Key Integrated Management Techniques for Soybeans During the Flowering and Podding Stage

When soybeans enter the flowering and podding stage, vegetative growth and reproductive growth proceed together, requiring sufficient water, nutrients and light. In terms of cultivation measures, vegetative growth and reproductive growth should be coordinated to achieve many pods and many seeds. The main measures should include the following "three preventions" and strengthened management during the seed-filling and maturation stage.

The "three preventions" measures during the flowering and podding stage (1) Preventing excessive vegetative growth: when soybeans have shown 2 tillers and are flowering, use 30 grams of 15% paclobutrazol wettable powder per mu, mix with 40 kg of water, and spray to top the plants, which can shorten internodes, control top vine growth, increase flowers and preserve pods, so that pods cover the top; (2) Preventing drought and waterlogging: during the soybean flowering period, attention should be paid to summer drought, seepage and moisture retention, and in case of severe waterlogging, drain promptly to reduce waterlogging damage; (3) Controlling pests: from the end of July to mid-August is the peak outbreak period for soybean semi-looper, bean hawk moth, leaf roller, alfalfa noctuid and other pests. Pesticides with contact and stomach poison effects such as fenvalerate or cypermethrin plus dimethoate emulsion or dichlorvos can be used for control, eliminating pests at the 1st-2nd instar stage.

Strengthen management during the seed-filling and maturation stage. During this period, soybean vegetative growth gradually stops and reproductive growth is vigorous. In terms of cultivation techniques, it is necessary to preserve leaves, increase seed weight, and achieve many pods and full seeds, so management should be strengthened. Before the mid seed-filling stage, soybeans are very sensitive to moisture and require more water. If drought occurs, timely watering can increase yield; for foliar fertilizer spraying, use 5 grams of green fertilizer essence (1 packet) per mu mixed with 50 kg of water, or use a mixed solution of 1% urea and 2-3% superphosphate, and spray on the front and back of leaves after 4 p.m., with quite good results; late August is the peak damage period for soybean pod borer and pod-sucking pests. Per mu, fenitrothion or phoxim emulsion can be selected and mixed with water for spraying to kill them.

Timely and moderate harvesting. Soybeans have strict requirements for the harvest period. When the stems and pods all turn yellow, the seeds inside the pods separate from the pod walls, all bean leaves fall off, the plants make a sound when shaken by hand, and the seed moisture content drops to about 20-25%, this is the best harvest period.