Comparison of Rhizosphere Microbiomes Between Domesticated and Wild Wheat in a Typical Agricultural Field: Insights into Microbial Community Structure and Functional Shifts

While the differences between domesticated crops and their wild relatives have been extensively studied, less is known about their rhizosphere microbiomes, which hold potential for breeding stress-resistant traits. We compared the rhizosphere microbiomes of domesticated wheat (Triticum aestivum L.) and its wild ancestor (Triticum turgidum ssp. dicoccoides) in a typical agricultural field using 16S rRNA and ITS gene sequencing. Our results revealed a high level of conservation in the rhizosphere microbiomes between wild and domesticated wheat, with minimal divergence in community composition and microbial network structure. However, domesticated wheat exhibited a higher prevalence of fungal pathogens and increased functional redundancy, with significant enrichment of genes involved in carbon and nitrogen cycling. The microbial community assemblies in both wheats were predominantly governed by deterministic processes. This suggests that long-term conventional agricultural practices have imposed minor effects on the compositional differences between the microbiomes of wild and domesticated wheat. Nonetheless, the lower abundance of apparent pathogens in the rhizosphere of the wild wheat suggests greater natural biota or innate host plant resistance against pathogenic fungi. This study may provide valuable insights into the host selection, assembly patterns, and functional potential of microbial communities in wild versus domesticated wheat, with implications for manipulating microbial communities in future crop breeding.