Medicinal plant vanilla stalk rot (blight)

Herbal Vanilla planifolia Ander. Synonyms V. Fragrams (Salish.) Ames, also known as citron, vanilla, are orchid evergreen vines. Medicinal whole plant.

Symptoms are also known as vanilla orchid root rot and blight. The results from the seedlings to adult plants can occur. Injured strains often begin to infect from the nodule, first as water-stained, dark-green spots, then as irregularly shaped, dehydration-like, brown vascular bundles, aerial roots on diseased stem nodes rot, yellow leaves, In humid conditions, the diseased area produces a large number of pink spore masses. The lesion progresses up and down, and the rate of decay depends on temperature and humidity. The appearance of stems without symptoms, the vascular bundle does not change color, the leaves are not yellow, the cuttings planted in sterile bacteria-free soil, does not rot, and will not die of the whole plant. The aerial roots of vanilla orchids are numerous and prosperous. If yellowing of the whole plant leaves occurs, causing the whole plant to wither and die, it is usually at the later stage of the disease. Unless invading from the roots at the beginning, the water supply in the ground gradually became insufficient and the plant growth became weaker, so the leaves turned yellow and wilted, and finally the whole plant died.

Pathogen Fusarium oxysporum Sclll. f. Sp. Vanillae (Tuck.) Gord. Synonyms F. Batatatis Wr. Var. Vanillae Tuck. The special type of Fusarium oxysporum f. On PDA medium, cultured at 25°C for 10 days: airborne mycelium was cotton-like, and the opposite side of the flora was white to pink, then became purple and purple, and a large number of conidia had been produced in about two weeks. Large conidiospores are sickle-shaped, thin-walled, pointed at both ends, colorless, slightly hooked to the top cells, podocytes at the base, 3–5 septa, and 5 cell sizes 30–603.5–5.5 (μm); small Conidia are produced on spore-formed spore-forming cells of conidiophores, colorless, ovate to reniform, cylindrical, 1-2 cells, size 6-173.0-4.8 ( Μm); about 3-4 weeks after the production of thick-walled spores, thick-walled spores spherical or oval-shaped, smooth wall, colorless, terminal or interspersed, single cell or two string students. In addition, Fusarium solani (Mart.) App. Et Wollenw called Fusarium oligospora, which has a sexual state of Nectria haematococca Berk. Et Br. Vanilla rot stalk rot (root rot, blight) can also be caused. For morphological characteristics, see stalk rot of passionflower.

Transmission Pathways and Pathogenic Conditions Both Fusarium spp. are hyphae and chlamydospore overwintering in host diseased tissues or soil and can survive in soil for several years. When the conditions of temperature and humidity are appropriate, a large number of spores can begin to be transmitted by irrigation water or wind and rain, agricultural implements, insects, and nematodes. They can also be invaded directly from the wounds caused by underground pests or nematodes and other causes. The incubation period is 4 to 28 days. The disease occurs throughout the year, especially in the rainy season from June to October, and it is heavier. Planted dense, soil water, easy to disease.

Control methods (1) selection of disease-resistant varieties. (2) Apply compost of decomposed organic fertilizer or fermented bacterium, do not apply partial fertilizer, apply nitrogen fertilizer, moderate irrigation, drain water immediately after rain, and prevent moisture from being trapped. Properly shaded, airy and light, ground covered. Prevent human wounds. (3) Cut off the diseased branches in time, remove the severe diseased strains, and spray 40% Sterile EC 250 times or 50% Carbendazim WP 300 times. Can also be used 50% dexamethasone 500 times the soil around the diseased plants, 7-10 days 1 time, a total of 2-3 times. (4) In the early stage of onset, spray 25% Benzophenone EC 800 times or 40% Sterilize EC 500 times, every 7-10 days for a total of 2-3 times.


Safety Coverall,Non-woven Protective Coverall,Laminated Protective Coverall,Breathable Protective Coverall


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