Abstract: Soil fertility is not only an important part of soil quality, but also the foundation of land productivity. With the development of precision agriculture, the research on the relationship between soil fertility and plant root activity has become one of the hotspots in modern soil science. The purpose of this experiment was to investigate the effects of capsule seeds containing lye grass seeds and hyperabsorbent bamboo fiber microbial fertilizer on the texture and structure of different kinds of soil and the growth and development. Methylene blue method was used to measure the dynamic changes of root activity and soil moisture of lysophylline under the action mechanism of capsule seeds. The results showed that (1) capsule seeds had different effects on the water content of the three kinds of soil and the root activity of lysophylline; (2) capsule seeds could obviously increase the soil moisture content in sandy soil and loess. Under the same initial humidity, the soil moisture content of experimental group and control group was kept at the same level, reaching the highest on the 8th day. In the subsequent measurement, the soil moisture content of capsule seeds was significantly higher than that of the blank group, while the control effect of capsule seeds on soil moisture was not obvious under loam condition. (3) The root activity of lysophylline seeds was relatively improved when the three kinds of soil was treated with capsules. The results showed that capsule seeds played a certain role in controlling soil moisture and improving plant root activity.