How to prevent and control black stem disease in Gastrodia elata flower stems? Detailed explanation of causes and symptoms
Black stem disease in Gastrodia elata flower stems mainly occurs in the tubers and flower stems of sexual reproduction of Gastrodia elata, and is an important disease of sexually reproduced flower stems of Gastrodia elata. Through pathological testing, the pathogen of black stem disease in Gastrodia elata flower stems is the fungus Fusarium oxysporum. Let us take a look together at the prevention and control methods for Gastrodia elata flower stem disease!
Symptoms of Gastrodia elata flower stem disease
When flower stems are affected, it usually starts from the base near the ground, initially showing irregular dark brown or black lesions, then forming a ring-shaped black stem that expands upward. In severe cases, the diseased part constricts and breaks easily. A longitudinal cut of the diseased stem shows black-brown necrosis in the pith. Flower stems infected early die as soon as they emerge from the soil.
Conditions for the onset of Gastrodia elata flower stem disease
The pathogen Fusarium oxysporum is a soil-inhabiting fungus and can infect and cause disease at any time if conditions are suitable. At the Guizhou Gastrodia elata GAP base in Baiyi Township, Wudang District, Guiyang City, the disease occurrence period for red Gastrodia elata is April to May, and for green Gastrodia elata it is June. This disease begins shortly after the flower stems of Gastrodia elata used as sexual reproduction tubers extend out of the soil layer after being covered with soil. High temperature and high humidity favor the occurrence and development of the disease. In Longli County, Guizhou Province, this disease has also been found on wild Gastrodia elata. Using tubers infected with black rot disease as sexual reproduction seeds generally leads to this disease, and in fields with continuous cropping for many years, the disease occurs severely.
Prevention and control methods for Gastrodia elata flower stem disease
1. Choose a site with few surrounding disease occurrences as the sexual reproduction cultivation site for Gastrodia elata, and disinfect and insecticide-treat the site before use.
2. Select healthy, disease-free Gastrodia elata tubers for sexual reproduction, and do not use tubers carrying black rot disease as sexual reproduction seeds.
3. During the disease period, use 50% carbendazim wettable powder at 600-700 times dilution, or 70% mancozeb dry suspension powder at 500 times dilution, or 75% chlorothalonil wettable powder at 600 times dilution, or 60% Fangmeibao No. 2 water-soluble powder at 800-1000 times dilution and other agents for spraying or stem coating.
How much investment per mu for Gastrodia elata cultivation? Profit per mu from Gastrodia elata cultivation
For an investor in a project, before investing in a product, it is essential to make an accurate trade-off between input and output, and only invest after confirming that a certain return can be obtained. The same is true for the planting industry. What are the costs and profits of cultivating Gastrodia elata?
How much investment per mu for Gastrodia elata cultivation
To plant 1 sq m, the required Gastrodia elata seeds and Armillaria mellea spawn cost 70 yuan, fresh wooden sticks 33 kg cost about 10 yuan (including about 30 kg of thick wooden sticks with a diameter of about 4-8 cm and 3 kg of thin branches with a diameter of about 2-3 cm), clean medium-fine river sand 0.25 cubic meters costs 10 yuan (sandy soil can also be used instead of river sand; if planted outdoors, this cost can be omitted), labor and other costs are about 10 yuan, totaling about 150 yuan of investment.
Profit per mu from Gastrodia elata cultivation
The yield of Gastrodia elata per 1 sq m is generally 10 kg. Calculated at the lowest purchase price of fresh Gastrodia elata of 30-40 yuan/kg, that is, 30 yuan/kg, the output value is 300 yuan. If fresh Gastrodia elata is made into dried product (drying ratio 4-4.5:1), the current lowest market price of dried Gastrodia elata is 160 yuan/kg, and the output value can reach more than 300 yuan. Subtracting the cost of 80 yuan and labor of 80 yuan, the net income per 1 sq m is more than 150 yuan.
Then, for cultivating Gastrodia elata on 1 mu (667 sq m) of land, excluding drainage ditches and walking paths, the actual planting area is 500 sq m, and the net income can be more than 75,000 yuan.
