Page 146 - Plant Canada 2024 Proceeding

PLANT CANADA 2024

changes in gene expression by performing RNAseq in partially resistant and susceptible pea lines
inoculated with F. avenaceum isolate 1306.08. Four pea genotypes including three partially resistant (PR)
genotypes, K-2, 5001, and Carman and one susceptible (S) genotype, CDC Meadow were grown in
standard greenhouse conditions. After 14 days of growth, the plants were inoculated with macroconidia of
F. avenaceum, and the controls were treated with sterile water. The root tissue was sampled at 2 hours
post-inoculation, followed by 3, 6, and 9 days post-inoculation and samples were subjected to RNA
extraction and RNAseq analysis. The roots were rated for disease severity at 21 days post-inoculation. Of
the five genotypes, K-2 had significantly lower disease severity compared to CDC Meadow. RNAseq of
samples from four genotypes revealed a total of more than 18,000 differentially expressed genes among
inoculated and un-inoculated roots of all the genotypes at all time points. Those differentially expressed
genes were related to pathways such as plant-pathogen interactions, biosynthesis of secondary
metabolites and photosynthesis. Detailed results for each genotype and time points will be discussed.

*[O89] METABARCODING REVEALS BACTERIAL ENDOPHYTES FROM BARLEY GRAINS ARE
SIGNIFICANTLY ASSOCIATED WITH FUSARIUM HEAD BLIGHT, BARLEY GENOTYPE, AND TIME
1
5
OF SAMPLING. Vinuri Weerasinghe 1,2,3 , Matthew Bakker , James Tucker , Dilantha Fernando , Ana
4
. Department of Plant Science, University of Manitoba, 66 Dafoe
Badea , and Champa Wijekoon 1,2,3 1
1,5
Road, Winnipeg, MB, Canada, R3T 2N2; Morden Research and Development Centre, Agriculture and
2
Agri-Food Canada, Route 100, Unit 100-101, Morden, MB, Canada, R6M 1Y5; Canadian Centre for Agri-
3
Food Research in Health and Medicine, 351 Taché Avenue, Winnipeg, MB, Canada, R2H 2A6;
4 Department of Microbiology, University of Manitoba, 213 Buller Building, Winnipeg, Manitoba, R3T 2N2;
and Brandon Research and Development Centre, Agriculture and Agri-Food Canada, 2701 Grand Valley
5
Road, P.O. Box 1000A, Brandon, MB, Canada, R7A 5Y3
Correspondence to: weerasi1@myumanitoba.ca

Barley (Hordeum vulgare L.) is the fourth most cultivated cereal crop in the world, and Canada is among
the top ten barley producers. Fusarium head blight (FHB) is a destructive fungal disease in barley,
affecting several industries including livestock feed and malting, leading to significant economic losses.
The main pathogen, Fusarium graminearum, infects barley spikes and degrades grain quality. Changes in
the plant microbiome, in particular the endophytes, may indicate changes in plant physiology, anatomy,
and resistance to abiotic and biotic stress conditions. Interactions of endophytes with hosts and other
microbes play a role in maintaining a plant’s health. In fact, certain endophytes may be involved in
defense against phytopathogens and plant growth improvement. Despite this, studies on endophytes of
barley genotypes grown in Canada are limited. In this study, we investigated the endophytic microbiome
of barley genotypes grown in Canada, with a focus on bacteria. Surface sterilized barley grains collected
from 2021 and 2022 at the mid-dough stage and harvest stage were targeted for bacterial 16S rRNA
amplicon sequencing using Illumina platform. Following a quality check, the sequence reads were
trimmed, merged, dereplicated, and taxonomically ranked with reference to Silva database (v138.1). A
taxonomic filtering was performed to remove amplicon sequence variants (ASVs) from non-bacterial,
chloroplast and mitochondrial origin. Thereafter, a statistical analysis was performed on the
metabarcoding data using phyloseq (v1.42.0) and MaAsLin 2 (v1.12.0) packages in R software (v4.2.3).
The analysis indicated that Proteobacteria, Actinobacteriota and Firmicutes were predominant in the
barley grain endosphere. Significant associations of bacterial ASVs with FHB, barley genotype, plant
developmental stage and the growing season were demonstrated which may be used as indicators of
FHB-resistance, for instance. In addition, the vertical transmission of bacterial endophytes via barley
grains was investigated which may be applied for future breeding programs. Altogether, the findings of
this study will benefit the breeders, growers, industries, and consumers of barley and barley-related
products.

*[O90] COMMERCIAL FORMULATIONS CONTAINING BACILLUS SPECIES REDUCE THE
DEVELOPMENT AND SURVIVAL OF FUSARIUM OXYSPORUM IN SOIL-LESS GROWTH MEDIA.
1
Denna N. Dalrymple and Zamir K. Punja . Department of Biological Sciences, Simon Fraser University,
1 1
8888 University Drive, Burnaby, BC V5A 1S6, Canada
Correspondence to: denna_dalrymple@sfu.ca

The genus Bacillus is a widely used bacterial group in research on the biological control of pests and
pathogens. They are free-living beneficial microbes, many of which are plant growth-promoting

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