Major Diseases of Carrots and Their Control Techniques
Glass Container,Medical Supply,Mini Glass Bottle Zhejiang Sorfa Medical Plastic Co., Ltd. (Ningbo Jiangdong Aron Imp&Exp. Co.LTD) , http://www.sorfapipettes.com
In recent years, the carrot planting area has rapidly expanded. Due to factors such as poor production management, carrot diseases have gradually increased. According to the survey, the incidence of field crops is generally 10% to 30%. The common diseases are black spot, black rot, root knot nematode, soft rot, mosaic disease. 1, black spot identification points: mainly damage the leaves, petioles and stems. The leaves mostly developed from the leaf tip or leaf margin, resulting in brown small lesions with yellow halos. After expansion, they were irregularly shaped dark brown, with internal pale brown lesions, and later on the leaf margins were rolled up and yellowed from the lower part. When wet, dense black mold on the lesions, stem, pedicel disease, resulting in a dark depression of oblong dark brown spots, easy to break. Control methods: (1) Before seeding, seed dressing with 0.3% seed weight of 50% thiram or 70% mancozeb. 2 Seeds are collected from disease-free plants so that they can be collected in a single collection. 3 2 years of rotation, adding basal fertilizer and top dressing. 4 At the beginning of the disease, 75% of chlorothalonil 600 times solution and 70% of mancozeb manganese 600 times solution were sprayed at the beginning of the disease, and the control was continued 2-3 times every 7-10 days. 2. Identification of black rot: From the seedling stage to the harvesting stage or the storage period, it can occur. It mainly damages the fleshy roots, leaves, petioles and stems. The leaves become infected and dark brown spots are formed, causing serious death of the leaves. Petiole long strips. Most of the stems were spindle-to-striped, with no obvious lesions on the edges. When the humidity is high, the surface of the black mold layer is dense. Most of the root infections of the fleshy roots have irregular or round dark spots on the root head. In severe cases, the lesions spread and deepen to the inside, making the fleshy roots black and rot. Control methods: Black spot with carrots. 3, root knot nematode disease identification points: mainly occurs in the root. Symptoms of above-ground performance differ depending on the degree of disease. Mildly ill strains have no obvious symptoms. Severe diseased plants have poor growth and development. Leaves wilt or yellow gradually at noon. Plants are dwarf and affect fruitfulness. When the disease is severe, all fields die. After the infection in the ground, it produces root knots of different sizes and dissections. There are many tiny milky nematodes embedded in the diseased tissue. Control methods: 1 The implementation of flood and drought rotation for more than two years. 2 seriously ill field irrigation 10-15 cm deep, keep 1-3 months, so that the nematode suffocation died of hypoxia. 3 After the harvest, the garden should be thoroughly cleaned, and the diseased body should be brought out of the field to be burned and burned, which will reduce the number of insects and reduce the occurrence of diseases. 4 In the early stage of the disease, the roots were irrigated with 1.8% of chlorpyrifos 1 000-fold, and 0.5 kg per plant was irrigated once every 10-15 days. 4, soft rot disease identification points: mainly damage the bottom of the fleshy root, field or storage period can occur, in the field above the stems and leaves become yellow wilting, the roots were infected at the beginning of the disease was wet rot, after the expansion, the shape of the lesion is uncertain, the edge Obvious or insignificant, the fleshy root tissue is softened, gray-brown, and rot juice overflows with odor. Control methods: 1 heavy ward is implemented with onions and garlic vegetables and rice rotation. 2 Strengthen the inspection. Drain the water immediately after the rain and find that the diseased plants are cleared at any time and lime or lime water is used to shower the diseased points. 3 At the beginning of the disease, spray 14% solution of ammonia and 300 times solution of copper, or 50% solution of copper carboxylate (DT) 500 times. 4 To minimize the wound when harvesting, after harvesting for half a day, after entering the cellar, strictly control the cellar temperature below IO °C, relative humidity below 80%, can reduce the incidence. 5, mosaic virus disease identification points: carrot seedlings or mid-growth occurs, plant growth and vigorous blade damage, light form a significant mottled mosaic, severe cases were severely wrinkled mosaic, some leaves distortion distortion. Control methods: 1 clean the garden, timely clean up the sick, buried or burned. 2 Control locusts early to reduce transmission opportunities, using 2.5% kung-fu 3 000-4 000 times or 10% imidacloprid 15 g/mu. 3 spray with 1.5% plant disease Ling 1000 times, or 1: (20 ~ 40) fresh milk low-volume spray, spraying every 7 days, and even spray 3-4 times.