Market forecast for Gastrodia elata cultivation
1. Gastrodia elata is a precious Chinese medicinal material and a Chinese specialty. Gastrodia elata stewed with chicken tonifies body deficiency. Regularly eating Gastrodia elata porridge and stir-frying, boiling, or stewing fresh Gastrodia elata like Chinese yam or potatoes can enhance the human body's antibodies and immune function, prevent visual impairment, eye inflammation, dry skin, and loss of mucosal secretion capacity, and can resist certain respiratory and digestive infections, and treat and reduce the harm of dizziness, vertigo, arthritis, rheumatism, waist disease, and other painful conditions.
2. Gastrodia elata can also protect the body's youthful vitality, prolong life, and prevent premature aging, and is especially effective in treating headaches. In recent years, the number of manufacturers developing Gastrodia elata foods, Gastrodia elata drinks, Gastrodia elata health products, Gastrodia elata medicinal diets, and Gastrodia elata medicines at home and abroad has been increasing day by day, requiring large quantities of supply.
Summary: Most countries in the world do not produce Gastrodia elata and can only import it from China. This has brought huge business opportunities to Gastrodia elata cultivation. It is expected that there will be no worry about sales in the next 10 years, and prices will remain stable with a slight rise.
Varieties of Gastrodia elata
1. Wu Gastrodia elata
Wu Gastrodia elata, also called iron-stem Gastrodia elata, has tall plants, reaching up to 150-200 cm in height, with gray-brown stems and white stripes. The flowers are yellow-green, and the flowering period is June to July. The fruit is prismatic or obovate-cuneate. Large tubers can reach 800 g. The rhizome is elliptical to ovate-elliptical, with relatively dense nodes, up to more than 15 cm long, and the largest single weight reaches 800 g. The water content is often within 70%, sometimes only 60%. It is mainly produced in western Guizhou, China, and Yunnan. The Gastrodia elata cultivated in Yunnan is mostly this variant.
2. Red Gastrodia elata
Red Gastrodia elata is mainly produced in the Three Gorges area. It has wide adaptability, high yield, strong reproductive capacity, and strong disease resistance, but its dry-wet ratio is large and its medicinal quality is inferior to that of Wu Gastrodia elata.
3. Green Gastrodia elata
Green Gastrodia elata plants are relatively tall, generally 1-1.5 m high. The rhizome is long-elliptical or obconical, with relatively dense nodes and many scale-like sheaths on the nodes. The largest single weight reaches 600 g, and the water content is about 70%. The stem is pale blue-green. The flowers are pale blue-green to white. The flowering period is June to July, and it is produced in various provinces and regions from Northeast to Southwest China.
4. Yellow Gastrodia elata
Yellow Gastrodia elata, also called yellow-stem Gastrodia elata, is a perennial herb with pale yellow flower stems. It grows in damp places under mountain slopes and forests and by ditches. In China, it is distributed in Hubei, Yunnan, Guizhou, Sichuan, Henan, and other places.
5. Pine Gastrodia elata
Pine Gastrodia elata is a variant of Gastrodia elata produced in northwestern Yunnan that often grows under pine and oak forests. The plant is about 1 m high. The rhizome is often spindle-shaped or cylindrical, with a water content above 90%, and the stem is yellow-white. The flowers are white or pale yellow, and the flowering period is April to May. Because of its low drying ratio, it has not been introduced for cultivation.
Although Gastrodia elata cultivation has developed for many years and the domestic market has basically developed and improved, because most countries in the world do not produce Gastrodia elata and China is the main producing area of Gastrodia elata, cultivating Gastrodia elata still has great prospects in developing foreign markets.
