Detailed Explanation of Buckwheat Production Techniques: Key Points for High-Yield Cultivation

Buckwheat, also known as black wheat, flower wheat or triangular wheat, belongs to the Polygonaceae family. Buckwheat grains have high nutritional value, containing 62% starch, 12.29% protein, and 2.4% fat, and are also rich in mineral elements such as iron, phosphorus and calcium, as well as vitamins B1, B2, B6 and vitamin P. Modern medicine has proven that tartary buckwheat is rich in a special substance -- rutin, which is an effective traditional Chinese medicine for treating high blood pressure, diabetes, coronary heart disease, meningitis and other diseases. Therefore, buckwheat is not only a food crop with high nutritional value, but also an important raw material for the food industry and pharmaceutical industry. Every part of buckwheat is useful: buckwheat stems and leaves and processing by-products are good feed; buckwheat hulls used to make pillows can nourish the spirit and benefit the eyes; buckwheat straw used for bedding can repel mosquitoes and insects. In addition, because buckwheat has wide adaptability, simple cultivation techniques, low production cost, and flexible crop rotation arrangements, it does not compete with major crops for land, so it can increase the multiple cropping index and also serve as a disaster-relief crop in famine years. At the same time, because the flowering period of buckwheat is staggered from most crops in nature, it is also a major nectar-source crop.
　　
Cultivation Techniques for Buckwheat
1. Variety selection: There are currently no newly bred varieties of buckwheat; generally, the best varieties are selected from farmer varieties using the plant selection method. Buckwheat is divided into tartary buckwheat and common buckwheat. Tartary buckwheat varieties include our province's Fenghuang tartary buckwheat, Zhongfang County's Tangwan tartary buckwheat, Jiangxi Jiujiang tartary buckwheat and Guizhou tartary buckwheat; common buckwheat includes 96-1 from Dingxi region of Gansu Province, “Dahonghua” from Zhenba County of Shaanxi Province, and Japan's “Dalibuckwheat”. These varieties have all performed relatively well when planted in our province, with an average yield of 70-75 kg per mu.
2. Crop rotation: First, buckwheat is planted after early rice or middle rice is harvested, and after buckwheat is harvested, rapeseed or wheat is planted in a three-crop system. Second, after corn is harvested on dry land, one season of buckwheat is planted, followed by one season of vegetable crops, and then corn is planted again the following year. There is also spring planting of common buckwheat on dry land as green fodder.
3. Land preparation: Prepare the land finely, loosen it evenly, eliminate weeds, maintain suitable soil moisture, and create favorable environmental conditions suitable for buckwheat growth and development, so as to strive for full stands and strong seedlings. Buckwheat fields are generally divided into plots 3-5 m wide, and larger fields should also have cross ditches opened for easy irrigation and drainage.
4. Sowing: Improving sowing quality is an important step in ensuring a full stand of buckwheat. Buckwheat seeds have a relatively short lifespan and lose viability after one year. The seeds vary greatly in size, the seed coat is relatively thick, and the degree of maturity is uneven. These factors all affect the germination rate of the seeds and the uniformity of emergence. Therefore, before sowing, winnowing and screening should be carried out, and large, plump and fresh seeds should be selected for sowing, which can improve the germination rate and germination vigor. Seeds whose inner seed coat is green have a high germination rate and viability; if it has turned yellow, the germination rate and viability decrease. If seeds are soaked in warm water at 30-40 degrees C for 10 minutes, or sun-dried before sowing, the germination rate of the seeds can also be improved. Earlier emergence has a good effect on increasing yield. If spring buckwheat is sown too early, the seedlings often suffer damage from late frost; if autumn buckwheat is sown too late, the later growth stage is likely to encounter early frost, and the yield will be relatively low. Therefore, the sowing period for buckwheat should follow the principle of “sow spring buckwheat after frost, harvest autumn buckwheat before frost”; autumn buckwheat in our county is generally sown in mid to late August. Only suitable density can ensure the desired yield. Generally, density should be controlled on fertile land, with 40,000-60,000 plants per mu being suitable; on medium-fertility land, density should be appropriately increased, with 60,000-100,000 plants per mu being suitable; on poor land, density must be increased, with 110,000-160,000 plants per mu being suitable. Sowing should not be too deep, and covering with soil to about 3 cm is suitable. Clay soil should be shallower, and sandy soil slightly deeper. The sowing methods for buckwheat include drilling, dibbling and broadcasting, with drilling generally adopted. This is because with drilling, the seeds are distributed evenly, the soil cover is uniform, the seedlings emerge neatly, and field management is convenient. The row spacing for drilling is suitably about 40 cm, and the sowing rate is generally 2-3 kg per mu for broadcasting; larger seeds should be sown somewhat more, and smaller seeds appropriately less.
