| Description |
Plant growth has acknowledged to be affected by soil heterogeneity at large scales. However, effects and mechanisms of small-scale soil heterogeneity on crop growth have been rarely reported. In this study, a clear boundary existed in the field, which divided phenotypes of fava beans into two distinct groups (Big vs Little). Soil concentration of As, B, Co, Cr, Cu, Pb, Sr, Zn, Ni, Cd and pH significantly differed in the rhizosphere of fava beans in the two adjacent rows, which were located on either side of the boundary with the row-spacing is 30 cm. Random Forest analysis demonstrated these differentiated soil properties substantially influenced fava beans growth (length and biomass). Metagenomics sequencing illustrated rhizosphere eukaryotes were sensitively shaped by phenotypes of fava beans. A total of 20 metabolites, including coniferyl alcohol, jasmonic acid, resveratrol, and L-aspartic acid, etc. were found to be significantly correlated with fava beans growth. These metabolites were significantly enriched in nucleotide metabolism, pyrimidine metabolism, purine metabolism, biosynthesis of plant secondary metabolites, lysine biosynthesis, etc. 15 functional pathways. Furthermore, 11 microbial genera were measured as involving in these functional pathways, differently enriched between the two groups and significantly correlated with fava beans growth. Overall, the heterogeneity of soil elements at small-scale altered rhizosphere differential microorganisms and metabolites, which functionally influenced fava beans growth and tolerance to environmental stress. Small-scale soil heterogeneity needs to be notably addressed to optimize field managements for increasing crop production, which is crucial for the survival and sustainable development of humanity |