Cultivation techniques for Gastrodia elata
This is my first time planting Gastrodia elata. I need detailed techniques for Gastrodia elata cultivation and management. Please send them to my email 0824****. Thank you!!Name: Xiang Guangliang Unit: farmer Contact phone: 2009-01-30
Expert answer
Comrade Xiang Guangliang: Hello. Gastrodia elata is the tuber of Gastrodia elata, a perennial parasitic herb in the orchid family. It has the effects of calming wind and soothing the liver, and mainly treats liver-wind dizziness, head wind and headache, limb numbness, infantile convulsions, and so on. Modern research shows that it has effects such as lowering blood pressure, relieving pain, resisting rheumatism, and resisting convulsions. The entire Gastrodia elata plant has no roots and no green leaves, only aboveground flower stems and underground tubers. The Gastrodia elata tuber is fleshy and thick, oblong or elliptical, with pale yellow skin, uniform rings, membranous scales at the nodes, and mixed buds at maturity. Due to different developmental stages, underground tubers are divided by morphology into arrow Gastrodia elata, white Gastrodia elata, and rice Gastrodia elata. Arrow Gastrodia elata is a mature tuber with a terminal red mixed bud, generally 6-12 cm long, 3-7 cm in diameter, and 100-200 g in weight, with the largest over 500 g. After overwintering, it can bolt and flower, and its stem (1-1.5 m) resembles an arrow, hence the name. White Gastrodia elata is also a tuber, 2-11 cm long, 2-3.5 cm in diameter, and about 20 g in average weight; the terminal bud is not obvious, has no flower spike primordium, and only has a round growing cone. Rice Gastrodia elata is similar in morphology to white Gastrodia elata, differing only in size. Small white Gastrodia elata less than 2 cm long is called rice Gastrodia elata. Both white Gastrodia elata and rice Gastrodia elata can be used as seed Gastrodia elata. I. Cultivation techniques for Gastrodia elata (1) Asexual cultivation techniques Using Gastrodia elata tubers for cultivation is called asexual cultivation. With this method, the cultivation cycle is short and results are quick. 1. Site selection For cultivating Gastrodia elata in low-altitude areas, the main problem to solve is the effect of high summer temperatures on Gastrodia elata growth. Therefore, tree shade, shaded ground behind buildings, and indoor cultivation should be used for Gastrodia elata. Where conditions permit, it is best to use a basement. Cultivating Gastrodia elata in a basement requires no cooling in summer and no freeze protection in winter, making it the most ideal place for cultivating Gastrodia elata. 2. Selection of seed Gastrodia elata The quality of seed Gastrodia elata directly affects the survival rate and yield of Gastrodia elata. Choose white Gastrodia elata (10-20 g) and rice Gastrodia elata with complete individual development, no damage, and no pests or diseases as seeds. 3. Cultivation time Cultivating during the dormant period of Gastrodia elata can achieve high yield. Winter is cold, and Gastrodia elata is easily damaged by freezing during cultivation, and cold protection work is also troublesome, so it is suitable to cultivate after thawing in late March, called spring planting. Although Gastrodia elata does not sprout after planting, Armillaria mellea can still grow. Only when a relationship with Armillaria mellea is established before Gastrodia elata sprouts can Gastrodia elata obtain sufficient nutrition. Therefore, Gastrodia elata cultivation should be early rather than late. If Gastrodia elata is cultivated indoors or in a site with cold protection conditions, it can also be planted while harvesting at the end of October, called winter planting. 4. Cultivation depth and seed quantity Indoors or in places with tree shade and moist soil, the soil cover after planting Gastrodia elata should not exceed 10 cm; in places with higher temperatures and little rain, the soil cover after planting can be appropriately increased, generally not exceeding 15 cm, with about 500 g of seeds used per sq m. 5. Cultivation methods 1) Pit cultivation. Generally, the pit is 1.2 m long, 0.7 m wide, and 35 cm deep. First spread a 5 cm thick layer of sand at the bottom of the pit, then place cut logs and fungal material on the sand with 3-5 cm spacing, fill the gaps with mixed sand (sand and sawdust mixed at a volume ratio of 2:1), in a half-buried state, then plant seed Gastrodia elata near the fungal material at 10-15 cm spacing, paying attention to head-to-tail connection. Small rice Gastrodia elata can simply be scattered around the fungal material. After planting, cover with a thin layer of sand to cover the cut logs, then plant a second layer by the above method, and finally cover with 10-15 cm of sand. The bed should be higher than the ground, and a layer of leaves and other materials should be added to keep warm and moist. 