What are the key points of high-efficiency cultivation techniques for Pinellia ternata?

Pinellia ternata, a plant of the genus Pinellia in the Araceae family, is a commonly used traditional Chinese medicinal herb. Its dried tubers are used as medicine, mainly to treat cough, asthma with excessive phlegm, nausea and vomiting, and other conditions. In recent years, it has been found that Pinellia protein has anti-early-pregnancy and anti-tumor effects, making it one of the scarce Chinese medicinal herbs for many years. Xihe County, Gansu Province is a suitable growing area for Pinellia ternata. The Pinellia produced there is white in color, high in starch, and good in shape, and is well received by users, who call it Xi Pinellia. After the successful transition from wild cultivation to artificial planting of Pinellia in Xihe County, growing Pinellia became one of the main sources for local people to escape poverty and increase economic income. However, long-term reliance on digging up wild Pinellia for seed caused wild resources to be on the verge of exhaustion, seed prices to remain high, diseases to worsen year by year, costs to surge, benefits to decline, and planting area to shrink sharply.

In response to the problems existing in Xi Pinellia production, researchers from the Institute of Economic Crops of the Gansu Academy of Agricultural Sciences carried out experimental research in three aspects: high-efficiency cultivation techniques, disease control, and artificial propagation of Xi Pinellia seed tubers. They set up 13 various experiments in succession and achieved the expected results.

I. Technical regulations for high-efficiency cultivation of Pinellia ternata

Experiments show that winter and spring are suitable sowing periods for Pinellia ternata, with similar yields; sowing depth has an enormous impact on yield. Appropriate shallow sowing can increase yield by about 50%. With plastic film mulching, seedlings emerge 20 days earlier than in open field, the yield of fresh tubers is 535 kg per mu, an increase of 82.3 kg compared with open field, and net output value increases by 478.2 yuan; when cultivated under a small plastic arched shed before emergence, seedlings emerge 15 days earlier, the yield of fresh tubers is 1083 kg per mu, an increase of 202.1 kg compared with open field, and net output value increases by 1482 yuan per mu; after emergence (June 12), covering with 60-65% shade netting increases yield by 25.3% per mu, and covering with straw after emergence increases yield by 15.5% per mu compared with the control. Planting density has a direct impact on Pinellia yield and planting benefits.

The high-yield and high-efficiency optimized cultivation model for Xi Pinellia is: on medium or higher fertility soil, apply 6.4-7.7 kg of pure nitrogen, 6 kg of phosphorus oxide, and 6 kg of potassium oxide per mu, with a sowing rate of 200-250 kg per mu (diameter 0.8-1.2 cm), or 252-295 grains per sq m. During the growth period, the number of petioles per mu reaches 500,000-550,000. Verified by production demonstrations, the average yield is 490.4 kg per mu, an increase of 40.4 kg compared with the control average yield of 450 kg per mu.

II. Disease control

The main diseases of Pinellia ternata are tuber rot, anthracnose, and ring rot. Tuber rot is caused by combined infection of diseases and pests. Using DuPont Fuxing and Mix No. 3 (fungicide and insecticide) has a certain control effect, with a control efficacy of 58-49% at the peak incidence period. Control measures for soil-borne diseases of Pinellia ternata: 1. Crop rotation, replant after an interval of more than 5 years; 2. Establish seed propagation bases in disease-free areas; 3. Spray manganese fertilizer and strengthen management; 4. Soil treatment: mix 1 kg of isofenphos-methyl into toxic soil or dilute with 25 kg of water, spray evenly on the ground, and turn into the soil during land preparation; 5. Chemical seedtreatment: soak seeds in 6000-fold DuPont Fuxing solution for 10 hours, then air-dry and sow; 6. Foliar spraying: near the onset period (late May or early June), spray leaves with 400-fold mancozeb solution once every 7-10 days for 3-4 consecutive sprays.

III. Suitable areas and seed tuber standards for artificial propagation of Pinellia ternata

Pinellia ternata mainly uses seeds, bulbils, and tubers as propagation materials. Seed propagation can overcome variety degeneration caused by long-term asexual propagation; tissue culture rapid propagation is conducive to purification and selection of superior Pinellia varieties and has important practical value. It can multiply 5 times a year. Adding ginseng powder and fritillary powder to the rooting medium is beneficial for rooting, and the transplanting survival rate is high. In production, tubers and bulbils are used for propagation. Through film mulching before seedling emergence, straw mulching, and shading with shade netting after emergence, an average of 3.7-4.1 bulbils are formed per plant, an increase of 27.6-41.1% compared with open-field propagation; for self-sown seedling propagation, planting corn after Pinellia harvest allows the omitted Pinellia tubers and bulbils in the field to sprout and emerge again, and 40-50 kg can be harvested per mu.

Off-site propagation seed has a yield similar to wild seed, and artificial propagation can completely replace wild seed. Propagating stock seed off-site and propagating production seed locally is relatively economical and reasonable.

Seed tuber diameter directly affects Pinellia yield and planting benefits. Medium-sized seed with a diameter of 0.8-1.2 cm has the highest net yield, so the standard for Pinellia seed tuber diameter is set at 0.8-1.2 cm.

IV. Artificial propagation of Pinellia seed tubers

Pinellia ternata is a naturally cross-pollinated crop. Artificial propagation, purification, and selection of superior plants are carried out through a two-level breeding system of stock seed and production seed. Stock seed is propagated by seed, establishing a seedling stock seed field, and using tissue culture technology for purification and expanded propagation. In production, bulbils and tubers are used for propagation.