Control of common diseases of tulip

Tulip, also known as lotus, is a bulb flower of Liliaceae. It is loved by people because of its colorful, rich, graceful flowers, long flowering period, wide variety and so on. However, in the production of tulips, various diseases often occur, which not only cause the loss of yield, but also seriously affect the ornamental value. In this paper, several common diseases in tulip production are listed, and the control measures of cultivation management and chemical control are put forward.

1 gray mold

1.1 symptom recognition

It mainly harms leaves, flowers and bulbs. After the leaves and flowers were damaged, brown spots appeared, most of the leaves and flower stalks rotted, and the stems also rotted. After the corm was infected, the outer scales rotted and produced many dark brown sclerotia. In wet weather, the disease department produces a gray mildew layer. The plants from the susceptible bulbs are dwarf, yellowish green, and the flowers wither. The disease is a fungal disease and the pathogen is. The pathogen overwintered with sclerotia in the remains of diseased plants or soil and became the source of infection in the following year. Germs spread through Rain Water and airflow. Rainy, foggy and dewy weather with high humidity is conducive to the occurrence and spread of diseases. The incidence of overdense planting, poor ventilation or surrounding weeds are more serious.

7.2 Prevention and control methods

① implements rotation, renews seedbed soil or soil disinfection before planting. Disinfection can be achieved by 70-80 ℃ steam treatment for more than 30 minutes, or chemicals can be used for disinfection, that is, 1000-fold solution of methyl topiramate is used to irrigate the soil, and then sealed with film for 7 days. Commonly used disinfectants include benzimidazole, benzoate, formaldehyde and so on. Before planting, ② examined the bulbs carefully, removed the diseased balls, and disinfected the bulbs. The method of disinfection is to soak the bulb in 0.3%-0.4% copper sulfate or 2% formalin solution for 30 minutes, then wash it with water, dry and plant. During the growing period of ③, diseased flowers, diseased leaves and diseased plants were removed in time and destroyed. At the initial stage of ④, spray 50% benzoate 1000 times, 5% Nongliling wettable powder 800 times, or 50% propofol 1000 times. Spray once every 10 days, 2 times in a row.

(2) broken color disease

2.1 symptom recognition

The damaged leaves appear light green or gray stripes, sometimes forming flowers and leaves. Broken flowers are produced on red or purple varieties, with pale spots or stripes of varying sizes on the petals. On the varieties of light and white flowers, the petal symptoms are not obvious, which is due to the lack of anthocyanin in the petals themselves. In severe cases, the plant does not grow well. The pathogen is tulip broken color virus (TulipBreakingVirus.), which overwinters and summers with sclerotia in bulbs and soil. it is transmitted by aphids during growth, and can also be transmitted by knives and scissors used when cutting flowers.

2.2 Prevention and control methods

① selected non-toxic plants as propagation material. ② removed the diseased plant in time. ③ sprayed 1000 times of 40% dimethoate EC, or 1000 times of 10% dimethoate wettable powder, or 2.5% of rotenin 800 times to control aphids and cut off the route of transmission. When cutting flowers with ④, the knife scissors should be heated and sterilized or washed with lotion before use.

3White silk disease

3.1 symptom recognition

The whole plant withered, the stem base was wrapped around white fungal cord or rapeseed tea brown sclerotia, and the affected part became brown and rotten. A large number of white fungal cords and tea-brown fungi can be seen on the soil surface. The pathogen is a semi-known subphylum fungus. The pathogen overwintered with sclerotia or fungal cords in the soil with the remains of the disease. when the conditions were suitable in the following year, the sclerotia or fungal cords produced hyphae for primary infection. The silky filamentous hyphae produced by diseased plants extend to contact with adjacent plants or sclerotia and re-infect by water flow to spread the disease. Continuous cropping or soil clay weight and low-lying or high-temperature and humid years or seasons are serious.

3.2 Prevention and control methods

① found that the diseased plants were removed and burned in time, and the diseased point and its adjacent plants were irrigated with 5% Jinggangmycin water 1000-1600 times, or with 50% Tianan water 500-fold solution, 90% Dexong wettable powder 500-fold solution, 0.4 × 0.5L per hole. ② combined with ploughing, mixed with 100~150kg lime powder per mu, slightly alkalized the soil and inhibited the breeding of Alternaria alternata.

4 mosaic disease

4.1 symptom recognition

There are mosaic-like markings and chlorotic stripes on the leaves, sometimes necrotic spots, and dark spots on the petals. Growth and development are inhibited. When the symptom is serious, the bulb does not grow big, the damage is big. The pathogen is cucumber mosaic virus (CMV). The virus is transmitted through the sap of diseased plants, and aphids are the vectors of transmission.

4.2 Prevention and control methods

① cleared the diseased plants and burned them in time. ② uses virus-free healthy bulbs as breeding material. ③ controls aphids with 1000 times of 40% dimethoate EC, or 1000 times of 10% dimethoate wettable powder and 2.5% rotenin 800 times.

5 Brown spot

5.1 symptom recognition

Damage to tulip leaves and flowers, causing leaves and pedicels to rot. The disease spot is light gray, the edge is brown. Damage at the seedling stage often causes the plant to bend and eventually die. Under wet conditions, the diseased part produces a gray mildew layer, that is, conidia. The corm was damaged, the whole plant was dwarfed, the stem base and outer scales of the corm rotted, and produced many light black or dark brown sclerotia. The pathogen is Botrytis cinerea, which is common in tulip cultivation areas. The rainy season is more serious and the air humidity is high, which is the main condition for the occurrence and spread of the disease. Overwintering with mycelium and sclerotia in rotten bulbs and soil.

5.2 Prevention and control methods

Remove the diseased bulbs before planting ① and soak the bulbs in 0.3%-0.4% copper sulfate or 2% formalin solution for 30 minutes. During the growing period of ②, diseased leaves and flowers were removed in time and destroyed. Once the bud or bud with symptoms of the disease is found in ③, it should be removed immediately to control the development of the disease. In the early stage of the onset of ④, 50% prohydantoin can be sprayed with 1000 times liquid, 50% Sukeling 2000 times liquid, 50% carbendazim 1000 times liquid. Spray once every 10 to 15 days for 3 times in a row.

6 basic rot

6.1 symptom recognition

It belongs to the genus Alternaria, which mainly harms the seed bulb. During the growing period, the damage of the seed bulb led to the yellowing and wilting of the leaves, less roots and water-stained bluish gray wet rot at the base of the bulb. The rotting tissue smells of pungent rosacea, and the disease spot is gray-white and calcareous after drying. During the storage period, the bulb was mainly characterized by glue flow, followed by yellowish brown dry rot. The pathogen is Fusarium oxysporum, which overwinters in susceptible bulbs and soil, high temperature in the production site and poor ventilation during storage are the main conditions for the epidemic of the disease.

6.2 Prevention and control methods

① should postpone planting and dig bulbs in advance to avoid the high temperature period as far as possible to avoid the harm of bacteria. ② healthy bulbs and diseased bulbs should be stored separately in a cool, ventilated place (less than 15 ℃). ③ planting should not be too dense, diseased plants should be removed in time during the growth period. Within 48 hours of digging up the bulb, ④ was immersed in 2000 times aqueous solution of 50% benzoate wettable powder for 15 minutes, dried and stored. ⑤ chooses disease-free bulbs and implements 3-year rotation system.