Comprehensive analysis of boxwood wilting
Boxwood is a shrub species with small leaves, bright green leaves and lush foliage. Boxwood is mainly used as hedges and ornamental balls, planting is relatively simple, the greening effect is good, but after the ambush of the area of the large rainfall, so that the greening workers are very headache, do not know how the boxwood appeared a piece of leaves white, wilt seriously affected the overall landscape effect.
The greener prunes the diseased plants
Boxwood wilt is caused by stem base rot, stem base rot is mainly half of the pathogen infecting the rhizome, causing rhizome rot, mainly caused by one or more mixed effects of rot mold, Phytophthora, filaria and Fusarium, with strong saprophytes, serious can cause the whole plant to die.
It can not only harm the large-leaved boxwood but also harm the holly plants such as melon seed boxwood, phnom penchnant boxwood, and bird's tongue boxwood. The symptoms of this disease are: initially showing that the basal cortex of the stem is light brown or black brown, and later the base of the stem is shrunken, brown, decayed when the humidity is high, and a layer of white hyphae is born, circling around the base of the stem, some have lost water and shrunk, and the leaves have turned yellow and wilted, breaking open the xylem inside the stem and turning brown, and the disease continues to spread.
Pathogenesis:
Stem base rot is a soil-borne disease, soil carrier bacteria is the most important source of infection, pathogenic bacteria can be spread with the help of rainwater, irrigation water, re-impregnation under suitable conditions, in addition to the infection of pathogenic bacteria in the soil, there are high temperature, high humidity is also the main reason.
In the high temperature season, coupled with the planting is too dense, poor ventilation leads to excessive temperature at the bottom of the plant.
1. The nursery soil is sticky, poorly breathable and compacted
2. Weak growth of seedlings (plants with severe powdery mildew are particularly serious)
3. Continuous rainy weather
4, the land is rough, the seedbed is too low, the bed surface is uneven, the garden is waterlogged,
5, lack of organic fertilizer, poor soil
Prevention and control methods:
1. Preventive measures
1. Minimize the appearance of wounds and prevent plant injuries during transportation.
2, before colonization of the land is best to turn the sun disinfection, to avoid flood irrigation, remove disease residues, organic fertilizer rot, etc.: as little as possible or do not use chemical fertilizer, to avoid excessive nitrogen fertilizer, it is best to apply carbendazim and other fungicides for soil disinfection treatment;
3, high temperature and high humidity weather, it is best to spray carbendazim after rain, and the economy plays a preventive role.
Second, chemical control
1. When watering, see dry and wet watering.
2. At the beginning of the disease, 500 times spray + 600 times of heng root + tulebao spray + irrigation of plants are sprayed once every 5-7 days. Use 2-3 times continuously. Inhibits the propagation of pathogens, controls the development of diseases, and promotes root growth and improves resistance.
3, do not blindly spray medicine, but also in time to supplement the plant nutrition, with the spray of potassium dihydrogen phosphate foliar fertilizer, enhance the resistance of the plant, if there is a small area of disease, remove the diseased plant, soil disinfection, tonic seedlings, other seedling spray protection.