What kinds of orchids do you have? How to prevent and cure white silk disease?

Orchid is one of the ten famous flowers in China, one of the four gentlemen in flowers, and the city flowers of Baoding City, Longyan City, Yilan City, Guiyang City and Baoshan City. So, what kinds of orchids are there? How to prevent and treat white silk disease? Let me introduce you here.

1. What kinds of orchids are there?

There are many varieties of orchids, such as striped orchid, sclerophyllous orchid, hanging orchid, Shaye orchid, winter phoenix orchid, deciduous orchid, exclusive spring, sedge orchid, jian orchid, long leaf orchid, cymbidium, multiflower orchid, spring orchid, tiger orchid, beautiful orchid, yellow cicada orchid, cold orchid, rabbit ear orchid, jasper orchid, big root orchid, snow orchid, pearl dwarf, ink orchid, fruity orchid, spotted tongue orchid, etc., their colors are different, different posture, here select a few of them for introduction.

1. Cymbidium striatum: Epiphyte, Guangdong, Guangxi, Guizhou, and SE to S Yunnan, China, growing in sparse forests or thickets on trees or on rock walls beside valleys, 100-1100 m above sea level, flowering April-May, occasionally October; Leaves thickly leathery, 4-5, racemes with 20-35 flowers, sepals narrowly rounded to narrowly elliptic, petals narrowly elliptic, labellum nearly ovate, sepals and petals pale yellow to creamy yellow, labellum white or creamy yellow and densely chestnut brown longitudinally striated, slightly fragrant.

2. Shaye Lan: terrestrial or semiepiphytic plant of Guangdong, Hainan, S Guangxi, SW Guizhou, SE Yunnan, China (Mengzi, Yanshan, Malipo, Pingbian), born in well-drained, stony land or rock crevices under forests, 900-1600 m above sea level, flowering October to February of the following year; leaves banded, 4-12, racemes with 3-7 flowers, sepals linear to broadly linear, petals narrowly ovate, labellum ovate, sepals and petals yellow-green or apple-green, labellum pale or sometimes white or pale yellow, with lemon fragrance.

3. Long leaf orchid: epiphyte of SW Sichuan, NW to SE Yunnan, and Xizang, China (Bo Mi, Chayu, Motuo), born in forest or forest edge trees or rocks, altitude 1400-2800 meters, flowering October to January of the following year; leaves banded, 5-11, racemes with 3-7 or more flowers, sepals narrowly oblanceolate, petals falcate, lips nearly elliptic-ovate, sepals and petals green, with reddish brown veins and irregular spots, lips pale yellow to white, with reddish brown veins and spots, fragrant.

4. Tiger Head Orchid: Epiphyte, SW Guangxi, SW Sichuan, SW Guizhou, Yunnan, and SE Xizang (Chayu), trees in forests or rocks beside valleys, altitude 1100-2700 m, flowering January-April; Leaves banded, 4-6, racemes with 7-14 flowers, sepals nearly oblong, petals long and narrow oblanceolate, lips nearly elliptic, sepals and petals apple green or yellowish green, dark red spots, white to cream yellow, maroon spots and stripes, fragrant.

II. How to prevent and control orchid white silk disease?

1 When does it happen?

Orchid white silk disease, also known as white silk disease, sclerotinia disease, pathogen for semi-fungi subphylum fungi, April to May infection, June to August peak period; Sclerotia bacteria in the soil or fertilizer and not rotten residues overwinter, germination in the following year, spread in the soil, from the base of the orchid leaf invasion damage, can be transmitted by running water, irrigation water, rain sputtering and fertilization; soil acid, the most serious disease, high temperature and humid weather easy to induce disease.

2. What are the symptoms?

The disease starts from the stem of the orchid plant near the ground, initially yellow to light brown running water spots, then brown to dark brown rot, and spreads on the rhizosphere soil surface and stem base, destroying the stem and infecting young leaves and roots; the damaged parts are water-stained, rotten and soft, black, until the leaves wither, the pathogen spreads to the pseudobulb, which will lead to the death of the whole leaf cluster.

3. What are the prevention methods?

(1) Before the disease occurs: This disease is easy to occur when it is acidic (pH value is less than 5.3). Plant ash of 1/10 volume ratio can be mixed into the matrix to make the pH value about 6.5. After the new buds grow out of the ground, spray 0.05% chloramphenicol once a week, spray 2 to 3 times continuously, can prevent bacterial infection, can also spray aspirin 1500 times solution, in order to enhance the immunity of the orchid plant, prevent the invasion and spread of germs.

(2) When the disease occurs: take out the matrix stained with hyphae, disinfect the rest of the matrix with 600 times of 50% carbendazim wettable powder, sprinkle fresh plant ash, cut off the diseased roots, spray 70% thiophanate-methyl 1500 times disinfection. Cut off the diseased leaves, soak the whole plant in 10% copper sulfate solution for disinfection, or use medical chloramphenicol injection 2000 times water solution to spray the diseased plant once a day, continuously watering 3 times.

The above is the orchid varieties and got the white silk disease control methods introduced, I hope useful to everyone.