Search

The fungal infestation of crops can cause major economic losses. Toxins produced by the causative fungi (mycotoxins) represent a potential safety hazard to people and livestock consuming them. One such mycotoxin is deoxynivalenol (DON, also known as vomitoxin), a trichothecene associated with Fusarium Head Blight of wheat. DON is commonly found in cereal crops worldwide. A group of trichothecene mycotoxins closely related to DON, the NX toxins, have been reported to occur in the northeastern United States and southern Canada. While many commercial immunoassays are available to detect DON, there are no rapid screening assays for the NX toxins. We describe the development and isolation of three monoclonal antibodies (mAbs) specific towards two NX toxins: NX-2 and NX-3. The mAbs did not recognize DON or several other closely related trichothecenes. One of the mAbs was selected for development of an enzyme-linked immunosorbent assay (ELISA) for NX-2 and NX-3 in wheat. The dynamic ranges for the assay were 7.7 to 127 μg/kg for NX-2 and 59 μg/kg to 1540 μg/kg for NX-3 in wheat. Recoveries from spiked wheat averaged 84.4% for NX-2 and 99.3% for NX-3, with RSDs of 10.4% and 11.3%, respectively (n = 24). The results suggest that this assay can be used to screen for NX toxins in wheat at levels relevant to human food and animal feed safety. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is primarily caused by Fusarium graminearum and is the most destructive wheat disease in western Canada. The trichothecene toxin deoxynivalenol (DON) and its derivatives 3-ADON and 15-ADON, which are produced by Fusarium, are toxic to humans and livestock. This study aimed to evaluate the Fusarium species and trichothecene-producing genotypes present in producer wheat fields of western Canada in 2019 and 2020. The grain analysis for DON showed that samples collected from both years experienced mild levels of FHB toxin contamination. In spring wheat, the highest mean DON content was recorded from Saskatchewan samples (0.9 ppm) in 2019 and Manitoba samples (0.3 ppm) in 2020. Winter wheat samples had lesser mean DON levels (<0.2 ppm) for all three provinces in both years. The chaff collected from the same spring wheat heads showed a significantly higher DON content than the grain in both years (P < 0.1 for 2019 and P < 0.001 for 2020), suggesting that chaff should be tested for DON before use as livestock feed. Most samples collected were infected by F. graminearum, with the highest F. graminearum percentage observed in the spring wheat from Manitoba. Further, F. avenaceum, F. sporotrichoides, F. culmorum, F. poae and F. acuminatum were found in infected samples. Most of the F. graminearum isolates were of the 3ADON genotype, which is the dominant genotype in FHB disease in western Canada. The study indicated that 3ADON-producing F. graminearum is becoming more frequent in western Canadian fields than the 15ADON genotype. [ABSTRACT FROM AUTHOR]

Summary: Glyphosate‐resistant wheat plants were discovered in southern Alberta in 2017, representing an unauthorized GM release in Canada. The Canadian Food Inspection Agency undertook a series of experiments to characterize and identify this unknown GM wheat, as well as to develop and validate construct‐specific and event‐specific qPCR assays. Results of PCR‐based assays and Sanger sequencing indicated the presence of CaMV 35S promoter (p35S), Rice Actin 1 intron (RactInt1), CP4‐EPSPS gene and nopaline synthase terminator (tNOS) elements in the unknown GM wheat. Genome walking and bead capture strategies, combined with high‐throughput sequencing, were used to identify the 5′ and 3′ wheat junctions and the subsequent mapping of the insert to chromosome 3B of the wheat genome. A probable transformation vector, pMON25497, was recognized, and further testing identified the unknown GM wheat as MON71200 event, one of two events obtained with the pMON25497 vector. The two construct‐specific assays targeted the junctions of the RactInt1 and the CP4‐EPSPS elements and the CP4‐EPSPS and tNOS elements, while the event‐specific assay was located at the 3′ junction into the wheat genome. Both construct‐specific and event‐specific assays had limits of detection of 0.10% of MON71200 in a seed pool. As expected, the two construct‐specific assays cross‐reacted with other wheat and corn events containing the same elements in the same order. No cross‐reactivity was observed for the event‐specific assay. The integrated strategy employed in this study can serve as a model for other cases when facing similar challenges involving unknown GM events. [ABSTRACT FROM AUTHOR]

Wheat market integration between the US and the UK before the "first era of globalization" (in the second half of the nineteenth century) was frequently interrupted by policy and "exogenous" events such as wars. This paper adds Canada to this story by looking at trade and price data, as well as contemporary debates. This allows us to triangulate the role of policy and wars, since Canada as a small open economy was part of the British Empire. We find that, despite its privileged access to British markets, Canada faced similar barriers to the US, suggesting that membership of the British Empire provided only a modest benefit to trade. We also describe the limitations she faced accessing the US market, in particular after American independence. [ABSTRACT FROM AUTHOR]

