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The value of glyphosate to growers practicing minimum or no‐till farming has been primarily a function of three factors: broad‐spectrum weed control, little to no carryover effect, and cost effectiveness. A 2‐year field study was conducted in 2021 and 2022 at the University of Idaho Research and Extension Centers at Kimberly and Aberdeen, ID, to evaluate the efficacy of alternative pre‐plant burndown herbicide treatments as compared to glyphosate treatment, the industry standard in small grain production systems. Herbicide cost comparison and crop injury observation were also conducted. Most herbicide treatments provided ≥$ \ge $90% control of the predominant weed species at 3 weeks after herbicide application. At least six different herbicide treatments had an equivalent cost to that of glyphosate at $26.50 ha−1. No observable damage from herbicide treatments was observed and crop yield was not affected by the treatments. These factors indicate that there are alternatives to pre‐plant burndown herbicides that are equally effective as glyphosate. With combinations of herbicides, each having a different site of action, weed control can be achieved while simultaneously reducing the risk of herbicide resistance. Core Ideas: Alternatives to glyphosate for pre‐plant weed control would reduce overreliance on glyphosate.Alternative herbicides to glyphosate provided ≥90% control of the predominant weed species.At least six different herbicide treatments were effective and had equivalent costs to glyphosate.No visible crop damage or yield reduction was observed from any of the herbicide treatments. [ABSTRACT FROM AUTHOR]

'GemCraft' (Reg. no CV‐379, PI 701910), is a two‐rowed spring malt barley (Hordeum vulgare L.) developed by the USDA‐ARS, Aberdeen, ID, in cooperation with the University of Idaho Agricultural Experiment Station, in 2023. The release is derived from the cross of 2B98‐5312/98Ab11993 and was advanced through the bulk pedigree method F1–F5. GemCraft has been tested at the USDA‐ARS, and all other cooperative trials, as line 2Ab08‐X05M010‐65. This cultivar has been tested across 32 location years under irrigated conditions and 13 location years in dryland conditions. GemCraft has shown similar yield to the current malting barley cultivar checks Voyager, Merit 57, M69, Conrad, and AC Metcalfe but has higher yield potential than 'CDC Copeland', M69, and 'Harrington' under irrigated conditions. In dryland trials, GemCraft has similar yield to the checks of Voyager and Conrad but higher yield than other checks. Malting quality evaluation results showed GemCraft has high extract, low protein, and competent values in other traits. All the evaluations suggested that GemCraft would be a good choice as a malting cultivar for craft brewers. Core Ideas: The cultivar is a two‐rowed spring malting barley.This cultivar is specifically developed for the craft brewing industry.The cultivar has great yield potential.Laboratory testing confirmed the good malting quality.Brewers Association tested the cultivar and concluded the satisfactory flavor to the craft brewers. [ABSTRACT FROM AUTHOR]

Malted barley (Hordeum vulgare L.) is a foundational ingredient for the brewing industry, providing functionality and flavor. Increasing demand for locally produced barley, supported by the craft brewing and malting industries, necessitates identifying environments and varieties to meet this demand. Therefore, we analyzed malt quality and quantified quality scores for adjunct (AQS) and all‐malt (AMQS) brewing for 12 barley genotypes grown at 11 locations in eastern Washington and Northern Idaho in 2017 and 2018. Genotype‐by‐environment interactions were identified for six out of nine of the malt quality traits. These included kernel plumpness, malt extract, diastatic power, α‐amylase, β‐glucan, and free amino nitrogen. Stability indices, including Eberhart and Russell's deviation from regression, simultaneous selection index, and mean of the relative performance of genotypic values were quantified. We identified genotypes that had high stability and high AQS (LCS Genie, LCS Odyssey, 12WA 120.14, 12WA 120.23, and GemCraft) or AMQS (LCS Odyssey, LCS Genie, Palmer, 11WA 107.36, 11WA 107.58). Significant correlations between rainfall and barley protein (r = −0.22, p < 0.001), and between barley protein and seven out of eight of the other malt quality traits, reveal important relationships that may influence malt quality. This study may aid producers in variety selection, and provides a detailed malt quality analysis, evidence of G×E interactions, and stability measures for barley genotypes within a production region that has the potential to meet malting barley demand. Core Ideas: Protein content had significant correlations with seven out of eight of the malt quality traits.Genotype × environment interactions influenced six out of nine of the malt quality traits.We recommend Genie and Odyssey based on malt quality scores and stability. [ABSTRACT FROM AUTHOR]

