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Bacterial brown spot (BBS) caused by Pseudomonas syringae pv. syringae (Pss), common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) and Xanthomonas fuscans subsp. fuscans (Xff), and halo bacterial blight (HBB), caused by Pseudomonas syringae pv. phaseolicola (Psph), are major bacterial diseases that severely affect common bean yields and global food security. Andean-origin dry beans, representing large-seeded market classes, are particularly susceptible. Using 140,325 SNPs, a multi-locus GWAS was conducted on subsets of the Andean diversity panel (ADP) phenotyped for BBS in South Africa, CBB in Puerto Rico, South Africa, and Zambia, and HBB in South Africa, through natural infection, artificial inoculation, or both. Twenty-four QTL associated with resistance were identified: nine for BBS, eight for CBB, and seven for HBB. Four QTL intervals on Pv01, Pv03, Pv05, and Pv08 overlapped with BBS and HBB resistance. A genomic interval on Pv01, near the fin gene, which determines growth habit, was linked to resistance to all three pathogens. Different QTLs were detected for BBS and CBB resistance when phenotyped under natural infection versus artificial inoculation. These results underscore the importance of combining phenotyping methods in multi-GWAS to capture the full genetic spectrum. Previously recognized CBB resistance QTL SAP6 and SU91 and HBB resistance QTL HB4.2, and HB5.1, were observed. Other common (MAF >0.25) and rare (MAF <0.05) resistance QTL were also detected. Overall, these findings enhance the understanding and utilization of bacterial resistance present in ADP for the development of common beans with improved resistance. [ABSTRACT FROM AUTHOR]

'Kikatiti' pinto bean (Phaseolus vulgaris L.) (Reg. no. CV‐361, PI 705149) was developed by the dry bean breeding program at the University of Nebraska, Agricultural Research Division, and submitted for release in 2021 by the Sokoine University of Agriculture in Morogoro as an upright indeterminate pinto bean with high yield potential and multiple disease resistance across bean production environments in Tanzania. Kikatiti was officially released in 2024 by the National Seed Committee. Kikatiti is an F7:8 derived line developed using the pedigree breeding method in Nebraska. The exceptional performance of Kikatiti in Tanzania was first identified by evaluation of the Durango Diversity Panel (DDP), which consisted of 200 accessions in on‐station trials conducted in Arusha and Mbeya. Kikatiti was identified as accession DDP‐094 (advanced breeding line NE2‐09‐3). Kikatiti yielded 1584 kg ha−1 across 5 years of trials in Tanzania and matured in 89 days. Kikatiti is resistant to bean rust conferred by the Ur‐3 and Ur‐11 genes, resistant to all strains of Bean common mosaic virus and Bean common mosaic necrosis virus conferred by the I and bc‐3 genes, moderately resistant to common bacterial blight conferred by the SAP6 quantitative trait locus, avoids white mold disease due to its upright architecture, and is moderately susceptible to angular leaf spot disease. Kikatiti has large seed size (35.9 g 100 seeds−1), and in on‐farm trials, farmers ranked Kikatiti above local pinto cultivars for its performance and market potential. Kikatiti has the potential to expand pinto bean production across East Africa. Core Ideas: Kikatiti pinto bean has superior productivity in Tanzania.Kikatiti pinto possesses an effective combination of resistance genes to combat bean rust disease in East Africa.Kikatiti pinto possesses an effective combination of resistance genes to combat Bean common mosaic necrosis virus.Farmers ranked Kikatiti above local pinto cultivars for performance and market potential in on‐farm trials. [ABSTRACT FROM AUTHOR]

The pinto bean (Phaseolus vulgaris L.), 'USDA Rattler' (Reg. no. CV‐350, PI 693789), was released by the USDA‐ARS in 2021 as a high‐yielding, upright, full‐season cultivar with abiotic stress tolerance. It was bred for broad adaptation to the different bean production regions across the United States by selection for high yield performance under nonstress and multiple stress trials in Washington state. The multiple stress trials included a "purgatory" plot with low fertility, intermittent drought, and soil compaction, and a separate trial which simulated terminal drought. Conversely, the nonstress trials were well watered and fertilized to optimize yield potential. Yield stability is evidenced by the mean seed yield for the breeding line PT11‐13, from which USDA Rattler was selected, numerically exceeding the trial means for 33 of 38 location‐years. Broad adaptation for USDA Rattler is further evidenced by an average seed yield of 4547 kg ha−1 across 10 location‐years in the Cooperative Dry Bean Nursery. Genetic markers as well as pathogen testing indicate USDA Rattler has I and bc‐3 gene combination for durable resistance to all known strains of Bean common mosaic virus and Bean common mosaic necrosis virus. Greenhouse testing with four races of the rust pathogen indicated USDA Rattler is fixed for the Ur‐3 resistance gene but is heterogenous for presence of the Ur‐11 resistance gene. The seed size, appearance, and canning quality characteristics of USDA Rattler meets the industry standards for packaging and processing. Core Ideas: USDA Rattler was bred for high yield potential under both favorable and stressful environments.USDA Rattler performed well in our "purgatory plot" used to select for drought and low soil fertility tolerance.USDA Rattler is resistant to all known strains of Bean common mosaic virus and Bean common mosaic necrosis virus.USDA Rattler is widely adapted to production regions across the United States. [ABSTRACT FROM AUTHOR]

Bean common mosaic virus (BCMV) and bean common mosaic necrosis virus (BCMNV) have a damaging impact on global common bean (Phaseolus vulgaris L.) cultivation, causing potential yield losses of over 80%. The primary strategy for controlling these viruses is through host plant resistance. This research aimed to identify and validate structural variations for the bc-u d gene as revealed by long-read sequencing, develop an efficient DNA marker to assist selection of bc-u d in snap and dry beans, and examine the interactions between the bc-u d allele and other BCMV resistance genes. A gene (Phvul.005G125100) model on chromosome Pv05, encoding a vacuolar protein-sorting 4 (Vps4) AAA+ ATPase endosomal sorting complexes required for transport (ESCRT) protein, was identified as the best candidate gene for bc-u d . An 84-bp repetitive insertion variant within the gene, exhibited 100% co-segregation with the bc-u d resistance allele across 264 common bean accessions. The 84-bp repetitive insertion was labeled with an indel marker IND&#95;05&#95;36225873 which was useful for tracking the bc-u d allele across diverse germplasm. A different single nucleotide polymorphism variant within the same candidate gene was associated with the bc-4 gene. Segregation in F 2 populations confirmed bc-u d and bc-4 were alleles, so bc-4 was renamed bc-u r to fit gene nomenclature guidelines. The interactions of bc-u d and bc-u r with other resistance genes, such as bc-1 (receptor-like kinase on Pv03) and bc-2 (Vps4 AAA+ ATPase ESCRT protein on Pv11), validated gene combinations in the differential "host groups" effective against specific BCMV/BCMNV "pathogroups." These findings increase our understanding of the Bc-u locus, and enhance our ability to develop more resilient bean varieties through marker-assisted selection, reducing the impact of BCMV and BCMNV., (© 2023 The Authors. The Plant Genome published by Wiley Periodicals LLC on behalf of Crop Science Society of America. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)