Page 129 - Plant Canada 2024 Proceeding

PLANT CANADA 2024

This approach, called ‘Participatory Plant Breeding’ (PPB) has gained momentum in the last 30 years
under low-input, challenging environments in developing countries. However, PPB programs are now
expanding across the Global North to meet the needs of the underserved organic industry. Canada’s first
PPB program in wheat was established in 2011 in partnership with plant breeders with Agriculture and
Agri-Food Canada, and the University of Manitoba’s Natural Systems Agriculture Research Group. The
program worked with over 75 farmers across Canada, generating over 50 wheat genotypes on a diversity
of farms. We will report experimental data from trials testing spring wheat ‘farmer genotypes’ vs. checks
under organic management in 12 environments. Average environment yields ranged from 714 to 4382 kg
-1
ha . Multiple farmer genotypes performed just as well and, in many cases, better than check cultivars.
Using three yield stability models demonstrated that 3 farmer genotypes and one check were top
performers and most adapted to organic conditions. Another farmer genotype demonstrated high yield,
but also superior stability according to the Finlay-Wilkinson test and GGE Biplot analysis. AAC Brandon,
one of the most popular commercial cultivars in Manitoba, was found to have low yield and poor
adaptation to organic environments. In addition to performance data, we will also share successes and
logistical challenges we experienced running the program, as well as future opportunities for Canadian
agriculture.

[O55] EXAMINING THE RELATIONSHIP BETWEEN BACTERIAL BROWN SPOT AND COMMON
1,2
2
1
2
BACTERIAL BLIGHT IN COMMON BEAN. Caio Correa , Emily Morneau , Owen Wally , Chris Gillard ,
and Jamie Larsen . Department of Plant Agriculture, University of Guelph-Ridgetown Campus,
2 1
2
Ridgetown, ON, Canada, N0P 2C0; Harrow Research and Development Centre, Agriculture and Agri-
Food Canada, Harrow, ON, Canada, N0R 1G0
Correspondence: jamie.larsen@agr.gc.ca

Bacterial Blights caused by Xanthomonas axonopodis var. phaseoli (Common Bacterial Blight; CBB) and
Pseudomonas syringae pv. syringae (Bacterial Brown Spot; BBS) are important dry bean (Phaseolus
vulgaris L.) diseases. These pests are challenging to deal with as they are known to be endemic to most
dry bean growing regions and are seedborne, limiting the ability to control disease transmission in seed
produced in humid regions like Ontario. Producers are impacted by increased cost of production due to
disease-free pedigreed seed production being completed in semi-arid regions, a 20%-45% yield reduction
due to impacts on plant health in field outbreaks and a reduction in seed coat quality leading to ‘pick’ loss
when sorted by seed handlers after harvest. Previously, it was thought that CBB was the primary cause of
bacterial blights in Ontario, however BBS had not been explored to determine if this disease is present
and what impact it has on dry bean varieties grown in Ontario.

Dry bean disease surveys of leaves and seed harvest samples indicated that both CBB and BBS
pathogens are found across Ontario, with BBS being most prevalent. Through the use of artificially
inoculated CBB and BBS nurseries over 400 cultivars were tested from multiple market classes for
reaction to these pathogens. Analysis of data found a significant positive correlation for disease reaction
between these two diseases in white bean and small seeded coloured beans, but not for large seeded
coloured beans. A subset of 70 cultivars were assayed using molecular markers linked to CBB
resistance. A significant molecular marker association was found for both diseases, indicating that
resistance to one pathogen was generally associated with resistance to the other, meaning that CBB
resistance genes are effective for both diseases. To explore bacterial blight resistance in large seeded
coloured beans, three kidney bean populations of 125 recombinant inbred lines each were developed
using USDK CBB-15 as a CBB resistant common parent. The three populations were screened for BBS
and CBB severity in field-based nurseries and a restricted two stage multi-locus genome-wide association
study (RTM-GWAS) was performed using genotype by sequencing molecular marker data to detect single
nucleotide polymorphisms potentially linked to resistance genes. In total, 26 and 23 major QTL for BBS
and CBB, respectively were identified. These results provide key information on genomic regions that
could be selected to improve bacterial blight resistance in kidney beans.

128