Soil P testing is critical to ensure the accuracy of fertilizer recommendations and to optimize crop yield while minimizing negative environmental consequences. Olsen-P is the most commonly used soil P test for alkaline calcareous soils found in Idaho and the western United States. The Bray-1 test is commonly used in the Pacific Northwest on neutral to acidic soils but underestimates P in alkaline calcareous soils. Mehlich-3 has been evaluated throughout various regions in the United States. Few data evaluating Mehlich-3 exist for soils in the western United States. Additionally, the comparatively newly developed Haney–Haney–Hossner–Arnold (H3A) test, a component of the soil health tool, has not been widely evaluated on alkaline calcareous soils. Soil samples from the 0- to 30-cm depth were collected from agricultural fields throughout Idaho and analyzed with Bray-1, H3A, Mehlich-3, and Olsen-P extractants. The results indicate that Olsen-P was correlated with Mehlich-3, whereas Bray-1 and H3A were not correlated with Olsen-P. Both Bray-1 and H3A resulted in lower values of extractable P than the Olsen-P test, whereas Mehlich-3 resulted in greater values. A threshold point in CaCO3 (i.e., inorganic C) of 6.7 and 5.1 mg kg-1 for the Bray-1 and H3A was obtained, respectively, which indicated that inorganic C concentrations at or above these levels resulted in a reduction in extractable soil P. Thus Mehlich-3 could be evaluated for use in alkaline calcareous soils, whereas Bray-1 and H3A have notable issues that would limit their applicability. [ABSTRACT FROM AUTHOR]

The necrotrophic soilborne fungal pathogens Rhizoctonia solani AG8 and R. oryzae are principal causal agents of Rhizoctonia root rot and bare patch of wheat in dryland cropping systems of the Pacific Northwest. A 3-year survey of 33 parcels at 11 growers' sites and 60 trial plots at 12 Washington State University cereal variety test locations was undertaken to understand the distribution of these pathogens. Pathogen DNA concentrations in soils, quantified using real-time polymerase chain reaction, were correlated with precipitation, temperature maxima and minima, and soil texture factors in a pathogen-specific manner. Specifically, R. solani AG8 DNA concentration was negatively correlated with precipitation and not correlated with temperature minima, whereas R. oryzae concentration was correlated with temperature minima but not with precipitation. However, both pathogens were more abundant in soils with higher sand and lower clay content. Principal component analysis also indicated that unique groups of meteorological and soil factors were associated with each pathogen. Furthermore, tillage did not affect R. oryzae but affected R. solani AG8 at P = 0.06. Lower soil concentrations of R. solani AG8 but not R. oryzae occurred when the previously planted crop was a broadleaf (P < 0.05). Our findings showed that R. solani AG8 concentrations were consistent with the general distribution of bare patch symptoms, based on field observations and surveys of other pathogens, but was present at many sites in which bare patch symptoms were not evident. Management of Rhizoctonia root rot and bare patch should account for the likelihood that each pathogen is affected by a unique group of agroecological variables. [ABSTRACT FROM AUTHOR]

The article offers information on a study regarding the molecular identification and quantification of Pythium species. It reports that Pythium can be easily classified based on the morphology of their asexual and sexual structures. It reports that Pythium have unique shape of the sporangia and ornamentation of the oogonia. It informs that the species can be identified by sequencing specific loci and sequence alignments using a reference database.