The potential for healthier consumer food substitutions is an important factor in the study of food environments, dietary choices, and population nutrition promotion. The burden of diet-related non-communicable diseases is unevenly distributed across Canada and variation in the food environment sub-nationally may be an important explanation. We used population-based 24 h dietary recall data from the 2015 Canadian Community Health Survey—Nutrition for Canadian adults (n = 13 919) to examine dietary intakes of two food group pairings (whole grains/refined grains and legumes/red meats) where consumer substitutions have been recognized to be of importance in promoting healthy and sustainable population diet. We used an ANOVA followed by pairwise comparisons with Bonferroni correction to estimate differences in intakes between provinces for daily weight and proportion of total energy consumed. Based on the Global Burden of Disease Study, Canadians consumed below the average daily requirements of legumes and whole grains and well above the required range of red meat, suggesting room for broad improvements to population diet. Findings also demonstrate that there is potential for targeted shifts in dietary intakes among non-consumers of certain foods (e.g., legumes). This study may inform intervention development for the consumer nutrition environment including food accessibility and affordability to reduce non-communicable disease risk. [ABSTRACT FROM AUTHOR]

The article emphasizes the need for expanding the differential sets used in race typing experiments for plant pathologists to provide valuable information to plant breeders. Specifically focusing on stripe rust, a fungal disease that affects wheat crops, the article explains how the pathogen evolves and gains virulence over time, necessitating the continuous introgression of resistance from different sources. The article also highlights the importance of including relevant differential genotypes in race typing experiments to support the development of resistant cultivars. Additionally, the document provides a list of wheat cultivars and their corresponding resistance genes to stripe rust, along with discussing the significance of standardizing race typing conditions for more accurate and comparable results in studying the population dynamics of the stripe rust pathogen in North America. [Extracted from the article]

Amending soil with manure from cattle fed biochar (BC) (biochar–manure [BM]) is a potential best management practice to improve plant nutrition in the circular economy. Yet, information concerning the agronomic performance of BM under temperate field conditions is scarce. A 2‐year study on a Gray Luvisol was conducted to determine the effect of BM on the crop growth of spring wheat (Triticum aestivum L.), followed by canola (Brassica napus L.), soil fertility, and microbial function. Treatments included (i) no amendments (control), (ii) BC at 5 and 10 Mg·ha−1 (BC5 and BC10), (iii) regular stockpiled manure (RM) at 100 kg total N·ha−1, (iv) stockpiled BM at 100 kg total N·ha−1, and (v) BC and RM (BC+RM) or BC and BM (BC+BM) at the aforementioned rates. During the wheat growing season in 2020, which had high precipitation, grain yield was 2.4 times greater in BM+BC10 than in BM alone (1416 vs. 579 kg·ha−1, p < 0.001), highlighting synergistic effects of BM together with BC application on agronomic performance. Conversely, lower precipitation and warmer temperatures in the canola growing season in 2021 hampered any statistical differences among treatments. While soil microbial biomass did not change by the end of the experiment, shifts toward amino acid utilization with BC additions in both crops potentially influenced crop growth and nitrogen‐use efficiency. In summary, BM+BC at 10 Mg·ha−1 performed best in this study during the first cropping season under cold and rainy conditions. Core Ideas: Biochar and biochar–manure additions increased wheat production.There were shifts toward amino acid utilization with biochar additions.Precipitation and temperature played an essential part in level of biochar addition benefits. [ABSTRACT FROM AUTHOR]

The reemergence and spread of Xanthomonas translucens, the causal agent of bacterial leaf streak in cereal crops and wilt in turfgrass and forage species, is a concern to growers in the United States and Canada. The pathogen is seedborne and listed as an A2 quarantine organism by EPPO, making it a major constraint to international trade and exchange of germplasm. The pathovar concept of the X. translucens group is confusing due to overlapping of plant host ranges and specificity. Here, comparative genomics, phylogenomics, and 81 up-to-date bacterial core gene set (ubcg2) were used to assign the pathovars of X. translucens into three genetically and taxonomically distinct clusters. The study also showed that whole genome-based digital DNA-DNA hybridization unambiguously can differentiate the pvs. translucens and undulosa. Orthologous gene and proteome matrix analyses suggest that the cluster consisting of graminis, poae, arrhenatheri, phlei, and phleipratensis is very divergent. Whole-genome data were exploited to develop the first pathovar-specific TaqMan real-time PCR tool for detection of pv. translucens on barley. Specificity of the TaqMan assay was validated using 62 Xanthomonas and non-Xanthomonas strains as well as growth chamber-inoculated and naturally infected barley leaves. Sensitivity levels of 0.1 pg (purified DNA) and 23 CFUs per reaction (direct culture) compared favorably with other previously reported real-time PCR assays. The phylogenomics data reported here suggest that the clusters could constitute novel taxonomic units or new species. Finally, the pathovar-specific diagnostic tool will have significant benefits to growers and facilitate international exchange of barley germplasm and trade. [ABSTRACT FROM AUTHOR]