2) Bed (ridge) cultivation. Generally, the bed is 0.7 m wide and 35 cm deep, with unlimited length, and the planting method is the same as pit cultivation. 3) Fungal bed cultivation. If there is 1 layer of fungal material, the soil cover can be removed, the fungal material is not moved, and holes are dug near the fungal material to plant seed Gastrodia elata by the above method; if there are 2 layers, the upper layer of fungal material should be removed, seed Gastrodia elata planted in the lower layer; then the upper layer of fungal material put back, and seed Gastrodia elata planted again. 4) Indoor cultivation. Sand pile cultivation can be used (build a frame of 70 cm x 120 cm with bricks), or bamboo baskets and wooden boxes can be used, with the same method as above. As long as temperature, humidity, and ventilation can be well controlled, high yield can also be obtained. (2) Sexual cultivation techniques Using seeds for cultivation is called sexual cultivation. This is currently the most advanced cultivation technique and can produce first-generation seed Gastrodia elata with strong growth vigor and strong stress resistance, thereby greatly increasing Gastrodia elata yield. 1. Preparatory work For each sq m, 20 fresh broadleaf tree cut logs with a diameter of 5-10 cm and a length of 40 cm are needed (oak is preferable). Cut fish-scale notches on both sides of the cut logs every 5 cm, and cultivate them with wet sand for later use. Dry oak leaves or chestnut leaves 2 kg should be soaked in water before cultivation. 1 cubic meter of river sand and 1 sack of sawdust (forest humus soil can also be used) can cultivate 5 sq m. River sand and sawdust (or humus soil) are mixed at a volume ratio of 2:1, with a water content of 50% (can form a ball when held by hand). 2. Cultivation time and operation method April to May. Gastrodia elata seeds obtained through artificial sexual hybridization are as small as ash. When sowing, germination-promoting fungi are needed for culture to make them germinate. After about two months of culture and germination, when tiny protocorms can be seen with the naked eye, they can be transferred to Armillaria mellea material for continued culture. The seed Gastrodia elata cultivated in this way is the original seed. After being cultured with germination-promoting fungi for a period of time, it is transferred to Armillaria mellea material for culture. The operation method is: in June to July, first spread 5 cm thick pure sand on the ground (spread 10 cm on cement ground), then spread 2 cm thick leaves, then take 1/2 of 1 portion of seeds and scatter them evenly, then place 1 cut log every 5 cm, place 3-4 fungal branches on one side of each cut log, and fill and cover with mixed sand, then plant the second layer by the above method, and finally cover with 10 cm of mixed sand. In addition, fungal material and cut logs can also be placed alternately for cultivation. (3) Field management 1. Cold protection For winter-planted Gastrodia elata overwintering in the field, in order to prevent freezing damage, it must be covered with more than 30 cm of sand or leaves in November, and the covering removed after the beginning of spring the following year. 2. Temperature regulation After the beginning of spring, in order to speed up Gastrodia elata growth, plastic film should be covered in time to increase temperature. After the temperature rises in mid-May, the plastic film must be removed, and then covered again in late September to extend the Gastrodia elata growth period. During high summer temperatures, grass should be covered or a shade shed built to keep ground temperature below 28 degrees C. During the Gastrodia elata growth period, there is no need to pull weeds or apply additional fertilizer. 3. Drought prevention and drainage During spring drought, water and loosen the soil in time so that the water content of the sandy soil is about 40%. In June to August in summer, Gastrodia elata grows vigorously and water demand increases, so the water content of the sandy soil can reach 50%-60%. During the peak period of Gastrodia elata expansion, potato water can be used (potatoes mashed and soaked in water, then filtered), sprayed once every 5 days. In the rainy season, attention should be paid to drainage to prevent water accumulation from causing Gastrodia elata rot. After late September, the temperature gradually decreases, and Gastrodia elata growth slows. However, Armillaria mellea can still grow at 6 degrees C. At this time, with high moisture, Armillaria mellea grows vigorously and can infect new Gastrodia elata. Under such environmental conditions, it is not conducive to Gastrodia elata growth but only to Armillaria mellea growth, thereby causing Armillaria mellea to further penetrate into the inner layers of Gastrodia elata and causing tuber rot. Therefore, special attention should be paid to preventing waterlogging in September to October. 