This study investigates the diversity and heritability of the maize rhizosphere microbiome under field conditions. Researchers analyzed the bacterial diversity of 27 modern maize inbreds grown in five field environments across three U.S. states. Using pyrosequencing of 16S rRNA genes, they observed significant variation in bacterial richness, diversity, and relative abundances between bulk soil and the maize rhizosphere, as well as between fields. The results showed that a small but significant portion of total bacterial diversity was heritable across fields, while there was substantially more heritable variation between replicates of the inbreds within each field. The study highlights the importance of environmental factors in shaping microbial communities and suggests that plant-microbe interactions could be incorporated into plant breeding through genome-wide association studies. The rhizosphere is a critical interface where plants interact with soil microbes, and microbial diversity is influenced by both environmental and genetic factors. The study found that the rhizosphere microbiota of maize inbreds exhibited significant variation in diversity and composition, with some taxa being consistently enriched in the rhizosphere. The results also showed that soil physicochemical properties, such as pH and nutrient availability, played a significant role in shaping microbial communities. However, the study found that host genetics had a smaller but significant effect on microbial diversity, with some variation explained by interactions between maize inbred genotypes and field environments. The study also found that the rhizosphere microbiota differed from bulk soil microbiota, with the rhizosphere showing greater β-diversity. The results suggest that the rhizosphere microbiota is influenced by both environmental and genetic factors, and that the interaction between plant genotype and environment is important in shaping microbial communities. The study highlights the need for further research to identify the specific alleles responsible for microbial variation and to understand the functional roles of microbial diversity in plant growth and development. The findings have implications for plant breeding and biotechnology, as they suggest that plant-microbe interactions could be incorporated into breeding programs to improve plant performance.This study investigates the diversity and heritability of the maize rhizosphere microbiome under field conditions. Researchers analyzed the bacterial diversity of 27 modern maize inbreds grown in five field environments across three U.S. states. Using pyrosequencing of 16S rRNA genes, they observed significant variation in bacterial richness, diversity, and relative abundances between bulk soil and the maize rhizosphere, as well as between fields. The results showed that a small but significant portion of total bacterial diversity was heritable across fields, while there was substantially more heritable variation between replicates of the inbreds within each field. The study highlights the importance of environmental factors in shaping microbial communities and suggests that plant-microbe interactions could be incorporated into plant breeding through genome-wide association studies. The rhizosphere is a critical interface where plants interact with soil microbes, and microbial diversity is influenced by both environmental and genetic factors. The study found that the rhizosphere microbiota of maize inbreds exhibited significant variation in diversity and composition, with some taxa being consistently enriched in the rhizosphere. The results also showed that soil physicochemical properties, such as pH and nutrient availability, played a significant role in shaping microbial communities. However, the study found that host genetics had a smaller but significant effect on microbial diversity, with some variation explained by interactions between maize inbred genotypes and field environments. The study also found that the rhizosphere microbiota differed from bulk soil microbiota, with the rhizosphere showing greater β-diversity. The results suggest that the rhizosphere microbiota is influenced by both environmental and genetic factors, and that the interaction between plant genotype and environment is important in shaping microbial communities. The study highlights the need for further research to identify the specific alleles responsible for microbial variation and to understand the functional roles of microbial diversity in plant growth and development. The findings have implications for plant breeding and biotechnology, as they suggest that plant-microbe interactions could be incorporated into breeding programs to improve plant performance.