Anthrax decryption

Colletotrichum gloeosporioides has many kinds of pathogenic bacteria, which harm orchid leaves with similar symptoms, sometimes difficult to distinguish, also known as leaf spot disease. Anthracnose pathogen optimum growth temperature of 22 - 28 degrees, spring and autumn rainy season or plum rain season and orchid is budding or flowering, orchid growth is weak, most susceptible to disease.

Colletotrichum gloeosporioides pathogen mostly damages the leaves of orchid plants, and occasionally can be found on pseudobulb stems. When Chinese orchid plants are damaged by mechanical injuries such as sun injury, cold injury, external friction injury and root damage, resulting in weak growth potential of orchid plants, they are most vulnerable to Colletotrichum gloeosporioides pathogen damage. Black spots will appear near the tip or back of leaves, gradually expanding into irregular disease spots. Brown ring gangrene spots appear on the leaves, gradually expanding into large light brown spots, slightly sunken. When anthrax is severe, old leaves sometimes yellow and fall prematurely.

Control methods:

(a) anthrax has a wide host range and is often spread by splashing water. During cultivation and management, try not to keep the leaves wet for too long, and avoid watering the whole plant in the way of water supply, so as to avoid the harm of anthracnose, affect its photosynthesis ability, and limit the growth of orchid roots.

(2) Strengthen the cultivation and management of Chinese orchids, cultivate strong orchids, and avoid pathogenic bacteria infection caused by artificial or mechanical abrasion.

(3) Avoid the weakening of orchid growth caused by cold damage or sun damage, and reduce resistance to pathogenic bacteria.

(4) excessive nitrogen fertilizer, orchid tissue is soft, pathogenic bacteria easy to invade harm. Organic plant growth promoter low nitrogen high phosphorus potassium fertilizer should be applied more to benefit disease resistance.

(5) Keep the leaves upright, the leaves droop, the tips of the leaves are more likely to retain water droplets, the tips of the leaves are more likely to be infected, and the tips of the leaves are burnt.

(6) Leaves should be kept as dry as possible in susceptible seasons.

(7) Prevention is more important than cure, and it should be used in full:

(a) a thousand times 70% tetrachloro WP;

(b) 40% putrefied WP 2000 times;

(c) 50% Dykonium WP 1000 times;

Add Water Spreader to increase potion by 1500 times. Every 10-14 days in summer and 20 - 30 days in winter. When spraying, make sure that the leaves are evenly moist, and the finer the spray particles, the more effective they are.

(8) When infected, the diseased leaves should be cut off and burned to avoid re-infection of other healthy leaves. Immediately use 70% Tetrachloropuridine WP 600 times, once every seven days, three consecutive times to control the disease. Do not sprinkle water within two days after application, so as not to affect the bactericidal effect.

Anthracnose control is closely related to the choice of pesticide species, application time and application method of Chinese orchid cultivation managers. The occurrence of anthracnose, the initial disease is mostly infected by the back of the leaf, cultivation managers usually apply chemicals for disease control, the spray equipment used, its pressure, spray fineness is insufficient, spray does not thoroughly spray the leaf surface and the back of the leaf, the pathogen can not be completely eliminated, until the appropriate environment and sufficient nutrition sources, the pathogen will spread again. When the disease spots spread, the leaf function will be reduced, and the quality and yield will be greatly reduced.

Therefore, anthrax prevention and control work is a very important work. As long as the cultivation manager carries out the control work before the rainy season and regularly uses the effective medicine against anthracnose. Spray the orchid plant and surrounding orchid room with the most fine spray method, especially the back of the leaf is the most important. And regularly remove dirt from the floor of the orchid room, so that the cultivation manager will not suffer losses due to anthrax infection.