The occurrence of two types of cultivars of spring bread wheat of Canada that differ in their necrotic genotypes was shown. The cultivars of one type had the ne1ne1Ne2Ne2 genotype, and the cultivars of the second type had the ne1ne1ne2ne2 genotype. The Ne1Ne1ne2ne2 genotype was not found. The Ne2 genes were represented by alleles of medium strength, ms, and strong alleles, s. By pedigree analysis, the donors of the Ne2 gene were identified. [ABSTRACT FROM AUTHOR]

Stripe rust (Puccinia striiformis f. sp. tritici (Pst)) and powdery mildew (Blumeria graminis f. sp. tritici (Bgt)) are important diseases of wheat in Canada and worldwide. Molecular detection methods permit spore detection of few spores; therefore, there is a need to determine initial inoculum thresholds for pathogens to cause disease under both controlled environments and in the field. Susceptible wheat cultivars 'Avocet' and 'AC Barrie' were inoculated with different quantities of spores (0, 103, 104, 105, 106, and 107) of Pst and Bgt. Disease incidence, severity and infection type were evaluated. Results of controlled environment studies showed that the minimum number of spores necessary to cause appreciable incidence and severity for Pst was at higher spore concentrations of 105–106 spores. Conversely, low incidence and severity levels were observed at 103–104 spores for Bgt. Despite occurrence of natural Pst infection, results of field studies in 2016 and 2017 in Southern Alberta demonstrated that significant increases in severity levels were observed following application of 1.2 × 107 spores. Collectively, these results demonstrated that stripe rust severities increased with increasing spore concentration only at high spore levels. In contrast, Bgt severity increased with spore concentration from 103 to 107 spores mL−1. In vitro and in vivo spore germination tests demonstrated germination rates of Pst spores were reduced at lower spore concentrations compared to germination rates at the higher concentrations. Understanding of minimum spore numbers required for disease development will be a prerequisite for predicting epidemics and devising fungicide control measures for future sustainable agricultural systems. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is a devastating disease of wheat in Canada and disease surveillance is a critical component of integrated disease management, disease forecasting, prioritizing research and breeding efforts, grain handling, and cleaning post harvest. We report on the recent trends of FHB in Canadian wheat including incidence and severity from 1995 to 2021 based on data from 208,247 samples. Our results show a steady increase in FHB incidence from 1995, with an epidemic year in 2016, followed by several years of low incidence. Results also indicated that FHB severity has been stable over time, but not always correlated with incidence. Data from the analysis of 26,538 samples from 2018 to 2021 demonstrate a strong positive correlation between the number of Fusarium damaged kernels (severity) and concentrations of the mycotoxin deoxynivalenol. Together, our results provide the most robust survey of FHB in Canada to date, which complement national and international disease monitoring and management efforts. [ABSTRACT FROM AUTHOR]

Land suitability models for Canada are currently based on single-crop inventories and expert opinion. We present a data-driven multi-layer perceptron that simultaneously predicts the land suitability of several crops in Canada, including barley, peas, spring wheat, canola, oats, and soy. Available crop yields from 2013–2020 are downscaled to the farm level by masking the district level crop yield data to focus only on areas where crops are cultivated and leveraging soil-climate-landscape variables obtained from Google Earth Engine for crop yield prediction. This new semi-supervised learning approach can accommodate data from different spatial resolutions and enables training with unlabelled data. The incorporation of a crop indicator function further allows for the training of a multi-crop model that can capture the interdependences and correlations between various crops, thereby leading to more accurate predictions. Through k-fold cross-validation, we show that compared to the single crop models, our multi-crop model could produce up to a 2.82 fold reduction in mean absolute error for any particular crop. We found that barley, oats, and mixed grains were more tolerant to soil-climate-landscape variations and could be grown in many regions of Canada, while non-grain crops were more sensitive to environmental factors. Predicted crop suitability was associated with a region's growing season length, which supports climate change projections that regions of northern Canada will become more suitable for agricultural use. The proposed multi-crop model could facilitate assessment of the suitability of northern lands for crop cultivation and be incorporated into cost-benefit analyses. [ABSTRACT FROM AUTHOR]

