Phone number 138*****867 Weihai readers to inquire: The year before last year I planted more than 2 acres of kiwifruit trees, had grown very well, but now married interface infection, bark around the dried up, disease The spots circled around the branches and the tree died. The female plant in the park died severely, and the male plant was lighter. I looked at the roots and saw that the roots grew well and were strong. What is this disease and how to prevent it?
The trunk of the diseased kiwifruit tree showed rot symptoms and shed red sticky liquids. The roots did not rot and the sprouts thrived. According to the symptoms described by the reader, the kiwifruit ulcer disease was initially diagnosed. The disease is a bacterial disease caused by the infection of kiwifruit of Pseudomonas syringae in the genus Monocytogenes. In the middle and early May, the germs were in danger. The disease spreads mainly through planting materials and fruits such as seedlings and scions. Seedlings are more susceptible to the disease than forests. The older the trees, the lighter the disease. High temperature conditions are conducive to disease. When the temperature is in the range of 20°C to 36°C and the surface of the host tissue stays wet for more than 20 minutes, the bacteria invade and cause the disease. Therefore, the rainfall and precipitation periods are the determinants of the epidemic. .
(A) the characteristics of the disease
1. Related to the variety. According to surveys and inoculation experiments, the incidence of wild plants, male plants, and rootstocks (plantlets) is very light. The susceptibility of the species is closely related to the density of stomatal distribution and the size of the stomata gap.
2. Related to the slope of the woodland. According to the survey, the disease occurred in the shade, semi-shady slope or mountain valley park, which low-lying valley, stagnant water more severe incidence.
3. It is related to meteorological factors. The disease is characterized by high humidity and low temperature resistance. The occurrence of the disease is mainly dependent on the humidity in the atmosphere. It is more severe in wet and rainy years and lighter in dry years.
4. It is related to the degree of closure of seedlings. The degree of occurrence of the disease increases with the degree of closure of seedlings, and the higher the density, the higher the chance of occurrence.
5. Related to age. The incidence of kiwifruit in 4 to 5 years is above 20%, and the morbidity from 1 to 3 years is much higher than 40%. This is related to the old stomata of old skin.
(II) Control measures
1. It is forbidden to draw seedlings from the epidemic area, and seedlings should be treated with seedlings. Disinfection treatment method is: Add 1% alcohol with 700 units of streptomycin solution per milliliter as adjuvant and sterilize for 1.5 hours.
2. Strengthen tending management and breed resistant varieties. In the winter, the litters with pathogenic bacteria are concentrated and burned. In early spring, pruning is used to remove pests, diseased leaves, leggy shoots, and drooping branches to reduce the source of infectious diseases. Wherever conditions permit, summer shoots should be removed. It is necessary to attach importance to breeding, breeding and planting disease-resistant varieties, phase out susceptible varieties, and fundamentally improve the resistance of high-quality varieties to ulcer disease.
3. Chemical control. After fruit collection or before winter, combine with orchard pruning, spray 1~2 times 0.3~0.5 Baume degree lime sulfur or 1:1:100 Bordeaux mixture; after spring, before germination, spray 1:1:100. Bordeaux fluid or 50% succinic acid (DT) WP 500 times; after germination to flowering stage can be sprayed with streptomycin 250 mg/kg, or 70% copper sulphate WP 1000 times or 50% plus Rhinnon (Spring Copper Chloride) wettable powder 500 to 800 times the liquid, sprayed at intervals of 10 days; trunk overflowing bacteria pus, the streptomycin can be applied to the sick with 300 mg/kg.
Oral Solution Veterinary Medicine
Antiparasitic For Dogs,Anti Coccidia Medicine,Oral Solution Veterinary Medicine,Antiparasitic Drugs For Animals
Shangqiu Meilan Biological Engineering Co.,Ltd , https://www.melanvaccine.com