Causes of and Preventive Measures for Soybean Pods Without Seeds

I. Causes of Pods Without Seeds

1. Improper selection of variety or planting system. Generally speaking, late-maturing varieties with poor resistance are affected by relatively low temperatures during grain filling, which seriously affects the filling rate and thus induces the formation of pods without seeds. Continuous and alternate-year soybean planting causes a sharp decrease in the boron content of soil nutrients. Since boron is an important trace element that promotes the formation and growth of soybean pods, its deficiency induces soybean pods without seeds. At the same time, continuous and alternate-year soybean planting leads to more severe soybean diseases and pests, thereby inducing the phenomenon of pods without seeds.

2. Unreasonable cultivation measures. Seeding on stubble without tillage and late sowing will both cause the soybean root system to concentrate in the upper soil layer; when later drought occurs, pods without seeds result. Untimely seedling-stage management, soil compaction, and weak seedlings amid weeds easily induce pods without seeds. Excessive density affects the ventilation and light penetration of soybean plants, thereby weakening photosynthesis and worsening this disaster. Insufficient application of N fertilizer causes excessive vegetative growth of soybeans, with lush branches and leaves, delayed maturity with excessive greenness, and pods without seeds.

3. Poor climatic conditions. For example, if there is more rainfall during the soybean growing period, the root system is immersed in water for a long time, which weakens the root system's absorption capacity and slows plant growth, making it impossible to produce enough organic matter to fill the pods, leading to the phenomenon of soybean pods without seeds. During the soybean pod-setting and seed-filling stage, drought, high temperature, and low temperature reduce soybean photosynthesis and increase respiration, so less material is produced and more is consumed, resulting in soybean pods without seeds.

II. Preventive Countermeasures

1. Select high-quality varieties and carry out rational crop rotation. Selecting varieties that are drought-resistant and waterlogging-tolerant is the basic method to reduce the phenomenon of pods without seeds. Generally speaking, medium- and early-maturing varieties that flower early, have a relatively concentrated flowering period, and fill seeds quickly can be the first choice. Rational crop rotation can avoid one-sided and unreasonable consumption of soil nutrients, reduce disease and pest damage, and reduce the phenomenon of pods without seeds.

2. Establish rational cultivation measures. Applying an appropriate amount of N fertilizer, increasing P fertilizer application, and cultivating strong seedlings; sowing early with sufficient soil moisture and carrying out intensive cultivation during the seedling stage, timely weeding and stubble clearing; choosing a relatively suitable density for planting according to different varieties; and timely controlling diseases and pests, among other measures, can reduce the occurrence of pods without seeds.

3. Timely drought relief and drainage. Timely application of drought-relief water during the soybean pod-setting and seed-filling stage is an effective measure to prevent pods without seeds. At the same time, if there is excessive rain, field standing water should be drained in time.