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'ND Rodeo' (PVP no. 202300270; Reg. no. CV‐356, PI 703020) is a new slow‐darkening (SD) pinto bean (Phaseolus vulgaris L.) cultivar developed by the Dry Edible Bean Breeding Program at North Dakota State University and released by the North Dakota Agricultural Experiment Station. Pinto bean is the largest market class grown in the United States, representing over 47% of the total US production for dry beans, and more than 70% is produced in North Dakota. SD pinto beans offer a good alternative to commercial cultivars of regular darkening (RD) pinto beans, which are typically subject to the risk of economic losses due to seed coat darkening. However, reaching seed yields comparable to RD pintos has been challenging. Between 2017 and 2022, ND Rodeo was tested across 25 environments in North Dakota, where seed yield was significantly higher than the SD pinto cultivars 'ND Palomino' and 'Vibrant' (18% and 22%, respectively), and comparable with RD pinto cultivars 'La Paz' and 'Monterrey'. ND Rodeo is resistant to Bean common mosaic virus and has intermediate resistance to common bacterial blight, but similar to the commercial checks, it is susceptible to local races/strains of white mold, anthracnose, and rust pathogens. ND Rodeo has an average height of 56 cm which is significantly higher than the average of ND Palomino, Vibrant, and La Paz, and exhibits a desirable upright architecture to facilitate direct harvest. It has a 100‐seed weight of 36.2 g and matures in 102 days. Canning quality was rated as acceptable. Core Ideas: Pinto bean is the most widely grown dry bean market class in the United States.Slow‐darkening pinto beans retain their light cream background seed coat color after harvest.Achieving seed yields comparable to RD pintos has been challenging.Improvements in slow‐darkening pinto bean productivity, upright plant architecture, disease resistance, and seed quality characteristics have been accomplished. [ABSTRACT FROM AUTHOR]

'ND Redbarn' (PVP. no. 202300271; Reg. no. CV‐357, PI 703021) is a new dark red kidney bean (Phaseolus vulgaris L.) cultivar developed by the Dry Edible Bean Breeding Program at North Dakota State University and released in 2023 by the North Dakota Agricultural Experiment Station. Compared to other market classes, kidney beans usually command higher prices. However, kidney beans are less productive than other market classes. Minnesota is the largest dark red kidney bean producer in the United States, accounting for ∼90% of the total production in 2022. ND Redbarn was released based on its good adaptation to this region, higher seed yield, large seed size, and desirable seed shape characteristics. Between 2012 and 2021, ND Redbarn was tested across 16 environments in Minnesota, where seed yield was significantly higher than commercial checks 'Montcalm', 'Red Hawk', and 'Talon' (14%, 27%, and 9%, respectively) and comparable with 'Dynasty'. ND Redbarn is resistant to Bean common mosaic virus and has intermediate resistance to common bacterial blight. ND Redbarn exhibits higher field tolerance to the root rot fungal complex infection compared to Montcalm, Red Hawk, and Talon, and is similar to Dynasty. ND Redbarn has shown higher levels of tolerance to white mold than Montcalm and Red Hawk. Under Minnesota environments, ND Redbarn shows an average plant height of 51 cm, has a 100‐seed weight of 50.4 g, and matures in approximately 99 days. The canning quality for Redbarn is within acceptable commercial ranges. Core Ideas: Dark red kidney bean is the most predominant market class in Minnesota, which accounts for ∼90% of the total US production.Dark red kidney beans are known to be less productive than other bean market classes, but they respond extremely well to good agronomic management.Strict industry and consumer requirements in terms of visual seed quality for kidney beans hinders genetic progress for this market class.Improvements in dark red kidney bean productivity, disease resistance, and size and shape have been accomplished in the new cultivar ND Redbarn. [ABSTRACT FROM AUTHOR]

The Q gene is largely responsible for the widespread cultivation of wheat because it confers the free-threshing character. It also pleiotropically influences many other domestication-related traits such as glume shape and tenacity, rachis fragility, spike length, plant height, and spike emergence time. We isolated the Q gene and verified its identity by analysis of knockout mutants and transformation. The Q gene has a high degree of similarity to members of the AP2 family of transcription factors. The Q allele is more abundantly transcribed than q, and the two alleles differ for a single amino acid. An isoleucine at position 329 in the Q protein leads to an abundance of homodimer formation in yeast cells, whereas a valine in the q protein appears to limit homodimer formation. Ectopic expression analysis allowed us to observe both silencing and overexpression effects of Q. Rachis fragility, glume shape, and glume tenacity mimicked the q phenotype in transgenic plants exhibiting post-transcriptional silencing of the transgene and the endogenous Q gene. Variation in spike compactness and plant height were associated with the level of transgene transcription due to the dosage effects of Q. The q allele is the more primitive, and the mutation that gave rise to Q occurred only once leading to the world's cultivated wheats.