The article presents a study on the extraction of Pythium and Rhizoctonia DNA from wheat roots and soil samples with the use pressure cycling technology (PCT). The PCT was performed in a closed system in which it also reduces the shearing and heating of samples. It was reported that the effectiveness of PCT for three soils reveals that it will be advantageous for other hard-to-extract pathogen samples.

Fluorescent Pseudomonas spp. producing the antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) play a key role in the suppressiveness of some soils to take-all of wheat and other diseases caused by soilborne pathogens. Soils from side-by-side fields on the campus of North Dakota State University, Fargo, USA, which have undergone continuous wheat, continuous flax or crop rotation for over 100 years, were assayed for the presence of 2,4-DAPG producers. Flax and wheat monoculture, but not crop rotation, enriched for 2,4-DAPG producers, and population sizes of log 5.0 CFU g root−1 or higher were detected in the rhizospheres of wheat and flax grown in the two monoculture soils. The composition of the genotypes enriched by the two crops differed. Four BOX-PCR genotypes (D, F, G, and J) and a new genotype (T) were detected among the 2,4-DAPG producers in the continuous flax soil, with F- and J-genotype isolates dominating (41 and 39% of the total, respectively). In contrast, two genotypes (D and I) were detected in the soil with continuous wheat, with D-genotype isolates comprising 77% of the total. In the crop-rotation soil, populations of 2,4-DAPG producers generally were below the detection limit, and only one genotype (J) was detected. Under growth-chamber and field conditions, D and I genotypes (enriched by wheat monoculture) colonized the wheat rhizosphere significantly better than isolates of other genotypes, while a J-genotype isolate colonized wheat and flax rhizospheres to the same extent. This study suggests that, over many years of monoculture, the crop species grown in a field enriches for genotypes of 2,4-DAPG producers from the reservoir of genotypes naturally present in the soil that are especially adapted to colonizing the rhizosphere of the crop grown. [ABSTRACT FROM AUTHOR]

Compares several major real-time chemistries that have been used for the detection and quantification of soilborne plant pathogens. Advantages and limitations of the chemistries; Applications of real-time polymerase chain reaction to the diagnosis of plant pathogens in soil and plant samples; Factors that should be considered in relation to the chemistries' assay development functions.

Rhizoctonia root rot and bare patch, caused by Rhizoctonia solani anastomosis group (AG)-8 and R. oryzae, are chronic and important yield-limiting diseases of wheat and barley in the Inland Pacific Northwest (PNW) of the United States. Major gaps remain in our understanding of the epidemiology of these diseases, in part because multiple Rhizoctonia AGs and species can be isolated from the same cereal roots from the field, contributing to the challenge of identifying the causal agents correctly. In this study, a collection totaling 498 isolates of Rhizoctonia was assembled from surveys conducted from 2000 to 2009, 2010, and 2011 over a wide range of cereal production fields throughout Washington State in the PNW. To determine the identity of the isolates, PCR with AG- or species-specific primers and/or DNA sequence analysis of the internal transcribed spacers was performed. R. solani AG-2-1, AG-8, AG-10, AG-3, AG-4, and AG-11 comprised 157 (32%), 70 (14%), 21 (4%), 20 (4%), 1 (0.2%), and 1 (0.2%), respectively, of the total isolates. AG-I-like binucleate Rhizoctonia sp. comprised 44 (9%) of the total; and 53 (11%), 80 (16%), and 51 (10%) were identified as R. oryzae genotypes I, II, and III, respectively. Isolates of AG-2-1, the dominant Rhizoctonia, occurred in all six agronomic zones defined by annual precipitation and temperature within the region sampled. Isolates of AG-8 also were cosmopolitan in their distribution but the frequency of isolation varied among years, and they were most abundant in zones of low and moderate precipitation. R. oryzae was cosmopolitan, and collectively the three genotypes comprised 37% of the isolates. Only isolates of R. solani AG-8 and R. oryzae genotypes II and III (but not genotype I) caused symptoms typically associated with Rhizoctonia root rot and bare patch of wheat. Isolates of AG-2-1 caused only mild root rot and AG-I-like binucleate isolates and members of groups AG-3, AG-4, and AG-11 showed only slight or no discoloration of the roots. However, all isolates of AG-2-1 caused severe damping-off of canola, resulting in 100% mortality. Isolates of Rhizoctonia AG-8, AG-2-1, AG-10, AG-I-like binucleate Rhizoctonia, and R. oryzae genotypes I, II, and III could be distinguished by colony morphology on potato dextrose agar, by PCR with specific primers, or by the type and severity of disease on wheat and canola seedlings, and results of these approaches correlated completely. Based on cultured isolates, we also identified the geographic distribution of all of these Rhizoctonia isolates in cereal-based production systems throughout Washington State. [ABSTRACT FROM AUTHOR]

