Page 46 - TriSociety Virtual Event

Abstracts

efects of phytopathogens through a variety of microbiomes associated with plants relies impact of T. gamsii application on bacterial
mechanisms Some PGPB encode the enZyme on high­throughput sequencing and analysis and fungal communities associated with
ACC deaminase which cleaves ACC the imme­ using either an amplicon or metagenomic diferent wheat tissues T. gamsii was applied
diate precursor or ethylene in all higher plants approach Diagnostic metagenomic approach­ on soil crop residues at the beginning of stem
and thereby lowers ethylene levels which es are emerging by coupling metagenomics elongation of wheat plants and wheat spikes
would other wise be increased to growth to available whole genome sequences type at anthesis Wheat spikes kernels and residue
inhibitory levels following various abiotic or strains and other reference strains These from the previous year's wheat crop were col­
biotic stresses These stresses include fungal methods changed the type of labor required lected at diferent time points for microbiome
and bacterial phytopathogens high levels of the volume of resulting data collected and profiling and quantification of F. graminearum
salt flooding drought the presence of heavy the training needed by researchers to plan ex­ and T. gamsii densities Densities of T. gamsii
metals or organic contaminants extremes of ecute and analyZe these experiments Further­ and F. graminearum were considerably high
temperature and the presence of nematodes more culture­independent methods (­omics) in residue while their detection rates in spikes
Plants treated with PGPB (with ACC deami­ are moving us beyond cataloging organisms and kernels were lower The application of
nase) typically have greater root and shoot associated with plants to understanding the T. gamsii did not change the F. graminearum
growth and are significantly healthier than un­ functional relationships among members of density Despite the limited impacts of T. gam­
treated plants Some of the other mechanisms the phytobiome in situ Spatial and temporal sii application there were clear diferences in
possessed by PGPB (such as IAA synthesis N multi­omic studies are required to tease apart microbial community structure over time In
fixation and trehalose biosynthesis) can act sy­ complex phytobiome interactions Innova­ crop residue the F. graminearum density had
nergistically with ACC deaminase in promoting tive approaches to capture store and use decreased over time while in wheat spikes it
plant growth Also the functioning of RhiZobia microbiome assemblages are allowing us to had increased over time The crop residue had
that form specific relationships (nodules) with assess the impact of these assemblages and the highest microbial diversity and compara­
legume roots and fix nitrogen for the host circle back to principles attributed to Koch tively diferent microbial community structure
plant is significantly promoted by the presen­ In addition to examples of current work and In wheat spikes and kernels the predominant
ce of ACC deaminase In the past 10­20 years new frontiers with this presentation I hope to bacterial genera were Pseudomonas Pantoea
scientists worldwide have de veloped a much provide a few first steps for those who have and Enterobacter and the predominant fungal
better understanding of the mechanisms used not yet used microbiome sciences tools to genera were Alternaria and Fusarium These
by PGPB so that many strains of these bacteria help test their hypotheses results indicate a minor impact of T. gamsii
have begun to be commercialiZed throughout application on the microbiome associated
the world including Canada Session 13. Student oral competi­ with wheat tissues
tion: Plant and Soil Health and the
Session 12. Invited keynote Microbiome 64. Creeping bentgrass microbiome: tra­
speaker ditional culturing and sequencing results
compared to metagenomic techniques.
63. Does application of Trichoderma
62. The second century of phytobiome gamsii T6085 for control of Fusarium head E MCNAB D BENEDETTO AND T HSIANG
research blight alter the microbiome of wheat? School of Environmental Sciences, University of
C T BULL Department of Plant Pathology and A S ALUKUMBURA W G D FERNANDO S Guelph, 50 Stone Road East, Guelph, ON N1G
Environmental Microbiology and The Penn SARROCCO A BIGI G VANNACCI AND M G 2W1, Canada
State Microbiome Center, The Pennsylvania BAKKER Department of Plant Science, Uni­
State University, 111 Buckhout Laboratory, versity of Manitoba, 66 Dafoe Road, Winnipeg, Recent metagenomic studies have been
University Park, PA, 16802 USA. MB R3T 2N2, Canada; (M.B.) Department of probing the fungal microbiome of intensively
Microbiology, 45 Chancellor’s Circle, Winni­ managed turfgrasses to better understand
Researchers in plant sciences environmental peg, MB R3T 2N2, Canada; and (S.S., A.B., G.V.) organisms present which might be potential­
microbiology and plant pathology have been Department of Agriculture, Food and Environ­ ly beneficial or harmful but the taxonomic
studying phytobiomes for over a centur y using ment, University of Pisa, Lungarno Pacinotti 43, resolution obtained in these studies is ofen
principles based on Koch's 1890 publication to 6126 Pisa, Italy limited to the family or genus level This may
attribute plant health resiliency and produc­ be related to the common practice of targeting
tivity phenotypes to interactions with micro­ Fusarium head blight (FHB) caused mainly by short sequences of rDNA (18S ITS1 or ITS2 re­
organisms In the past 50 years the methods Fusarium graminearum is a ma or constraint gions) for the estimation of fungal abundance
used to catalogue the presence and absence to wheat production worldwide Trichoderma and phylogenetic relationships In this study
or diversity of microorganisms associated gamsii has shown promise as a potential we collected samples from Guelph Ontario
with these phenotypes have changed but the biocontrol agent to manage FHB in wheat of intensively managed creeping bentgrass
principle of consistent association remains However the impact of T. gamsii application (Agrostis stolonifera L ) across two growing
the same The move from culture­dependent on the wheat microbiome is not known seasons and obtained 2204 foliar epiphytic
to culture­independent characteriZation of The ob ective of this study is to evaluate the fungal isolates Subsequent sequencing of the
entire ITS region of 248 representative isolates

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