Wild related Triticum species have been and will be a useful reservoir of genetic diversity for solving problems in the development of improved durum (Triticum turgidum L. var. durum) and bread wheat (T. aestivum L.) cultivars. The alien germplasm may be used to reduce vulnerability of cultivars to pests, and improve agronomic fitness and grain quality. However, lack of genetic recombination and hybrid sterility are two obstacles to the use of alien germplasms. Nuclear-cytoplasmic (NC) incompatibility is known to exist between the T. longissimum S. & M. cytoplasm and T. turgidum nucleus. A two-gene system has been found that restores fertility in this situation: the species cytoplasm specific (scs) gene and the vitality (Vi) gene. This gene system can also be used for the production of hybrid wheat. Effects of these genes on euplasmic (true cytoplasm) durum wheat under a field environment had not been previously investigated. In this study, lines with two copies of the sc[s.sup.ti] gene, derived from T. timopheevii Zhnk., were compared to lines without the copy of the gene, the parents, and four durum cultivars for five agronomic characteristics: days to heading, plant height, lodging resistance, grain yield, and kernel test weight. Comparison of genotypes homozygous for the sc[s.sup.ti] gene and those containing no sc[s.sup.ti] gene indicated minor differences among them, confirming that the sc[s.sup.ti] gene does not confer any detrimental effects in the euplasmic situation. Thus, the sc[s.sup.ti] gene could be useful in the production of hybrids in durum wheat., IN THE PAST, alien cytoplasms and chromosomes have been introduced into wheat by cytologically monitoring the chromosomal constitution of backcross progenies in interspecific hybrids (Maan et al., 1999). However, NC [...]

The compatibility-inducing action of the sc[s.sup.ti] (species cytoplasm-specific gene derived from Triticum timopheevii) and Vi (vitality) genes can be observed when a durum (T. turgidum) nucleus is placed in T. longissimum cytoplasm. These two genes restore compatibility between an otherwise incompatible nucleus and cytoplasm. The objective of this study was to localize the sc[s.sup.ti] gene on a linkage map of chromosome 1A, which could eventually be used to clone the gene. The mapping population consisted of 110 [F.sub.2] individuals derived from crossing a Langdon-T. dicoccoides chromosome 1A substitution line with a euplasmic (normal cytoplasm) line homozygous for the sc[s.sup.ti] gene. Through a series of testcrosses the genotypes of the 110 individuals were determined: 22 had two copies, 59 bad one copy, and 29 had no copy of the sc[s.sup.ti] gene. Data from RFLP, AFLP, and microsatellite analysis were used to create a linkage map. The flanking marker loci found for the sc[s.sup.ti] gene were Xbcd12 and Xbcd1449-1A.2 with distances of 2.3 and 0.6 cM, respectively. Nearly 10% of individuals in this population were double recombinant for a genetic interval of

Dry bean (Phaseolus vulgaris L.) is an important worldwide legume crop with low to moderate levels of resistance to common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli. A total of 852 genotypes (cultivars, preliminary and advanced breeding lines) from the North Dakota State University dry bean breeding program were tested for their effectiveness as populations for genome-wide association studies (GWAS) to identify genomic regions associated with resistance to CBB, to exploit the associated markers for marker-assisted breeding (MAB), and to identify candidate genes. The genotypes were evaluated in a growth chamber for disease resistance at both the unifoliate and trifoliate stages. At the unifoliate stage, 35% of genotypes were resistant, while 25% of genotypes were resistant at the trifoliate stage. Libraries generated from each genotype were sequenced using the Illumina platform. After filtering for sequence quality, read depth, and minor allele frequency, 41,998 single-nucleotide polymorphisms (SNPs) and 30,285 SNPs were used in GWAS for the Middle American and Andean gene pools, respectively. One region near the distal end of Pv10 near the SAP6 molecular marker from the Andean gene pool explained 26.7–36.4% of the resistance variation. Three to seven regions from the Middle American gene pool contributed to 25.8–27.7% of the resistance, with the most significant peak also near the SAP6 marker. Six of the eight total regions associated with CBB resistance are likely the physical locations of quantitative trait loci identified from previous genetic studies. The two new locations associated with CBB resistance are located at Pv10:22.91–23.36 and Pv11:52.4. A lipoxgenase-1 ortholog on Pv10 emerged as a candidate gene for CBB resistance. The state of one SNP on Pv07 was associated with susceptibility. Its subsequent use in MAB would reduce the current number of lines in preliminary and advanced field yield trial by up to 14% and eliminate only susceptible genotypes. These results provide a foundational SNP data set, improve our understanding of CBB resistance in dry bean, and impact resource allocation within breeding programs as breeding populations may be used for dual purposes: cultivar development as well as genetic studies. [ABSTRACT FROM AUTHOR]

