Detailed Explanation of Key Techniques for Field Cultivation of Cordyceps sinensis
Cordyceps sinensis, also known as cordyceps, is a precious tonic medicinal herb commonly used among the Chinese people. Its nutritional components are higher than those of ginseng. It can be used as medicine and also eaten, and is a superior delicacy with very high nutritional value. Cordyceps sinensis can enhance the body's immunity, nourish the lungs and kidneys, and has a significant inhibitory effect on lung cancer, liver cancer, and others. Clinically, it has therapeutic effects on chronic cough due to lung deficiency, asthma, hemoptysis from pulmonary tuberculosis, night sweats, soreness and weakness of the waist and knees due to kidney deficiency, impotence and seminal emission, neurasthenia, and decreased red blood cells after chemotherapy and radiotherapy.
Morphological characteristics:
Cordyceps sinensis is formed by the connection of the insect body and the fungus stroma, with a total length of 9-12 cm. The insect body resembles a three-times-molted old silkworm, about 3-6 cm long and about 0.4-0.7 cm thick. The surface is dark yellow and rough, with many transverse wrinkles on the back, and 8 pairs of feet on the ventral surface, of which the 4 pairs located in the middle of the insect body are clearly visible.
The cross-section is solid inside, white, slightly yellowish, with a dark yellow periphery. The fungus stroma grows from the head of the insect body, is club-shaped and curved, and is slightly swollen at the upper part. The surface is grayish brown or dark brown, up to 4-8 cm long, about 0.3 cm in diameter. When broken, the interior is hollow and powdery white. The odor is slight, and the taste is bland. Those with bright yellow insect body color, plump and fat body, yellow-white cross-section, and short fungus stroma are considered good.
Techniques for field cultivation of Cordyceps sinensis
1. Select seed stems. Cordyceps sinensis does not reproduce by seeds; rhizomes are selected as seedlings. Stems that are thick and plump among non-flowering plants, with long internodes and little root damage, should be selected. The seed stems should be at least 5 to 6 cm long, preferably 15 to 20 cm. Generally, planting can be done in all four seasons. However, to ensure the survival rate, it is best to choose spring, when the seed stems have just sprouted and transplanting is easy for survival.
2. Land preparation and base fertilizer application. Choose a field with convenient irrigation, fully prepare the land, and then make raised beds. Apply base fertilizer during land preparation. Per mu, apply 3000 to 5000 kg of farmyard manure, 50 kg of compound fertilizer, 50 kg of superphosphate, 15 to 20 kg of potash fertilizer or 100 kg of plant ash.
3. Ditching and sowing. On the raised beds in the field, open a longitudinal ditch every 35 cm, with a depth generally suitable at 8 to 10 cm. In the ditch, plant one stem of Cordyceps sinensis every 7 to 10 cm. After placing them, carefully cover the planted stems with fine soil, and do not let the seed stems be exposed on the soil surface.
4. Weeding and irrigation. Cordyceps sinensis is easily crowded out by weeds. Therefore, after sowing, immediately spray the field once with glyphosate and acetochlor, and thereafter apply acetochlor once every 20 days. After Cordyceps sinensis covers the entire field, switch to manual weeding. Cordyceps sinensis likes moisture but fears waterlogging. For irrigation, furrow irrigation and sprinkler irrigation are best, and flooding irrigation should not be used. Ensure that the bed surface of the raised bed is free of water while the bed furrows retain accumulated water.
5. Fertilization management. After sowing, starting from the completion of seedling emergence, apply fertilizer once every 10 to 15 days, each time with 30% human feces and urine. In the peak growth season from May to June, switch to 50% human manure fertilizer. Apply 1500 to 2000 kg per mu each time, and add about 10 kg of urea per mu for the last application. After Cordyceps sinensis closes its rows, no more inter-row fertilization is needed, but foliar fertilization can be carried out by spraying with 0.1% to 0.2% monopotassium phosphate, applying about 50 kg per mu of water-fertilizer mixed solution. After Cordyceps sinensis grows larger, in order to direct nutrients to the growth of underground stems, the flower buds should be removed in time.
6. Harvesting. The leaves and underground stems of Cordyceps sinensis are both edible. However, in the first year of planting, leaves should not be harvested. From February to April of the second year, young leaves and underground stems can be harvested. May and June are the peak growth season for Cordyceps sinensis, so harvesting is not suitable. From July to September, young leaves can be harvested. From September of the same year to March or April of the following year, underground stems can be harvested.
7. Disease control. Cordyceps sinensis generally has no insect pests. Common diseases include southern blight, root rot, purple spot, and leaf spot. Generally, diseases are rare in the first 1 to 2 years of cultivation, and the above diseases only appear successively from the 3rd year. Diseased plants should be dug out promptly together with roots and soil, and pentachloronitrobenzene should be sprinkled into the holes for disinfection. Then spray the field with 1:1:100 Bordeaux mixture or 25% triadimefon wettable powder 1000-fold solution, or spray with 50% thiophanate and 50% thiram 250 to 300-fold solution.