Occurrence and Control of Solanaceae virus Diseases

The winter climate in south Guangxi is warm and there is no obvious frost. It is a good place for winter vegetables to be transported from south to north. Therefore, winter vegetables should be planted after late rice harvest and supplied to market after Spring Festival. The economic benefit is relatively high. Another new chapter of "one year's plan lies in autumn and winter" has become another way for local farmers to become rich and well-off. Among many vegetable varieties planted, Solanaceae (tomato, pepper, eggplant) vegetables are favored by local farmers for their unique planting advantages. According to statistics, the perennial planting area is about 80,000 mu, and it is predicted that the planting area will increase year by year. However, in the process of planting for many years in Hepu County, the virus disease known as "plant cancer" caused "three-drop disease"(leaf falling, flower falling and fruit falling), which brought great economic losses to vegetable farmers. According to the experience summarized in plant protection work for several years, the author talks about his own opinions on the occurrence and prevention of viruses for reference by vegetable farmers.

1. Disease identification

Its symptom basically has mosaic necrotic type and leaf deformity cluster two kinds.

(1) mosaic necrosis type

The diseased leaves showed obvious mosaic symptoms of light green and light green, some appeared brown necrotic spots, necrotic stripes occurred along the stem from the main veins of the leaves, falling leaves, falling flowers and fruits, resulting in the death of the whole plant.

(2) Abnormality

At the early stage, veins fade green, mottled leaves appear, leaves thicken, narrow, linear, stem internodes shorten, abnormal, branches cluster, late plants dwarf, fruits present dark green and light green mottled, diseased fruits abnormal, easy to drop.

2, the incidence of law

The transmission route of virus disease varies with different virus sources, but it is mainly divided into two categories: insect-borne and contact infection.

(1) mosaic necrosis type

The disease is caused by tobacco mosaic virus (TMV) and is transmitted primarily by contact with sap, invading through microwounds on plants. The disease condition is high temperature and drought, continuous cropping for many years, tender plant, poor soil and extensive management.

(2) Abnormality

The disease is transmitted by insects with cucumber mosaic virus (CMV), such as aphids and thrips. In high temperature drought, in aphids, thrips occur in large numbers when serious.

3. Prevention and control measures

At present, there is no specific medicine to prevent and control this disease, only through cultivation technology management early prevention and control measures such as aphids, thrips and other centralized control measures to prevent or effectively reduce the virus, to achieve the purpose of high yield.

(1) Selection of resistant varieties

Tomato varieties: Zhongza 7, Shuangkang 5, Zhongza 9, etc.

Pepper varieties are: Jinjiao No. 3, Tianza No. 1, Tianza No. 2, large persimmon pepper, etc.

Eggplant varieties are: Qingxuan No. 4, Fengyan No. 1, Liaoqi No. 3 and so on.

(2) Crop rotation to reduce disease

Solanaceae plants can not be continuously planted, but can be intercropped with sorghum, corn and other high-stalk crops, preferably with rice, etc., with good disease prevention effect. At the same time, it is required to cultivate strong seedlings, select seedlings without diseases, and combine formula fertilization technology, apply sufficient base fertilizer and water frequently. Make the plant grow healthily and enhance the ability of disease prevention.

(3) Control by application

Aphids and thrips are vectors for spreading Solanaceae plant viruses, so it is necessary to control aphids and thrips early to reduce diseases and achieve the effect of "both insect and disease treatment". 20% Kangfuduo emulsifiable solution 4000 times +20% virus A wettable powder 500 times + amino acid leaf fertilizer mixture solution, or 10% imidacloprid wettable powder 2500 times +2% Ningnanmycin aqueous solution 300 times, or 1.5% Zhibingling II 800 times mixed with leaf fertilizer chlorfenwei 1000 times solution, spraying the whole plant at the early stage of disease, continuous application 3~4 times, each time interval 7~10 days.