This work investigates the effectiveness of solar heating using clear polyethylene bags against rice weevil Sitophilus oryzae (L.), which is one of the most destructive insect pests against many strategic grains such as wheat. In this paper, we aim at finding the key parameters that affect the control heating system against stored grain insects while ensuring that the wheat grain quality is maintained. We provide a new benchmark dataset, where the experimental and environmental data was collected based on fieldwork during the summer in Canada. We measure the effectiveness of the solution using a novel formula to describe the amortising temperature effect on rice weevil. We adopted different machine learning models to predict the effectiveness of our solution in reaching a lethal heating condition for insect pests, and hence measure the importance of the parameters. The performance of our machine learning models has been validated using a 10-fold cross-validation, showing a high accuracy of 99.5% with 99.01% recall, 100% precision and 99.5% F1-Score obtained by the Random Forest model. Our experimental study on machine learning with SHAP values as an eXplainable post-hoc model provides the best environmental conditions and parameters that have a significant effect on the disinfestation of rice weevils. Our findings suggest that there is an optimal medium-sized grain amount when using solar bags for thermal insect disinfestation under high ambient temperatures. Machine learning provides us with a versatile model for predicting the lethal temperatures that are most effective for eliminating stored grain insects inside clear plastic bags. Using this powerful technology, we can gain valuable information on the optimal conditions to eliminate these pests. Our model allows us to predict whether a certain combination of parameters will be effective in the treatment of insects using thermal control. We make our dataset publicly available under a Creative Commons Licence to encourage researchers to use it as a benchmark for their studies. [ABSTRACT FROM AUTHOR]

Resource selection informs understanding of a species' ecology and is especially pertinent for invasive species. Since introduced to Canada, wild pigs (Sus scrofa Linnaeus, 1978) remain understudied despite recognized negative impacts on native and agricultural systems globally. Elsewhere in North America, pigs typically use forests and forage in agricultural crops. We hypothesized Canadian wild pigs would behave similarly, and using GPS locations from 15 individuals, we examined diel and seasonal resource selection and movement in the Canadian prairie region. Forests were predominately selected during the day, while corn (Zea mays L.), oilseeds, and wheat (Triticum aestivum L.) were predominately selected at night. Forests and corn were consistently selected throughout the growing season. Wetlands and forests showed greater use rates than other habitats, with evident trade-offs as crop use increased with the timing of maturation. Activity was consistent with foraging in growing crops. Results indicate diel patterns were likely a function of short-term needs to avoid daytime anthropogenic risk, while seasonal patterns demonstrate how habitats that fill multiple functional roles — food, cover, and thermoregulation — can be optimized. Understanding selection by invasive species is an important step in understanding their potential environmental impacts in novel environments and informs their management. [ABSTRACT FROM AUTHOR]

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating disease of wheat (Triticum aestivum L.). Deployment of resistant wheat cultivars is one of the best strategies to mitigate disease‐associated risks. The genotype P2711 possesses effective stripe rust resistance under field conditions in western Canada, however, the genetic basis of this resistance is unknown. To identify resistance, a recombinant inbred line (RIL) population comprised of 252 RILs was developed from the cross AAC Cameron/P2711. This population was evaluated for stripe rust severity at the adult plant stage in Creston, BC (in 2018, 2019, and 2020) and Lethbridge, AB (in 2018 and 2020), and was genotyped using the wheat 90K iSelect single nucleotide polymorphism (SNP) assay. A high‐density genetic map comprised of 8,915 markers was constructed covering all the wheat chromosomes. Four resistance quantitative trait loci (QTLs) were contributed by P2711 and three from AAC Cameron. QYr.lrdc‐2A.1, corresponding to the Yr17 gene, was the most stable QTL and detected in four out of five environments, whereas QYr.lrdc‐2B was the second most stable QTL. These two QTL along with QYr.lrdc‐5A showed a significant reduction in stripe rust severity when present together. Where most of the QTLs detected in both locations, QYr.lrdc‐1A.1 and QYr.lrdc‐1A.2, both were detected only in Creston, BC. Stable QTLs on chromosome 2A, 2B, and 5A, and their closely associated markers identified in this study could be utilized in marker‐assisted selection for stripe rust resistant cultivar development. Core Ideas: This study discovered seven stripe rust resistance quantitative trait loci (QTLs) in AAC Cameron/P2711 recombinant inbred line population.QTLs identified on chromosomes 2A, 2B, and 5A were the three most stable and effective QTLs.QTL of chromosome 2A is conditioned by the presence of Yr17 gene in P2711.We have identified a novel QTL QYr.lrdc‐5A for stripe rust resistance from resistant parent P2711. [ABSTRACT FROM AUTHOR]