4. Pest and disease control Like other plants, Gastrodia elata also suffers from pests and diseases during growth and development. 1) Diseases. The main harm is infection by miscellaneous fungi, which in severe cases can cause Gastrodia elata tuber rot. Miscellaneous fungal hyphae are green, yellow, white, and other colors. However, they generally cannot produce rhizomorphs and are easy to identify. When miscellaneous fungi are found, they must be removed. Prevention and control methods: choose fungal material with vigorous Armillaria mellea rhizomorphs and no miscellaneous fungi; when culturing fungal material, increase the amount of spawn used to create a growth advantage for Armillaria mellea so as to inhibit miscellaneous fungi; the sand and soil for cultivating Gastrodia elata must be clean and replaced once when harvesting and replanting; fungal material should be completely replaced after 2-3 years of use; watering should be even, and attention should be paid to regulating temperature and humidity; before planting, treat the cultivation site with lime or other fungicides and insecticides. 2) Pests. For mole crickets, mix 250 g of dimehypo aqueous solution, 25 kg of roasted fragrant wheat bran, and 7.5 L of water, then scatter on the ground surface in the evening to trap and kill. For grubs, before planting, use 1.5-2.5 kg of carbofuran applied at the hills. When conditions permit, black light lamps can be set up to trap and kill adults (scarab beetles). II. Harvesting, storage, and processing of Gastrodia elata (1) Harvesting. Harvesting Gastrodia elata during the dormant period gives high medicinal efficacy. Therefore, asexual cultivation should be harvested at the end of October of the same year or in late March of the following year (can be planted while harvesting); sexual cultivation is generally harvested in the autumn of the second year. If cold protection conditions in winter are good, it can be harvested in spring. This can reduce intermediate steps, and after dormancy the tuber naturally separates from the vegetative propagation stem, reducing damage during harvest. Gastrodia elata tubers will rot if planted after being bruised, so during harvest they should be handled gently. After harvest, arrow Gastrodia elata is processed for medicinal use, and white Gastrodia elata and rice Gastrodia elata are used as seeds. Asexual cultivation generally produces 7.5-12.5 kg of fresh Gastrodia elata per sq m, with arrow Gastrodia elata accounting for 70%, and white Gastrodia elata and rice Gastrodia elata accounting for 30%; sexual cultivation generally produces 10 kg per sq m, with arrow Gastrodia elata accounting for 30%, and white Gastrodia elata and rice Gastrodia elata accounting for 70%. (2) Storage. Select high-quality seed Gastrodia elata, air-dry for 1-2 days, then place in wooden boxes or pits, arranging layer by layer, with a little distance between seed Gastrodia elata, not pressed tightly together, separated between layers with sand, arranging 4-5 layers. Control the temperature at 1 degrees C-5 degrees C, and do not let the temperature fluctuate too much, so as not to affect seed Gastrodia elata dormancy; control humidity at 25%-30%, as excessive humidity will cause seed Gastrodia elata to rot. During storage, frequently observe temperature and humidity. (3) Processing. First grade by weight: those above 150 g are grade 1, 75-150 g are grade 2, and below 75 g are grade 3. Then wash with water and steam or boil. When the quantity is small, steam in a pot; when the quantity is large, boil in water to kill the lysozyme in the Gastrodia elata body. After the water boils, pour Gastrodia elata into the water according to different grades, and add a small amount of alum (200 g per 10 kg of Gastrodia elata). Grade 1 is boiled for 10-15 minutes, grade 2 for 7-10 minutes, and grade 3 for 5-9 minutes. When looking from a dark place toward a bright place there is no black center, or when one Gastrodia elata is broken open for inspection and the white center accounts for only 1/5 of the Gastrodia elata diameter, it can be taken out of the pot. Boiling too soft will affect the drying ratio and also affect medicinal efficacy. After Gastrodia elata is boiled, place it in a fumigation room and fumigate with sulfur for 20-30 minutes. The method is: use 20% sulfur plus 80% yellow mud, mix evenly with water, make into egg shapes and place over charcoal fire. After fumigation, Gastrodia elata has a clean white color, good quality, and can prevent insect damage. Then dry by baking or sun-drying. If there is gas swelling inside the Gastrodia elata body, use a bamboo needle to release the gas. When it is 70%-80% dry, press it flat with hands or a small board, then dry until completely dry. Generally, 5 kg of fresh Gastrodia elata can produce 1 kg of dried product. The above content is for reference only.