Bacterial community composition in the rhizosphere of maize cultivars widely grown in different decades

The composition of the rhizosphere bacterial communities was compared among different maize cultivars by pyrosequencing. The cultivars were “Ye Dan 4,” “Ben Yu 9,” “Zheng Dan 958,” and “Li Min 33,” popularized in the 1980s, 1990s, 2000s, and 2010s, respectively, in Jilin Province, China. These cultivars harbored different bacterial dominant species. Significant differences were detected in the five dominant phyla, Actinobacteria, Acidobacteria, Bacteroidetes, Chloroflexi, and Planctomycetes, especially between Li Min 33 and the three other cultivars. Li Min 33 had the lowest bacterial α-diversity, which was separated from other cultivars, according to a principal component analysis and the dissimilarity test of ADONIS. The γ-Proteobacteria, and within this, the genus Rhodanobacter, were significantly more abundant around Li Min 33 than around the other maize cultivars. The canonical correlation analysis indicated that the organic matter, soil pH, soil moisture, and leaf area index were important drivers of bacterial diversity. Mantel tests showed that the cultivar was significantly correlated with the microbial community composition. These results may aid in breeding or selecting new generations of plant cultivars that have the potential to support large populations of specific microbiota.