Previous genome‐wide association studies in Canadian spring wheat (Triticum aestivum L.) cultivars were based on consensus linkage maps of small population sizes. Here, we used a panel of 192 spring wheat cultivars widely used in western Canada to (a) explore the allelic variation and effects of six known genes and (b) identify genomic regions associated with eight agronomic traits and grain characteristics using the International Wheat Genome Sequencing Consortium (IWGSC) RefSeq v2.0 map. The panel was evaluated for heading, maturity, plant height, lodging, grain yield, grain protein content, test weight, and kernel weight under four conventionally (high N) and three organically (low N) managed environments and genotyped with the wheat 90K single‐nucleotide polymorphism (SNP) array of which 23,342 SNPs were polymorphic. Using gene‐specific functional markers, the proportion of homozygous genotypes with favorable alleles was low for Fhb1 (7–8%), Rht‐D1 (14%), and Rht‐B1 (18%); moderate for Lr34/Yr18 (28–39%); and high for Glu‐A1 (78%) and Glu‐D1 (85%). We identified a total of 172 SNPs located at 94 genomic regions across 19 chromosomes of which 82 regions were associated with a single trait and 12 regions coincided with two to three traits. Twenty‐seven of the 94 regions (28%) were common between the conventional and organic managements systems; the remaining were management specific. Two of the identified regions on chromosome 5A (586.5–588.6 Mb) and 5B (575.8 Mb) coincided with the vernalization response Vrn‐A1 and Vrn‐B1 genes, respectively. The IWGSC RefSeq v2.0 physical positions presented here would serve as the basis for easily comparing independent discovery studies in the future. Core Ideas: The allelic variation and effects of six known genes in a panel of historical and modern Canadian spring wheat were investigated.The effect of low and high nitrogen management systems on QTL detection were compared using eight phenotypic traits.Some coincident genomic regions associated with negatively correlated traits were uncovered.The IWGSC RefSeq v2.0 physical map of 23,342 of the wheat 90K SNP array presented here would serve as a basis for comparing QTL results. [ABSTRACT FROM AUTHOR]

This study was conducted to identify and map stem rust resistance genes in Canada Western Red Spring (CWRS) wheat variety 'AAC Prevail' and elite line 'BW961ʹ. A population of 227 doubled haploid lines from 'AAC Prevail'/'BW961ʹ and parents were evaluated for their response to stem rust (Puccinia graminis) at Njoro, Kenya, from 2016–2019 and genotyped using a targeted genotyping by sequencing SeqSNP assay. 'AAC Prevail' and 'BW961ʹ were susceptible to race TTKSK in seedling tests in Canada. We identified stable QTL (significant in most environments tested) associated with field stem rust resistance on chromosome arms 2BS and 7AL, and minor QTL on 5AL, 6AS and 7BL. The QTL on 5AL, 7AL and 7BL were contributed by 'AAC Prevail', while those on 2BS and 6AS were contributed by 'BW961ʹ. The QTL on 7AL was detected across all environments and explained 9.5% to 39% of the variation in disease severity (DS) and infection response (IR). The QTL on 2BS was associated with DS in all environments and in three of four environments for IR, and explained 4.8% to 12% of the variation in DS and IR. In two environments, the combination of 2BS and 7AL significantly enhanced field stem rust resistance compared with either QTL singly. Using SNP markers closely linked to the novel QTL on 2BS and 7AL, Kompetitive Allele Specific PCR markers were developed and validated in the population. These results provide breeders with new information and markers to utilize these sources of stem rust resistance. [ABSTRACT FROM AUTHOR]

Wheat leaves infected with Puccinia triticina, the causal agent of wheat leaf rust, were collected annually throughout Canada from 2015 to 2019. There were 47, 75, 44, 38 and 54 different virulence phenotypes, respectively, found annually, representing 154 unique virulence phenotypes. From Alberta, there were three virulence phenotypes, MBDS, TDBJ, and TDBS, found in 2015 and eight in 2019, the most common being MBDS and TNBJ (both 20%). The most common virulence phenotypes found in Manitoba and Saskatchewan were MBDS (17.8%) and TNBG (16.3%) in 2015, MNPS (17.2%) and MBDS (15.9%) in 2016, MNPS (41.9%) and TBBG (17.2%) in 2017, MNPS (35.3%) and TBBG (34.8%) in 2018, and MNPS (54.7%) and MBDS (10.7%) in 2019. In Ontario, the most common virulence phenotypes found were MBTN (25%) and MBDS (16.7%) in 2015, MCQQ (13.6%) in 2016, MBTN (33.3%) and PBDG (19.0%) in 2017, TFPJ (13.6%) in 2018, and MCTN (14.5%) and MBTN (10.9%) in 2019. In Quebec the most common virulence phenotypes found were TBBG (66.7%) and MLDS (33.3%) in 2015, TCGJ (23.1%) and MBTN (15.4%) in 2017, MCQH (26.3%) and FCPT (21.1%) in 2018, and MBTN and MCRS (both 18.2%) in 2019. The frequencies of virulence varied on all resistance genes over these years. Within Canada, virulence on Lr21 peaked in 2018 at 39.9% and then declined in 2019, with a similar trend noticed for virulence on Lr2a and Lr2c. There was no virulence detected on Lr19, Lr29, Lr32, Lr52, and Lr22a, while virulence on Lr25 was rare. [ABSTRACT FROM AUTHOR]

