Lily is often threatened by a variety of diseases during the cultivation process. Before and after emergence, there are often pests and diseases, and before the emergence, the scales, bulbs and bulbs rot and cannot emerge. Injured after emergence, the diseased plants die prematurely, reducing yield and quality.
The main diseases and insect pests of lily are lily virus disease, lily blight, leaf blight, white silk disease, bulb base rot, and insect pests, etc. These diseases often occur in combination, which increases the degree of harm.
1. Disease symptoms
Symptoms of diseased lilies with symptomatic viruses are:
(1) Lily mosaic disease
Lily suffering from lily leaf disease, the leaf surface is mottled and light and dark, the leaves are severely forked and twisted, the flowers are deformed or the buds do not open. Some varieties of seedlings can produce mosaic symptoms;
(2) Lily necrotic spot disease
Lily suffering from necrotic spot, some show latent infection, some produce chlorotic mottled, some have necrotic spots, and some varieties have twisted or distorted flowers in tongue-like shape;
(3) Lily ring spot
Lily suffering from bad spot disease, the lily leaves have necrotic spots, and the plant has no main stalk, no flowers or stunted growth;
(4) Lily cluster disease
For lilies suffering from cluster disease, the infected plants begin to have high leaf density and roll down, sometimes showing flat stem symptoms. As the plant grows, the top leaves are clustered and curled downward, and some leaves gradually turn yellow, light green or light yellow, resulting in streaks or mottled. Young leaves are infected and rolled downward and twisted, and the whole plant is dwarfed. By the flowering stage, symptoms are most pronounced, with small or non-blooming flowers.
2. Prevention methods
The prevention and treatment methods of lily virus disease are as follows:
(1) Choose disease-resistant varieties
Select disease-free mother plants for seed storage, and select healthy plant bulbs for propagation. If conditions permit, disease-free seed storage sites should be established, and diseased plants should be removed in time. Bulbs with diseased plants should not be used for reproduction. Its bulbs can be used as commercial products, but can no longer be reserved for seed use.
(2) Prevent contact infection
Do not touch plants with hands or tools to reduce the chance of virus infection.
3. Eliminate poisonous insects
(1) Virus diseases can be basically controlled by controlling aphids well. Generally, 10% aphid and lice net 2500 times solution or 2.5% dimethoate 2500~3000 times solution can be used for control. Especially in the case of high temperature and dry air, pay attention to control aphids.
(2) Spray 10% imidacloprid WP 1500 times or 50% pirimicarb ultrafine WP 2000 times lily in the growing season to control the transmission of aphids and insects and reduce the spread of the disease.
(3) In the early stage of the disease, start spraying 20% poison nemesis WP 500-600 times or 0.5% antidote No. 1 water 300-350 times, 5% Junduqing WP 500 times, 20% Vironing water-soluble powder 500 times liquid, once every 7-10 days, 3 times in a row.
(4) In the early stage of the disease, it can also be applied to prevent and control virus diseases. You can choose:
① 5% Junduqing 300~400 times solution; ② 3.95% virus kill gram 500 times solution; ③ ns-83 inhibitor 100 times solution; ④ 20% virus a 500 times solution; ⑤ Virus k500~600 times solution; Potassium acid 1000 times solution; ⑦ Antidote No. 1 200~300 times solution; ⑧ 2~3 kinds of Kangdufeng 300 times solution, alternately used, the above drugs are applied once every 7~10 days, 3~4 times in a row.
4. Timely treatment of diseased plants
Plants with severe virus disease must be pulled out in time and burned in a centralized manner.
5. Strengthen management and fertilization to promote growth
For mildly infected plants that are still able to bloom, management should be strengthened, and phosphorus and potassium fertilizers should be increased to enhance disease resistance and promote their healthy growth.
6. Cover grass moisturizing and preventing drought
In the case of high temperature, strong solar radiation, dry air and dry soil, it will be conducive to the occurrence of virus diseases. Covering grass between rows of planting fields can keep warm, reduce soil moisture evaporation, reduce soil temperature and temperature between plant clusters, and reduce the occurrence of virus diseases. Generally, 400 kg of dry straw is used per mu, and it is spread between the rows when the soil is neither dry nor wet in the seedling stage.
7. Planting crops to shade
High-stalk crops such as loofah and beans can also be planted on the border for shade. Pay attention to drought and drought prevention when it is dry.
