra, the word "tea" was written in one picture. Tea ", so there is a saying that tea originated in the Tang Dynasty. Others are still said to have originated from Shennong and Qin and Han dynasties. Hawthorn Tea,Cynomorium Songaricum Tea,Radix Heterophylla Sweet Taste,Health Preservation Tea Lixian Spring Pharmaceutical Co., Ltd. , http://www.lxctyy.com
First, the main symptoms of eggplant seedlings, the incidence of small, adult plants began to appear more symptoms after fruiting, the results of the initial incidence of the most prosperous. Most of the symptoms began to appear in the lower and middle parts of the plant. The leaves began to turn green and yellow between the leaf margins and veins, and then gradually turned brown. The edges of the leaves curled upwards and finally fell off. At the early stage of disease, the diseased plant appeared wilting at high temperatures in sunny days, and it could recover sooner or later, and would not recover after being seriously ill until the diseased plant died. Some plants showed symptoms from one side of the leaves and expanded upwards, causing half of the leaves of the plants to turn yellow, or half of the leaves turned yellow and twisted to one side. It is easy to be confused with eggplant wilt disease in the latter part of the disease. Symptoms of verticillium wilt on eggplant include three types: dead type, macular type, and yellow mottled type. Regardless of the type of symptoms, they are all plant-based diseases. Roots, stems, branches, and petioles of the necropsy show brown vascular bundles. , squeeze squeeze the broken section without milky white turbid fluid exudation, can be distinguished with bacterial wilt.
Second, the incidence of the law
1. The pathogen Verticillium nigrescens Pethybr. called Verticillium sp. In addition to endangering the eggplant, it also harms tomatoes, sweet peppers, melons and so on.
2. Mode of transmission Pathogens mainly include mycelium, chlamydospore, and microsclerotia, which are overwintering in the soil with the diseased body, and may also be borne by the seeds. The bacteria in the soil can survive for 6 to 8 years. The overwintering germs are spread by fertilizers mixed with diseased bodies, and soils with bacteria or solanaceous weeds, through wind, rain, water, seeds, and agricultural operations. At the beginning of the year, infestation occurred mainly from wounds on the roots of plants or directly from the epidermis and root hairs of young roots. Germs germinated under suitable conditions, grew and propagated in vascular bundles, and dispersed along the flow to stems, leaves, and fruits.
3. Onset conditions According to observations, in the case of temperature of 19-25 °C, soil moisture or watering too many times, the incidence rate is higher; in addition, continuous cropping, soil viscosity, low-lying, low ground temperature (15 °C or less ) Frequent occurrence of cold air, partial application of chemical fertilizers, resulting in soil acidification, nutrient imbalance, etc., lead to poor growth and development of eggplant, reduced resistance to diseases, and is conducive to the infection of pathogens, accelerating the occurrence and spread of diseases. Diseases are inhibited when the temperature exceeds 30°C.
Third, the prevention and treatment method Verticillium wilt is a relatively difficult disease prevention and control, should take the main agricultural control, supplemented by chemical control measures integrated prevention and treatment.
1. Agricultural control (1) Selection of disease-resistant varieties Common early-maturing and low-temperature resistant varieties have strong resistance to Verticillium wilt.
(2) Crop rotation with non-solanum crops such as onions and garlic, and where conditions permit, can practice paddy-upland rotation, implement greenhouse eggplant (winter, spring)-single-season rice cultivation, and the occurrence of verticillium wilt every year is very high. light.
(3) Grafting and disease prevention With Toruubam, Maofen 802 and other materials as rootstocks, the disease prevention effect is better.
(4) Formaldehyde sterilizes at high temperature in the greenhouse. Soil is sterilized on plots planted with eggplant (tomatoes) for consecutive years. During the summer relaxation period of plastic greenhouses, continuous high-temperature weather is selected. After deep-turning the soil, it is drenched with water in the evening and the next morning. Spray 40% formaldehyde solution. Specific usage: Each standard greenhouse (6m30m) formaldehyde dosage of 1.5 ~ 2.0kg, add water 25kg uniform spray, immediately after spraying covered with plastic film or greenhouse film, sealed 10 to 15 days, pay attention not to leak.
(5) Strengthen field management and rational fertilization. Eggplant is a thermophilic, heat-resistant, hi-fertility and fertilizer-tolerant crop. Therefore, we must do a good job in the insulation of greenhouses; 2 do scientific fertilization, adequate application of phosphate fertilizer and maturity of organic fertilizer at the seedling stage, increase the application of potash fertilizer and nitrogen fertilizer during flowering, while artificially adding carbon dioxide gas fertilizer in greenhouses, Can solve the lack of carbon dioxide in the greenhouse impact on production, after the harvest of the door tomato timely dressing and spraying 1.8% love more than water 4000 to 5000 times liquid, green Fenwei No. 2 800 to 1000 times and other foliar fertilizer, enhance plant The disease resistance.
2. Chemical control (1) Liquid soaking Seed soaking with 50% carbendazim wettable powder 500 times liquid for 1 ~ 2h before sowing, then germination sowing.
(2) Nursery seedbeds (nutrition ridges) After the application of soil to prevent seedlings from leveling, use 50% carbendazim WP 5g per m2, mix with fine soil and apply to the sorghum surface, and sow.
(3) In the early stage of disease prevention and control, 86.2% of master copper wettable powders can be used for 1500-2000 times, 50% carbendazim 500 times, and 75% Zhimoling WP 500 times. Irrigation liquid 0.5kg, irrigation 10 days or so, and irrigation 2 to 3 times. Severe strains should be removed in a timely manner.
Eggplant Verticillium wilt, commonly known as half mad, half yellow, is one of the main diseases of eggplant. Eggplant verticillium wilt disease mostly occurs after the fruit is set in the eggplant, and the diseased plant grows sharply in the fruit period. At the early stage of disease, the middle and lower leaves of the plant chlorosis or chlorosis between the leaves and veins gradually develop upwards, leaving the branches and leaves to become yellow and dead, and the fruit is not rigid. Therefore, it is also called half mad. In severe cases, the whole plant withered, the leaves fell off and became light poles. Peeling the roots and stems, the vascular bundle becomes brown, so it is also called black heart disease.