On February 23, Nature Communications published online a research paper entitled Dynamic root microbiome sustains soybean productivity under unbalanced fertilization, which was completed by Wang Ertao's research team of the Center for Excellence and Innovation in Molecular Plant Science of the Chinese Academy of Sciences and Cao Xiaofeng's team of the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences. This study, for the first time, systematically described the quantitative microbial characteristics of the entire life cycle of soybeans under different nutrient conditions. It was found that the continuous absence of nitrogen fertilizer for 41 years in black soil in Northeast China did not affect soybean yield, and revealed the mechanism of how microbial communities support soybean "increasing yield and efficiency", laying a theoretical foundation and providing technical solutions for soybean "weight loss and efficiency".
The rhizosphere microbiome is known as the "second genome" of plants and plays an important role in plant growth, development, and health. The interaction between plants and their rhizosphere microorganisms is complex and dynamic, strongly influenced by plant development and soil environment. However, traditional relative quantitative analysis methods hinder scientists' understanding of how quantitative rhizosphere microbiota dynamically responds to different soil conditions. Therefore, Wang Ertao's research team further improved the previously developed quantitative microbial analysis method and used it to describe the dynamic response characteristics of soybean rhizosphere microbial community to different fertilization treatments.
This study found through black soil experiments that did not apply nitrogen, phosphorus, or potassium fertilizer for over 40 years that long-term non application of nitrogen fertilizer did not affect soybean yield, and even resulted in an average increase of about 9%. The results of quantitative microbial community analysis indicate that long-term absence of nitrogen fertilizer shapes a unique succession pattern of rhizosphere microbial communities, while long-term absence of phosphorus fertilizer hinders the development of rhizosphere microbial communities and generally reduces their abundance. This study found that low nitrogen conditions enhanced the symbiotic relationship between soybean and rhizobia, and the low nitrogen enriched rhizosphere microbial synthesis community can promote soybean growth through various beneficial functions such as producing IAA, ACC deaminases, and dissolving inorganic phosphorus. This quantitative microbiome based study provides new insights into the dynamic assembly of rhizosphere microbial communities, highlighting their potential in replacing nitrogen fertilizers to ensure soybean yield. The above achievements deepen the understanding of how to integrate symbiotic rhizobia and beneficial rhizosphere microbial communities to prepare crop inoculants, and provide reference for optimizing soybean planting methods and reducing nitrogen fertilizer use.
The research work has been supported by the Chinese Academy of Sciences Youth Team Plan for Stable Support in Basic Research, the National Key R&D Plan, the National Natural Science Foundation of China, and the Chinese Academy of Sciences Strategic Pilot Science and Technology Project.
Paper link
Maintaining soybean yield through rhizosphere microorganisms under long-term no nitrogen fertilizer application conditions