Representative subsets of global climate models (GCMs) are often used in climate change impact studies to account for uncertainty in ensemble climate projections. However, the effectiveness of such subsets has seldom been assessed for the estimations of either the mean or the spread of the full ensembles. We assessed two different approaches that were employed to select 5 GCMs from a 20-member ensemble of GCMs from the CMIP5 ensemble for projecting canola and spring wheat yields across Canada under RCP 4.5 and 8.5 emission scenarios in the periods 2040–2069 and 2070–2099, based on crop simulation models. Averages and spreads of the simulated crop yields using the 5-GCM subsets selected by T&P and KKZ approaches were compared with the full 20-GCM ensemble. Our results showed that the 5-GCM subsets selected by the two approaches could produce full-ensemble means with a relative absolute error of 2.9–4.7% for canola and 1.5–2.2% for spring wheat, and covers 61.8–91.1% and 66.1–80.8% of the full-ensemble spread for canola and spring wheat, respectively. Our results also demonstrated that both approaches were very likely to outperform a subset of randomly selected 5 GCMs in terms of a smaller error and a larger range. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) has a negative impact on cereal food safety, quality and yield. The majority of FHB resistance genes in wheat (Triticum spp.) have been identified based on reaction to Fusarium graminearum, which, in Canada, has two prevalent trichothecene chemotypes, 3-acetyl-deoxyinvalenol (ADON) and 15-ADON. Three hexaploid (Triticum aestivum L.) and four tetraploid (Triticum turgidum L. ssp. durum and Triticum turgidum L. spp. dicoccoides (Korn. ex Asch. & Graebn.) Thell.) wheat genotypes with different genes for resistance and with different reactions to F. graminearum were evaluated in replicated greenhouse trials to determine if the resistance genes currently deployed in Canadian wheat are effective against both the 3-ADON and 15-ADON chemotypes. The development of FHB was rated as disease severity. The genotypes showed differential responses, with a higher level of disease development in the hexaploid wheat genotypes inoculated with the 3-ADON than with the 15-ADON chemotype. The opposite was observed in the tetraploid wheat genotypes. Tetraploid genotype BGRC3487 and a hexaploid genotype ND2710 showed similar resistance to both 3-ADON and 15-ADON chemotypes. These would be effective sources to breed lines resistant to both 3-ADON and 15-ADON chemotypes and reduce FHB risk. [ABSTRACT FROM AUTHOR]

The production of biofuels is limited in Canada, but the availability of wheat straw as a second‐generation (i.e., cellulosic) feedstock is an exciting prospect for the future development of a biofuel industry. The future success of such a biofuel industry will depend on future ethanol prices and prices related to wheat straw. These prices are likely to be influenced by markets related to the existing first‐generation ethanol industry in the United States. Therefore, the motivation of this paper is to investigate relationships between Canadian wheat prices and US corn, ethanol, and gasoline prices. We employ a DCC‐MGARCH enhanced VEC model to investigate time‐varying relationships among these markets. Results indicate that there are positive relationships between wheat and corn, ethanol and corn, and wheat and ethanol markets. Our results add to a better understanding of the level of integration between select Canadian agricultural markets and US energy markets. More specifically, the price relationships identified highlight several sources of price risk that may affect the financial success of commercially producing second‐generation ethanol from wheat straw in Canada. This information will be of particular interest to prospective industry investors and policymakers. [ABSTRACT FROM AUTHOR]

Wheat is affected by many fungal diseases that can cause severe yield and quality losses. Disease prediction models generally employ weather data to estimate potential for infection to determine timing for fungicide applications, but these models fail to account for the presence and quantity of pathogen inoculum. This study adapted highly specific qPCR primers to identify and quantify, in real-time, inoculum present in air for the six most important wheat pathogens in Canada. Fungal spores were collected using either Burkard spore collectors and quantified using qPCR or microscope slides covered with adhesive tape and identified and quantified using microscopy. Samples were collected from seven different sites in southern Alberta throughout the 2015–2017 growing seasons. The results demonstrated that qPCR can reliably identify and quantify spores from Puccinia striiformis f. sp. tritici, P. triticina, P. graminis f. sp. tritici, Blumeria graminis f. sp. tritici, Pyrenophora tritici-repentis, and Fusarium graminearum. The limits of detection of DNA for primer pairs in singleplex tests ranged from 0.0001 ng for P. graminis to 0.001 ng for P. tritici-repentis, which corresponded to approximately 3 spores for P. tritici-repentis and F. graminearum and 1 spore for the other pathogens. Conversely, microscopy permitted identification of rusts to the genus but not to the species level and was ineffective in quantification of the remainder of the wheat pathogens. This study will contribute to the development of a fast and reliable forecasting system that will enable identification and quantification of airborne pathogens in real-time before initial disease symptoms appear. [ABSTRACT FROM AUTHOR]

