Plant Age Influences Microbiome Communities More Than Plant Compartment in Greenhouse Grown Creeping Bentgrass

Creeping bentgrass (Agrostis stolonifera L.) is widely used in golf course settings for its desirable playing surface characteristics, however it is highly susceptible to diseases that can disrupt surface integrity and cause significant losses despite preventative management. Understanding the influence of early plant growth and basic management practices on microbiome communities are crucial first steps to developing future efforts to harness the microbiome for plant health. This study investigated bacterial and fungal communities of creeping bentgrass foliage and rhizosphere through six months post-emergence under a controlled environment to elucidate microbiome community dynamics in response to plant age. We hypothesized that plant compartments will host distinct community structures and exhibit different responses to plant age. Our results showed that predominant bacterial phyla and fungal classes remain consistent across time and plant compartment. However, genus level classification revealed bacterial taxa differed across plant compartment while fungal taxa remained consistent. Host influence over the microbiome manifests quickly, with the largest shift in both microbial communities occurring between emergence and two months post-emergence. For example, Burkholderia and Penicillium were present at high relative abundance at emergence, but by two months post-emergence both taxa decreased significantly. Bacterial communities continued to experience significant fluctuation in rare taxa from two months post-emergence onward, while fungal community structure was driven by the fluctuation of the most common taxa. These results highlight the connection between plant age and microbial community structure in creeping bentgrass in addition to underscoring future research efforts in creeping bentgrass microbiome manipulation for plant health.