Summer soybeans should be classified and managed.

Due to the urgent time for harvest and seed scrambling for summer soybeans, some farmers applied base fertilizer before sowing, and some went to the field with white seeds before applying base fertilizer. According to the investigation, at present, some soybeans have entered the branching stage, the early sowing has entered the flowering stage, some soybeans have grown more vigorously, some have appeared in the field, some are weak, the leaf yellow seedlings are thin, and the symptoms of de-fertilization and deficiency have appeared. In the face of different growth trends of summer soybeans, we should distinguish the situation and classify the management.

1. Accounting comparison. Although the growth period of summer soybean is relatively short, the general yield per mu is 100kg to 150kg. If the management is strengthened, the yield per mu can break through 150kg. If the management is given up, the yield per mu can hardly exceed 100kg, the difference in yield is at least more than 50kg, and the difference in income per mu is 150,200 yuan. However, the average fertilizer input per mu is less than 50 yuan. Therefore, it is very necessary to strengthen management.

two。 Off-fat soybeans are quickly topdressing. Although there are rhizobia in soybean that can fix part of the nitrogen in the air, but the amount is limited, fertilizer should be applied quickly to the weak soybean. First, the combination of ploughing and weeding in the flower and pod stage, topdressing 7.5 kg of urea per mu, because this is the period when the most fertilizer is needed and the most exuberant supply of fertilizer; second, if the seeds are not mixed with ammonium molybdate, 10 grams of ammonium molybdate can be used per mu and 40 kg of clear water can be sprayed; third, 1% 2% calcium superphosphate or 0.3% potassium dihydrogen phosphate solution can be sprayed twice each. Fourth, for those with symptoms of boron deficiency, 0.1%-0.2% Suele boron can be sprayed; fifth, active liquid fertilizers such as Huimanfeng or Zhuang Fuxing are sprayed with 100 milliliters per mu and 50 kg of clear water.

3. Wangchang summer soybean was chemically controlled immediately. Spraying 0.5 mg / L triacontanol solution 50 kg at the beginning of flowering could shorten the distance between upper internodes and petioles, reduce leaf area, enhance light transmittance and shorten the distance of nutrient transport, which was beneficial to the transformation of nutrients to pods. Second, spraying triiodobenzoic acid at the early flowering stage can promote branching, dwarf plant type, increase pod setting rate, and increase early maturity and yield, using 5 grams of Santian benzoic acid per mu, dissolved in proper amount of alcohol, and spraying 50 kg of water after showing yellow; or spraying 50 kg of paclobutrazol diluent with a concentration of 200 kg 250 g / L at the early flowering stage, which is beneficial to the stable growth of soybean, increase the content of chlorophyll and the accumulation of dry matter. Three can be in full bloom to the early stage of podding, with sodium bisulfite 5 grams per mu, 50 kg of water spray, can inhibit photorespiration and promote the steady growth of soybean.

Yu Hongzhang