Plant age influences microbiome communities more than plant compartment in greenhouse grown creeping bentgrass

Authors: DOHERTY, JOSEPH - University Of Maryland; Crouch, Jo Anne; ROBERTS, JOSEPH - University Of Maryland

Submitted to: Phytobiomes Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2021
Publication Date: 6/22/2021
Citation: Doherty, J., Crouch, J.A., Roberts, J. 2021. Plant age influences microbiome communities more than plant compartment in greenhouse grown creeping bentgrass. Phytobiomes Journal. 5(4):373-381. https://doi.org/10.1094/PBIOMES-03-21-0021-R.
DOI: https://doi.org/10.1094/PBIOMES-03-21-0021-R

Interpretive Summary: The microscopic organisms that live in association with plants have a tremendous impact on the health of their host, in both good and bad ways. As a plant grows from seed, a unique set of microorganisms, collectively known as the microbiome, simultaneously grows inside the plant. For turfgrasses such as creeping bentgrass, the make-up of the microbiome from seed germination through plant maturity is unknown. By generating a series of microbiome DNA barcodes over time from different plant parts, we determined that as a creeping bentgrass seed grows into a young plant, the fungal microbiome is consistent over time and in different plant parts. However, the bacterial microbiome changes based on plant part and through time. These findings are important because they show the connection between the plant age, plant part and the microbiome, which will aid in future research efforts in creeping bentgrass health management.

Technical Abstract: Creeping bentgrass (Agrostis stolonifera L.) is widely used in golf course settings for its desirable characteristics as a playing surface, however it is highly susceptible to many diseases that can disrupt surface integrity and cause significant losses despite preventative management actions. Understanding the influence of early plant growth stages and basic management practices have on the creeping bentgrass microbiome are crucial first steps to develop tools to manipulate and harness the microbiome for improved plant health. This study investigated bacterial and fungal communities of newly seeded creeping bentgrass foliage and rhizosphere through six months post-emergence under controlled environment conditions to elucidate the community dynamics of the microbiome in response to plant age. We hypothesized that there are distinct community structures between plant compartments and that each compartment will exhibit different variations over time. Our results showed that the predominant bacterial phyla and fungal classes remain consistent across time and plant compartment. However, taxonomic classification below the class level reveals bacterial taxa differed across plant compartment while fungal taxa remained consistent between compartments. Host influence over the microbiome manifests itself quickly, with the largest shift in both microbial communities occurring between emergence and two months post-emergence. For example, Burkholderia spp. and Penicillium spp. 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.