Occurrence Regulation and Ecological Control Techniques of Botrytis cinerea in Protected Vegetables
4-Amino-6-Chloro-1,Benzoic Acid,Cas 761446-44-0 Shijiazhuang Dingmin pharmaceutical Sciences Co.,Ltd , http://www.dingminpharma.com
First, the law of occurrence
1. Incidence site. Botrytis cinerea mainly damages young fruit, causing the young fruit to become soft, atrophic, rot, and a layer of gray mold on the surface. When young fruit is attached to the stem, it can cause stem rot. In addition, it also damages the flowers, leaves, vines and fruits of melons, as well as the leaves of leeks and the young fruits of eggplant, such as eggplant's door and eggplant.
2. The time of onset. In the solar greenhouse, gray mold can occur from the flowering of flowers. The flowering period and the period of fruit enlargement are the prosperous periods of flowers and fruits. Leaf vegetables are severe during the late growth period. Wintering a large amount of vegetables, often in the period from December to January is the peak period of onset, early spring in late April is the peak period of onset.
3. Relationship between humidity and disease. The investigation found that the humidity in the solar greenhouse was long and the leaves had a long time of condensation. The incidence of gray mold was early and the damage was heavy. The relative humidity of the air in the greenhouse is 70%-80% during the day and over 90% at night, which is the main cause of gray mold. Nectaries of leaves have a long time and are easily infested by Botrytis cinerea. It is the main cause of gray mold in leaves.
4. Temperature, light and disease relations. The occurrence of gray mold is related to the time and degree of low temperature in the solar greenhouse. The longer the time, the lower the temperature and the heavier the incidence. The temperature directly affects the greenhouse ventilation intensity. When the temperature is low, in order to ensure the temperature in the greenhouse, often do not ventilate or shorten the air release time, so that the indoor humidity is too high, and sometimes the relative humidity of 100%, promoted the occurrence and development of gray mold.
5. Cultivation management and disease relations. General indoor cultivation density is too large, poor ventilation and light transmission, too much nitrogen fertilizer, vegetables, long, disease resistance, irrigation time and irrigation methods are inappropriate, can lead to the spread of gray mold.
Second, the ecological control technology
1. Full film coverage, using drip irrigation technology. The ground coating can prevent evaporation of soil moisture, reduce humidity, and control disease occurrence. After planting seedlings in general, ridges and underdrain irrigation trenches are covered with ultra-thin membranes. Using drip irrigation technology such as hoses and infiltration pipes, the diseased leaf rate and disease rate in the greenhouse are effectively reduced, and the control efficiency is over 93.3%.
2. Remove streaks. In the flowering and young fruit expansion period, timely removal of the residual flowers that fall on the fruit surface and the ground is one of the key measures to prevent and control fruit gray mold. According to the survey, the incidence of deciduous flowers in the greenhouse is 46.7%, and no disease is observed in the leaves without attached flowers.
3. Ventilation increases carbon dioxide. Generally, in the mid-growth phase of the solar greenhouse, the air is discharged and the humidity is enhanced. After the sunrise in the morning, the room temperature rapidly rises to 25-300C, and the single temperature control is realized. Noon began to release the wind, so that the temperature dropped to 20-25 °C, the humidity dropped to about 70%. During the second half of the night due to lack of ventilation, the humidity increased, but the temperature dropped to 12-13°C, which is conducive to controlling the occurrence of Botrytis cinerea. When the outdoor temperature is higher than 12°C at night, it can be ventilated overnight to achieve dual temperature and humidity control, which not only reduces the temperature and humidity, but also increases carbon dioxide and improves its resistance to disease. At the same time, increasing carbon dioxide can increase CO2 through carbon dioxide fertiliser or wheat straw fermentation. According to investigations, the CO2 content is less than 800ppm, the incidence rate is 46.7%, the CO2 content is greater than 1000-1560ppm, and the incidence rate is 15%-19%. Therefore, the amount of CO2 in the greenhouse is also one of the main factors determining the incidence of gray mold. Reasonable fertilization can effectively control the occurrence of gray mold.
4. Adjust the plants. As the plant grows, it is necessary to hang the vine in time, hit the side branches, and destroy the middle and lower old leaves and diseased leaves of the plant. The functional leaves of cucumber should be kept in 13-15 slices. Tomatoes in winter and spring more than the use of 3 spikes for the first method of pruning, autumn and winter more than the use of 5 ear replacement method. Strictly control the sowing density of different vegetables, reduce the humidity in the field, and improve disease resistance.
5. Spray preventative film and biological agent prevention. Generally, after planting the vegetables, the whole plant will be sprayed with the plant disease prevention film agent - non-toxic high-fat film or the Beijing ZB plant anti-film agent 50 times, or sprayed with 2% Wuyimycin 200 times solution, and all can Effective control of the spread of gray mold.
6. Early onset of drug control. In general, on the center of the onset, 65% tebumycin wettable powder 600 times, or 50% polymyxin wettable powder 700 times, or 45% teicotin suspoemulsion 800 times, or 50% can be used. Trifluralin WP can be 500 times, or 50% nellikon WP 1000 times. When the plant is dense, it is better to control the control of gray mold powder dusting. After spraying, pay attention to dampness and proper control of watering. Or with 10% fast-king, 45% chlorothalonil smoke agent 250-300 grams / mu, the distribution of 8-10 points in the shed, ignited with dark fire closed the greenhouse, smoked 3-4 hours. Note that with other methods, use alternately.
7. Clean the protected land in time to reduce the source of infection. In the middle and late stages of vegetable growth, the litter is concentrated, and the greenhouse or the vegetable in the protection period is cut off. The roots and leaves are completely cleaned up, the soil is deep-frozen, the ground is roasted at high temperature, and the accumulation of gray mold is reduced in the soil. The incidence of Botrytis cinerea is extremely low.