Plant disease resistance is often conferred by genes with nucleotide binding site (NBS) and leucine-rich repeat (LRR) or serine/threonine protein kinase (S/TPK) domains. Much less is known about mechanisms of susceptibility, particularly to necrotrophic fungal pathogens. The pathogens that cause the diseases tan spot and Stagonospora nodorum blotch on wheat produce effectors (host-selective toxins) that induce susceptibility in wheat lines harboring corresponding toxin sensitivity genes. The effector ToxA is produced by both pathogens, and sensitivity to ToxA is governed by the Tsnl gene on wheat chromosome arm 5BL. Here, we report the cloning of Tsnl, which was found to have disease resistance gene-like features, including SITPK and NBS-LRR domains. Mutagenesis revealed that all three domains are required for ToxA sensitivity, and hence disease susceptibility. Tsnl is unique to ToxA-sensitive genotypes, and insensitive genotypes are null. Sequencing and phylogenetic analysis indicated that Tsnl arose in the B-genome diploid progenitor of polyploid wheat through a gene-fusion event that gave rise to its unique structure. Although Tsnl is necessary to mediate ToxA recognition, yeast two-hybrid experiments suggested that the Tsnl protein does not interact directly with ToxA. Tsn1 transcription is tightly regulated by the circadian clock and light, providing further evidence that Tsnl-ToxA interactions are associated with photosynthesis pathways. This work suggests that these necrotrophic pathogens may thrive by subverting the resistance mechanisms acquired by plants to combat other pathogens. [ABSTRACT FROM AUTHOR]

The wheat- Stagonospora nodorum pathosystem involves a number of pathogen-produced host-selective toxins that interact with host genes in an inverse gene-for-gene manner to cause disease. The wheat intervarietal recombinant inbred population derived from BR34 and Grandin (BG population) segregates for the toxin sensitivity genes Tsn1, Snn2, and Snn3, which confer sensitivity to the toxins ToxA, SnTox2, and SnTox3, respectively. Here, we report the addition of 141 molecular markers to the BG population linkage maps, the identification and/or development of markers tightly linked to Tsn1 and Snn2, and the validation of the markers using a set of diverse wheat accessions. The BG population maps now contain 787 markers, and new simple sequence repeat (SSR) markers closely linked to Snn2 on chromosome arm 2DS were identified. In an effort to target more markers to the Snn2 locus, STS markers were developed from 2DS bin-mapped ESTs resulting in the development and mapping of 36 markers mostly to the short arms of group 2 chromosomes. Together, SSR and EST-STS markers delineated Snn2 to a 4.0 cM interval. SSRs developed in related work for Tsn1 were mapped in the BG population and delineated the gene to a 1.0 cM interval. Evaluation of the markers for Tsn1 and Snn2 in a diverse set of wheat genotypes validated their utility for marker-assisted selection, which is particularly efficient for removing toxin sensitivity alleles from elite germplasm and varieties. [ABSTRACT FROM AUTHOR]

Pea seed-borne mosaic virus (PSbMV), a nonpersistently aphid-transmitted potyvirus, has been reported in field pea ( Pisum sativum L.)-growing regions worldwide. In 2014, PSbMV was first identified in field peas in North Dakota, U.S.A. Susceptibility and yield losses attributed to PSbMV infection are influenced by viral pathotype and host genotype. Isolate ND14-1, recovered from North Dakota infected seed and identified as pathotype 4 (P4), was mechanically inoculated onto 20 field pea cultivars under greenhouse conditions. PSbMV susceptibility, number of seeds and pods per plant, yield, symptom expression, and PSbMV seed transmission rates were assessed by cultivar. A risk assessment was developed based on cultivar susceptibility, yield reduction, and PSbMV seed transmission. Risk factors were weighted based on perceived importance to commercial field pea producers. Three cultivars were classified as low risk, seven cultivars were classified as intermediate risk, and 10 cultivars were classified as high risk. Two of the low-risk cultivars, Aragorn and Cruiser, were confirmed to be resistant to this isolate of PSbMV. Cultivar Arcadia was susceptible to PSbMV infection with mild expression of symptoms, but was classified as low risk based on a low seed transmission rate and diminished yield losses. This risk assessment could prove a useful tool for growers in field pea cultivar selection where PSbMV is prevalent.