Stem rust, caused by Puccinia graminis, is a catastrophic disease that has and continues to cause yield losses in barley, oat, and wheat crops worldwide. Use of host resistance genes is the most economic, efficient, and environmentally best method to control the disease. Resistance genes have been incorporated into most commercial cultivars and have been effective, for races in the North American populations of P. graminis. However, new races of stem rust are constantly emerging and therefore it is imperative to monitor the virulence structure in the populations to detect new races with increased virulence. Stem rust samples were collected in 2013 and 2014 in Manitoba, Ontario, Quebec, and Saskatchewan to determine the incidence and severity of stem rust in barley (Hordeum vulgare), oat (Avena sativa), and wheat (Triticum aestivum) fields and to characterize the virulence dynamics in the pathogen populations. No stem rust was found in cultivated wheat, and incidence was at trace (<1%) levels in barley fields and very low (0–5%) levels in oat fields in 2013 and 2014. In wheat trap plots and collections from barley, race QFCSC of P. graminis f. sp. tritici was dominant in 2013 (85.9%) and was the only race found in 2014. Races MCCFC, QTHJF, RFCSC, RKQSC, and TMRTF were at low (<5%) levels in 2013. From collections in oat fields and stands of wild barley, nine races of P. graminis f. sp. avenae were found in 2013, with TJS (56.9%) and TJJ (23.5%) the most frequent. In 2014, we found only six races and TJS (74.5%) and TJJ (19.1%) were the most frequent. No new races of stem rust were detected in Canada in 2013 or 2014. [ABSTRACT FROM AUTHOR]

Parastagonospora nodorum is an important fungal pathogen that causes Septoria nodorum blotch (SNB) in wheat. This pathogen produces several necrotrophic effectors that act as virulence factors; three have been cloned, SnToxA, SnTox1, and SnTox3. In this study, P. nodorum and its sister species P. avenaria f. tritici (Pat1) were isolated from wheat node and grain samples collected from distanced sites in western Canada during 2018. The presence of effector genes and associated haplotypes were determined by PCR and sequence analysis. An internal transcribed spacer-restriction fragment length polymorphism test was developed to distinguish between leaf spotting pathogens (P. nodorum, Pat1, Pyrenophora tritici-repentis, and Bipolaris sorokiniana). P. nodorum was mainly recovered from wheat nodes and to a lesser extent from the grains, while Pat1 was exclusively isolated from grain samples. The effector genes were present in almost all P. nodorum isolates, with the ToxA haplotype 5 (H5) being most prevalent, while a novel ToxA haplotype (denoted here H21) is reported for the first time. In Pat1, only combinations of SnTox1 and SnTox3 genes were present. A ToxA haplotype network was also constructed to assess the evolutionary relationship among globally found haplotypes to date. Finally, cultivars representing wheat development in Canada for the last century were tested for sensitivity to Sn-effectors and to the presence of Tsn1, the ToxA sensitivity gene. Of tested cultivars, 32.9 and 56.9% were sensitive to SnTox1 and SnTox3, respectively, and Tsn1 was present in 59% of the cultivars. In conclusion, P. nodorum and Pat1 were prevalent wheat pathogens in Canada with a potential tissue-specific colonization capacity, while producing necrotrophic effectors to which wheat is sensitive. [ABSTRACT FROM AUTHOR]

Aims: At present, there is an increasing demand for plant-based proteins due to their nutritional values and beneficial effect to the environment. Improving the availability of plant protein enriched foods would be highly beneficial for the consumers to follow a healthy diet. Reformulating a commonly consumed product, such as bread, with plant-based protein will be a convenient option for the people to improve their protein intake. Therefore, the objective of this study was to determine the effect of protein isolate (pea and soy) on color, microscopic structure, sensory properties, and protein content in whole wheat bread. Methods: The experiments were conducted at the University of Guelph, ON, Canada. Seven whole wheat bread samples (control, P20, P30, P40, S20, S30 and S40) were prepared (n = 3 loaves for each treatment). Results: The RGB and LFNx01aFNx01bFNx01values of loaf (crust) and slice (crumb) of the control bread was higher than that of all protein enriched bread samples. The control bread had larger pores than the protein enriched samples. The pores in the pea protein isolate enriched bread were tightly packed while compared to soy protein. There was no difference in most of the sensory attributes between control and S20 breads. In terms of softness, all protein blended breads scored lower than the control. Fifty percentage of the panelists chose S20 as their first choice, whereas only thirty percent selected control as their first choice. The protein content of the bread samples was 8.9, 15.4, 18.1, 20.7, 15.9, 18.6 and 20.9%, for control, P20, P30, P40, S20, S30 and S40, respectively. Conclusion: Soy protein isolate has more opportunities than pea protein isolate to incorporate with whole wheat flour, and produce acceptable bread. [ABSTRACT FROM AUTHOR]

