Page 269 - Plant Canada 2024 Proceeding

PLANT CANADA 2024

variation was used as an input for a genome-wide association study, from which we identified nine
genetic loci that might contribute to cowpea drought resilience during early vegetative development. The
homologs of the candidate genes were identified in Arabidopsis (Arabidopsis thaliana) and subsequently
evaluated for their involvement in drought stress by using available T-DNA insertion mutant lines. These
results demonstrate the varied applicability of this low-cost phenotyping system. In the future, we foresee
these setups facilitating the identification of genetic components of growth, plant architecture, and stress
tolerance across a wide variety of plant species.

[P132] REGULATION OF A SINGLE INOSITOL 1-PHOSPHATE SYNTHASE HOMOLOGY BY
HSFA6B CONTRIBUTES TO FIBER YIELD MAINTENANCE UNDER DROUGHT CONDITIONS IN
UPLAND COTTON. Li’ang Yu , Anna C. Nelson Dittrich , Xiaodan Zhang , Venkatesh P.
1
1
1
2
4
2,6
1,5
Thirumalaikumar , Giovanni Melandri , Aleksandra Skirycz , Kelly R. Thorp , Lori Hinze , Duke Pauli ,
1
3
and Andrew D.L. Nelson . Boyce Thompson Institute, Cornell University, Ithaca, NY 14850, USA;
1 1
2 School of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA; United States Department of
3
Agriculture-Agricultural Research Service, Arid Land Agricultural Research Center, Maricopa, AZ 85138,
USA; United States Department of Agriculture-Agricultural Research Service, Southern Plains
4
Agricultural Research Center, College Station, TX 77845, USA; Current address: Purdue Proteomics
5
6
Facility, Bindley biosciences, Purdue University, West Lafayette, IN, 47907, USA; and Agroecosystem
Research in the Desert (ARID), University of Arizona, Tucson, AZ 85721
Correspondence to: an425@cornell.edu

Drought stress substantially impacts crop physiology resulting in alteration of growth and productivity.
Understanding the genetic and molecular crosstalk between stress responses and agronomically
important traits such as fiber yield is particularly complicated in the allopolyploid species, upland cotton
(Gossypium hirsutum), due to reduced sequence variability between A and D subgenomes. To better
understand how drought stress impacts yield, the transcriptomes of 22 genetically and phenotypically
diverse upland cotton accessions grown under well-watered and water-limited conditions in the Arizona
low desert were sequenced. Gene co-expression analyses were performed, uncovering a group of stress
response genes, in particular transcription factors GhDREB2A-A and GhHSFA6B-D, associated with
improved yield under water-limited conditions in an ABA-independent manner. DNA affinity purification
sequencing (DAP-seq), as well as public cistrome data from Arabidopsis, were used to identify targets of
these two TFs. Among these targets were two lint-yield associated genes previously identified through
genome-wide association studies (GWAS) -based approaches, GhABP-D and GhIPS1-A. Biochemical
and phylogenetic approaches were used to determine that GhIPS1-A is positively regulated by
GhHSFA6B-D, and that this regulatory mechanism is specific to Gossypium spp. containing the A (old-
world) genome. Finally, a SNP was identified within the GhHSFA6B-D binding site in GhIPS1-A that is
positively associated with yield under water limiting conditions. These data lay out a regulatory connection
between abiotic stress and fiber yield in cotton that appears conserved in other systems such as
Arabidopsis. This regulatory mechanism highlights how sub-genome dynamics contribute to phenotypic
stress-response plasticity in cotton.

[P133] MOLECULAR SCREENING OF BACTERIA IN CANADIAN GRAINS. Tehreem Ashfaq , Niradha
1
Withana Gamage , Janice Bamforth , and Sean Walkowiak . Grain Research Laboratory, Canadian
1
1 1
1
Grain Commission, 196 Innovation Drive, Winnipeg, MB, Canada, R3T 2N2
Correspondence to: sean.walkowiak@grainscanada.gc.ca

Bacteria are prevalent and play a vital role in maintaining global biodiversity. They can either be beneficial
to our health as gut microbiome which exists symbiotically within the human digestive system, can be
harmful to humans and animals by causing disease, or can coexist as neutral members of the
microbiome. Studying the bacteria within grains is important for understanding the potential risks and
benefits of them, ensuring the grain quality and safety. We monitor bacteria on grains according to Health
Canada's MFLP-52 protocol, with some modifications, and have established a procedure that allows us to
test hundreds of raw grain samples including wheat, barley, soybean, corn, canola and etc. for the
presences of different bacteria each year. Our protocol involves culturing and enriching bacteria from the
grains. This process begins with measuring 25g of each sample, placed in a sterilized pulsified bags. The
grains are first soaked in Buffered Peptone Water (BPW) followed by 100% Tryptic Soy Broth (TSB).
Then the samples are incubated at 42°C to promote the growth of bacteria. After 20-24 hours of

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