5. Fertilization: The growth period of buckwheat is relatively short, so heavy application of base fertilizer should be the main approach. Apply sufficient base fertilizer, apply topdressing early, and apply phosphorus and potassium fertilizer appropriately. For base fertilizer, it is best to plow farmyard manure and plant ash into the soil during plowing, and then apply additional fertilizer rich in phosphorus and potassium at sowing, such as plant ash and chicken manure, generally 1000-1500 kg per mu. After emergence, combine with the first and second intertillage to apply diluted human waste or superphosphate. If the base fertilizer is insufficient, a small amount of quick-acting nitrogen fertilizer can be applied as topdressing to promote robust seedling development. Nitrogen fertilizer should not be applied too much or too late, so as to avoid delaying flowering and fruiting and causing lodging in the later stage. Applying phosphorus fertilizer after the flowering stage of buckwheat, or spraying trace element fertilizers such as boron, molybdenum and manganese on the leaves, has an obvious yield-increasing effect.
6. Management: After sowing, if the soil surface becomes compacted due to rainfall, it is best to carry out a shallow intertillage to break the surface crust and facilitate seedling emergence. After that, carry out 1-2 intertillage operations according to the occurrence of weeds in the field. Intertillage and weeding must be completed before flowering, when the seedlings are about 30 cm tall; after that, intertillage should no longer be carried out to avoid damaging the plants. Generally, the first intertillage is carried out when the seedlings are 7-10 cm tall, and thinning should be done appropriately at the same time, removing relatively dense and weak seedlings so that the plants are not crowded; after 6-7 days, a second intertillage is carried out, combined with hilling to promote the development of the adventitious root system of buckwheat. Buckwheat is a crop with relatively high water requirements, and must be watered when drought occurs during the flowering and fruiting stage. Generally, a shallow watering is given around the booting stage, which is beneficial to root development and increases the proportion of flowering; a second watering at the full flowering stage of buckwheat can increase the seed-setting rate. In rainy weather or low-lying land, in addition to attention to making beds and watering, attention should also be paid to deep ditch drainage to prevent waterlogging, so as to avoid root rot caused by water accumulation. During flowering and grain filling, buckwheat should be protected from frost. Therefore, some places use the method of watering before frost, and some use the method of smoking to prevent frost, both of which have certain effects. Buckwheat is a cross-pollinated crop, and pollen dispersal mainly depends on insects, especially bees. Under poor climatic conditions and when bees are not kept, artificial supplementary pollination can increase the seed-setting rate of buckwheat, and where conditions permit, it can be carried out at around 1 p.m. during the full flowering stage. The method is to use a relatively soft cloth with ropes tied to both ends, pulled by two people, letting the cloth brush along the top of the plants and gently shaking the plants, which can play a role in supplementary pollination. Artificial supplementary pollination is carried out once every 2-3 days, and can be done 2-3 times, increasing yield by 10%-20%. Keeping bees can also be used to assist buckwheat pollination, and this method is more effective than artificial supplementary pollination. During the buckwheat flowering season, about one box of bees should be placed per 2000 sq m, which can greatly increase the pollination rate of buckwheat.
7. Pest and disease control: The pests and diseases harming buckwheat include ring spot disease, brown spot disease and white mold disease. Because buckwheat mainly relies on insects for pollination, spraying too much pesticide will kill a large number of beneficial insects. Therefore, the control of buckwheat pests and diseases mainly adopts comprehensive agricultural control measures, and low-toxicity pesticides are used when necessary.
8. Harvest: The flowering period of buckwheat is relatively long, generally requiring about 30 days. Its flower stalks are small, and the seeds mature very unevenly; often one part has already matured while another part is still flowering, and mature seeds fall off easily, so timely harvest is extremely important. Generally, when 2/3 of the seeds on the whole plant are dark brown, it can be harvested. Harvesting too early will reduce quality because of mixing with a large number of immature seeds; delaying harvest will cause a large number of seeds to fall off and reduce yield. When harvesting, attention should be paid to cutting and handling gently to reduce seed shattering. Buckwheat seeds reserved for planting are best when deep black and small in grain size. Autumn buckwheat reserved for seed use must be harvested before frost. Seeds reserved for planting should be thoroughly sun-dried and stored in a ventilated place.