As early as the early 1930s, when the research on plant growth hormone was still in the primary stage, Chen Huagui first discovered that the elongation and bending of crop root hairs before being infected by rhizobia were related to the secretion of auxin by rhizobia. In the late 1930s, he made a comparative study on the morphological development of high-efficiency rhizobia and low-efficiency rhizobia, and clarified an important aspect of the effective mechanism of nitrogen fixation. The paper was published in the Journal of the Royal Society, and his conclusions at that time are still quoted by Steiner and others' Microbial World, Bejason's papers and related textbooks in the 1970s. In 1974, Quespeer spoke highly of the significance of his research results.

Another contribution of Chen Huagui to the study of nitrogen fixation in * * * is that in 194 1 year, together with Xu Mingguang and Steven Zhang, he discovered for the first time that rhizobia of Chinese milk vetch and nitrogen fixation of Chinese milk vetch were independent "interconnected races". This paper was published in the American Journal of Soil Science. This discovery not only enriches the specific knowledge of nodulation and nitrogen fixation of rhizobia and host plants, but also has important practical significance for the production and application of rhizobia agent of Chinese milk vetch.

In 1950s, the research group led by him continued to study the relationship between rhizobia of Astragalus sinicus from many aspects. In the early 1960s, excellent strains of rhizobia isolated from Astragalus sinicus were directly involved in the construction of bacterial fertilizer plants, the production of rhizobia from Astragalus sinicus and the experiment, demonstration and popularization of large-scale application, which provided an important technical means for expanding the planting area of green manure of Astragalus sinicus in rice fields in southern China and developing double-cropping rice. In the late 1970s, he led his colleagues to open up a new field of nitrogen fixation research, cultivate and guide new forces, and carried out molecular genetics research on nitrogen fixation.

Chen Huagui has always held a strict scientific attitude towards the application and promotion of bacterial fertilizer. In the upsurge of blind production and popularization of bacterial manure in the late 1950s, He and his research group neither echoed nor contributed to it. In the social atmosphere of basically denying bacterial fertilizer, he promptly called for the scientific development of rhizobia (People's Daily 1964 May,19) and insisted on research and application promotion, thus promoting the production and application of rhizobia for Chinese milk vetch in the 1960s and 1970s and expanding the planting area of Chinese milk vetch in rice fields. According to the actual effect of peanut rhizobia, on his initiative, the academic conference of biological nitrogen fixation of Hubei Soil Society 1979 suggested to the Ministry of Agriculture to strengthen the popularization and application of peanut rhizobia.