The Ministry of Agriculture released the technical index of summer sowing soybean production in Huang-Huai-Hai region in 2015.

The meteorological conditions in the early stage of soybean sowing in Huanghuaihai area this year are generally good, and the temperature is the same as that throughout the year. Heavy rain occurred in the south of Huanghuai River in early June, and the soil moisture content was generally good, but the wheat harvest period was delayed by 2-3 days compared with the normal year, and the sowing date of soybean was delayed correspondingly; the rainfall in the north of Huanghuai River was less than that in the same period of the year, the temperature rose rapidly in the near future, and the soil moisture content decreased in some areas, but it was generally beneficial to accelerate the stubble of wheat and the sowing of summer soybean at the appropriate time. In order to guide the summer soybean production in Huanghuaihai area, the soybean expert guidance group of the Ministry of Agriculture and the National Agricultural Technology Extension Service Center discussed and put forward the following production technology guidance opinions.

1. Select suitable varieties

Soybean varieties with high yield, high protein, good disease resistance and suitable for mechanized harvest were selected to meet the demand of edible soybean consumption market. The heat condition in south of Huanghuai is relatively good, so varieties with relatively long growth period can be selected, such as Zhonghuang 13, Xudou 14, Xudou 16, Wandou 24, Fudou 9, Zheng 196, Shangdou 6, Yudou 29, etc. In the middle of Huanghuai River, varieties with relatively moderate maturity should be selected, such as Jidou 17, Zhonghuang 30, Wandou 28, Hedou 13, Zhonghuang 37, Zhoudou 12, Qindou 8, etc. In the north of Huanghuai River, varieties with relatively short growth period should be selected, such as Jidou 19, Handou 5, Cangdou 10, Qihuang 35, Hedou 20, Shanning 17, Zhonghuang 35, etc.

II. Sowing in time according to local conditions

The key to high yield of summer soybean in Huanghuai region is to lay a good seedling foundation and ensure full seedling strength. Advocate no-tillage machine sowing, can seize the time after wheat harvest stubble cleaning, with rotary tillage, fertilization, sowing, compaction machine sowing, improve the quality of sowing, conditional places can also be used soybean no-tillage straw mulching seeder sowing. The arid land in the north of Huanghuai River can be watered and sown to ensure a complete seedling; in the south of Huanghuai River, attention should be paid to opening "three ditches" to prevent seedling damage. According to the variety characteristics and soil fertility level, the planting density is reasonably determined. Generally, the seed amount per mu is about 6 kg, the planting row spacing is about 40 cm, the seedlings per mu are about 18,000, and the soil barren plot can be increased to more than 20,000.

III. Reasonable regulation of fertilizer and water

Soil organic matter content of most soybean fields in Huang-Huai-Hai region is relatively low. Straw should be returned to the field as much as possible to increase soil organic matter when harvesting wheat and rape. Sowing can be combined with soil testing formula fertilization, appropriate increase in phosphorus, potassium fertilizer, less nitrogen fertilizer. Generally, 45% compound fertilizer or diammonium phosphate is applied per mu for about 15 kg. Try to use the seed fertilizer integrated machine to complete sowing and fertilization at one time. At the same time, pay attention to the separation of seed fertilizer and prevent seedling burning. Before and after flowering, if the ridge is not sealed, apply special fertilizer or compound fertilizer for soybean about 10kg per mu; timely water in case of drought after flowering to promote flowering and pod formation and increase the number of seeds per plant; pay attention to watering during seed filling period to prevent seed weight from decreasing, and spray foliar fertilizer such as potassium dihydrogen phosphate and foliar treasure to prevent premature aging of plants. For the fields with vigorous growth, large population and excessive growth trend in the early stage, chemical control can be carried out before the first flowering of soybean, spraying 20ml of mepiquat amine mixed with 20kg of water per mu, or spraying 50g of 15% paclobutrazol mixed with 40- 50kg of water.

IV. Scientific use of herbicides

Soybean is very sensitive to many chemical herbicides, so herbicides should be selected scientifically and used in strict accordance with the recommended dosage in the instructions to avoid phytotoxicity or affect the growth of subsequent crops. After sowing, close weeding before seedling, generally spray 50% acetochlor 100- 130ml per mu, or 72% Dur emulsifiable concentrate plus 3- 5g 20% chlorsulfuron wettable powder mixed with 50kg water. Herbicides can be selected according to soil condition, weed species and grass age for post-emergence weeding. Quizalofop-p-ethyl, gesaphanol and fenvalerate were used to control monocotyledonous weeds, while kekuole and fomesafen were used to control dicotyledonous weeds. During the 3-leaf period of soybean, spraying 24% Kokuole 30ml +12.5% Gai Cao Neng 30- 35ml mixed with 40- 50kg water per mu can control monocotyledon and dicotyledonous weeds simultaneously.

V. Timely prevention and control of diseases and pests

Focus on the prevention and control of soybean root rot, white grubs, bean stalk black fly and other pests. 50% Duofu mixture or 50% carbendazim seed dressing with 0.5% seed amount can be used to control root rot. To prevent and control underground pests such as grubs and cutworms, phoxim and other pesticides can be used to dress seeds or kill pre-seedling baits. The control of the bean stalk black miner can be used 10-20 days after emergence of systemic chemicals. At seedling stage, imidacloprid and other pesticides are selected to control red spider, aphid, whitefly, leafhopper and other piercing pests. At middle and late stage, organophosphates, pyrethroids, high emamectin and abamectin are selected to control soybean bridgeworm, leaf roller, bean moth, locust, litura moth, pod moth, fruit borer and so on.

VI. Harvest at the right time

Soya beans are harvested immediately after ripening. During mechanical harvesting, the harvester shall be equipped with a special header for soybean, or the header height of wheat and rice harvester shall be reduced. Generally, the header height shall not exceed 17cm, so as to reduce the hitting force of the reel on the bean plant and reduce the loss of pod and grain. Correct selection and adjustment of rotation speed and clearance of threshing cylinder can reduce damaged rate of soybean seeds. If there are many weeds in the field, the large grass should be manually pulled out before harvest. Avoid dew during mechanical harvesting to prevent seeds from adhering to soil and affecting appearance quality.

(National Agricultural Technology Extension Service Center of Soybean Expert Steering Group of Ministry of Agriculture)