Introduction of symptoms and control methods of powdery mildew of Lycium barbarum

Lycium barbarum powdery mildew is also called Lycium barbarum leaf spot, which is mainly harmful to leaves and fruits. The leaf infected with the disease is round to nearly round, the size is 2mm, the edge of the spot is brown, the center is gray, the back of the leaf is often black-gray mildew, and the fruit is infected with similar symptoms. Let's take a look at the prevention and control methods of Chinese wolfberry powdery mildew.

Develop symptoms

Lycium barbarum powdery mildew mainly harms the leaves, and the leaves are covered with white mildew spots (initial stage) and powder spots (later). White mildew spots and powder spots are not only the symptoms of the disease, but also the symptoms of the disease (pathogen conidiophores and conidia). In severe cases, the plant of Chinese wolfberry is white, which is quite eye-catching. The photosynthesis of diseased plants was blocked, which eventually caused the leaves to turn yellow and easy to fall off.

Induced pathogen

The pathogen of powdery mildew of Lycium barbarum is the genus Alternaria. In cold areas, the pathogen overwintered in the soil with the disease residue as a sexual fruiting body. In warm areas, the pathogen mainly carried out the initial invasion and re-invasion by apomorphic conidia, and completed the annual cycle of the disease, and there was no obvious overwintering period. Warm and humid weather or planting environment is conducive to the disease, but the spores of the pathogen have the characteristics of drought tolerance, which can still germinate and infect the disease normally under the condition of high temperature and drought.

Disease condition

The pathogen of powdery mildew of Chinese wolfberry overwintered with mycelium or conidia in the withered branches and leaves of Chinese wolfberry or in the soil with diseased fruit, and the conidia spread through wind and rain in the following year to carry out primary infection and re-infection to expand the damage. It is easy to suffer from high temperature and rainy years, high soil moisture, moist air, lack of soil fertilizer and plant weakness.

Prevention and cure method

1. Select improved varieties of Lycium barbarum, such as Ningqi No. 1, clean the Qi garden in time after falling leaves in autumn, remove diseased leaves and fruits, concentrate and bury deeply or burn them, so as to reduce the source of bacteria.

2. Strengthen cultivation management, advocate compost made by Japanese enzyme bacteria retting, increase phosphorus and potassium fertilizer, and enhance disease resistance.

3. In June, 70% mancozeb wettable powder 500 times liquid or 75% chlorothalonil wettable powder 600 times liquid, 64% poison alum wettable powder 500 times liquid, 30% green Debao suspension 400 times liquid, once every 10 days or so, continuous prevention and treatment for 2 times 3 times, and stop using drugs 7 days before harvest.

Symptoms and control methods of powdery mildew of Lycium barbarum

What are the symptoms of Chinese wolfberry powdery mildew? What is the pathogen of Chinese wolfberry powdery mildew? What are the conditions for the onset of Chinese wolfberry powdery mildew? What are the prevention and control methods of Chinese wolfberry powdery mildew? Today, the editor will share with you the knowledge about Chinese wolfberry powdery mildew.

Symptoms of powdery mildew of Chinese wolfberry

Also known as Chinese wolfberry leaf spot. Mainly for damage to leaves and fruits. The infected leaves are round to nearly round, the size is 2-4mm, the edge of the spot is brown, the center is gray-white, and the back of the leaf is often black-gray mildew. Fruit disease also produces similar symptoms.

Pathogen of powdery mildew of Lycium barbarum

Cercospora lycii Ell. Et Halst. It is called Cercospora of Lycium barbarum, which belongs to the subphylum of semiknowns. Fruiting body on abaxial surface of leaves, receptacle small, brown; conidium brown, 3-7 fascicled, apex narrowly and lightly colored, unbranched, upright or with geniculate nodes 0 murine 4, apex subtruncate, spore scar obvious, polyseptum, size 48 min 156 × 4 MUE 5.5 (μ m); conidia colorless, transparent, flagellate, straight or slightly curved, base subtruncate, apical or apical, septum numerous, inconspicuous, size 66m 136 × 2f4 (μ m).

Transmission routes and pathogenic conditions of powdery mildew of Lycium barbarum

The pathogen overwintered with mycelium or conidia in the withered branches and leaves of Lycium barbarum or in the soil with diseased fruit, and the conidia carried out primary infection and re-infection by wind and rain in the following year. It is easy to suffer from high temperature and rainy years, high soil moisture, moist air, lack of soil fertilizer and plant weakness.

Control methods of powdery mildew of Lycium barbarum

(1) choose improved varieties of Lycium barbarum. Such as Ningqi No. 1. Clean the Qi garden in time after falling leaves in autumn, remove diseased leaves and fruits, and concentrate on burying or burning them, so as to reduce the source of bacteria.

(2) strengthen cultivation management, advocate compost made by Japanese enzyme bacteria retting, increase phosphorus and potassium fertilizer, and enhance disease resistance.

(3) in June, 70% mancozeb wettable powder 500 times liquid or 75% chlorothalonil wettable powder 600 times solution, 64% poison alum wettable powder 500 times solution, 30% green Debao suspension 400 times solution, once every 10 days or so, continuous prevention and treatment for 3 times. Stop using medicine 7 days before harvest.

How to control the damage caused by powdery mildew of Lycium barbarum

How to prevent and cure Chinese wolfberry powdery mildew? Have you mastered all the prevention and control methods of Chinese wolfberry powdery mildew? Next, the editor will introduce the prevention and control methods of Chinese wolfberry powdery mildew to you in detail to help you better grow Chinese wolfberry.

Control methods of powdery mildew of Lycium barbarum L.

1. Reasonable close planting, Chinese wolfberry should maintain good ventilation and light transmittance in the field during the growth period, so as to reduce the incidence of powdery mildew. For over-dense branches and overlapping branches, it can be loosened appropriately, and sprayed with new high-fat membrane to isolate bacteria infection, improve plant resistance to natural disasters and photosynthetic intensity, and protect the growth of Lycium barbarum.

2. Strengthen the field management, remove the diseased remains and fallen leaves in time, and take them out of the field for deep burial or burning treatment, so as to reduce the infection source of powdery mildew in the field.

3. Timely spraying and control, spraying targeted chemicals and tree protection generals at the initial stage of powdery mildew damage, spraying once at intervals of 7-10 days and spraying 2-3 times continuously, in order to consolidate the control effect, improve the resistance and immune positive energy of Lycium barbarum, and protect its healthy growth, high yield and high quality.