Organic vegetable production accounted for 19% of the total organic acreage in Washington State in 2013, with 1,700 ha of certified organic vegetable pea. However, production is challenged constantly with the threat of poor emergence after planting due to damping-off caused by Pythium spp. A survey of Pythium spp. in organic vegetable production areas of the semiarid Columbia Basin of central Washington was carried out in fall 2009 to identify species associated with damping-off during early spring planting. Of 305 isolates baited from soil sampled from 37 certified organic fields, 264 were identified to 16 Pythium spp. by sequencing the internal transcribed spacer region of ribosomal DNA. A soil DNA-CFU regression curve was developed using real-time quantitative polymerase chain reaction assays for each of the three predominant pathogenic species (Pythium abappressorium, the P. irregulare complex, and P. ultimum var. ultimum) found in soil sampled from the 37 fields. The P. irregulare complex, P. abappressorium, and P. ultimum var. ultimum were detected in 57, 78, and 100% of the fields sampled, respectively. A regression analysis was used to determine that P. ultimum var. ultimum ranged from 14 to 332 CFU/g of soil in the 37 fields, the P. irregulare complex ranged from 25 to 228 CFU/g of soil, and P. abappressorium DNA was below the quantifiable limit. In summary, P. ultimum var. ultimum was the most prevalent pathogenic Pythium sp. detected in certified organic fields in the semiarid Columbia Basin of central Washington but multiple Pythium spp. may be associated with damping-off in cool and wet, early spring planting conditions. [ABSTRACT FROM AUTHOR]

Rhizoctonia bare patch and root rot disease of wheat, caused by Rhizoctonia solani AG-8, develops as distinct patches of stunted plants and limits the yield of direct-seeded (no-till) wheat in the Pacific Northwest of the United States. At the site of a long-term cropping systems study near Ritzville, WA, a decline in Rhizoctonia patch disease was observed over an 11-year period. Bacterial communities from bulk and rhizosphere soil of plants from inside the patches, outside the patches, and recovered patches were analyzed by using pyrosequencing with primers designed for 16S rRNA. Taxa in the class Acidobacteria and the genus Gemmatimonas were found at higher frequencies in the rhizosphere of healthy plants outside the patches than in that of diseased plants from inside the patches. Dyella and Acidobacteria subgroup Gp7 were found at higher frequencies in recovered patches. Chitinophaga, Pedobacter, Oxalobacteriaceae (Duganella and Massilia), and Chyseobacterium were found at higher frequencies in the rhizosphere of diseased plants from inside the patches. For selected taxa, trends were validated by quantitative PCR (qPCR), and observed shifts of frequencies in the rhizosphere over time were duplicated in cycling experiments in the greenhouse that involved successive plantings of wheat in Rhizoctonia-inoculated soil. Chryseobacterium soldanellicola was isolated from the rhizosphere inside the patches and exhibited significant antagonism against R. solani AG-8 in vitro and in greenhouse tests. In conclusion, we identified novel bacterial taxa that respond to conditions affecting bare patch disease symptoms and that may be involved in suppression of Rhizoctonia root rot and bare batch disease. [ABSTRACT FROM AUTHOR]