Canada is one of the largest wheat producers in the world, and wheat is grown over an area spanning most of the southern latitudes, with the prairie region (provinces of Saskatchewan, Alberta, and Manitoba) being the main producer. Several pathogens and pests attack wheat, but at present fusarium head blight (FHB), stripe rust, and leaf spots are the most damaging diseases to wheat production in Canada. Historically, smuts, stem rust, and leaf rust caused major crop losses in Canada and can still pose serious threat if management practices are relaxed. Cropping practices used by Canadian farmers to grow and harvest wheat over the last century have influenced disease development and pathogen biology, affecting the severity, incidence, and prevalence of crop diseases over time. Changes such as reduced tillage coincide with emergence of residue‐borne diseases, such as FHB and leaf spots, while the deployment of resistant cultivars and increased fungicide use has resulted in the reduction of common bunt, stem, and leaf rust. This review will discuss the influence of long‐term cropping practices, alone or in combination, on the biology, emergence, and prevalence of wheat diseases in Canada over the last century. [ABSTRACT FROM AUTHOR]

The objectives of this study were to investigate the Fusarium damage-deoxynivalenol (FUS DMG-DON) relationship in various wheat growing locations in western Canada in 2016 and to compare the relationships to the Prairie-wide FUS DMG-DON assessment of that harvest year. Fusarium head blight was prevalent in spring wheat and durum grown in western Canada in 2016. Harvest survey samples for Canada Western Red Spring (CWRS) wheat and Canada Western Amber Durum (CWAD) were inspected for Fusarium damaged kernels, and analyzed using an enzyme-linked immunosorbent assay for the Fusarium-produced mycotoxin DON. For CWAD and most CWRS, there was a significant relationship between FUS DMG (represented as the mass percentage of Fusarium damaged kernels) and DON, whose presence is regulated in food products to minimize consumers' exposure. However, CWRS from south-central Alberta contained much lower DON than expected by the reported visual symptoms of FUS DMG of the samples. High throughput real-time PCR analysis showed that DON-producing Fusarium species were associated with less than 40% of the Fusarium damaged kernels in the CWRS. This was different from what was observed with CWAD grown in the same area in 2016. Multi-mycotoxin analysis by liquid chromatography with tandem mass spectrometry did not show an increased presence of mycotoxins produced by other Fusarium species, and therefore suggested that the observed damage in CWRS from south-central Alberta was not caused by Fusarium species. [ABSTRACT FROM AUTHOR]

The assessment of drought characteristics often depends on drought indices, geographic location, hydro‐climatic condition, and timescale. In this study, we examined the spatiotemporal characteristics of drought events using the Standardized Precipitation Evapotranspiration Index (SPEI) and the Multivariate Standardized Drought Index (MSDI). We developed a novel framework using hydro‐climatic variables from a high‐resolution process‐based hydrologic model to understand factors that alter drought indices at various timescales, and their impact on crop yields in a large agricultural region of western Canada. These indices were used to quantify droughts for each month of the year by examining 1–12‐month drought timescales in 2255 sub‐basins, simulated in 17 main river basins across Alberta, for 1981–2017. Temporal variations of the Standardized Yield Residuals Series (SYRS) of three major cereal crops (spring wheat, barley, and canola) were analysed for 1981–2017. Drought characteristics resulting from two indices varied due to differences in the input variables and timescales. The MSDI‐based results showed more frequent droughts during the fall and winter for shorter timescales, while the SPEI‐based results showed more during spring and summer. Comparing drought frequencies at the decadal scale, we found more droughts during 1996–2005 than during 1986–1995 and 2006–2015. The spatial evolution of drought events based on the MSDI showed more sub‐basins with increasing dryness during the study period than did results from the SPEI. The relationship between detrended drought indices and the SYRS varied depending on timescale, geographic location, and growth stage of crops. Overall, both indices performed similarly for agricultural impact assessment; however, the MSDI performed better early in the growing season for wheat and barley, indicating high crop production sensitivity to soil moisture deficiency. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is a major fungal disease affecting wheat production worldwide. Since the early 1990s, FHB, caused primarily by Fusarium graminearum, has become one of the most significant diseases faced by wheat producers in Canada and the United States. The increasing FHB problem is likely due to the increased adoption of conservation tillage practices, expansion of maize production, use of susceptible wheat varieties in rotation, and climate variability. Durum wheat (Triticum turgidum sp. durum) is notorious for its extreme susceptibility to FHB and breeding for resistance is complicated because sources of FHB resistance are rare in the primary gene pool of tetraploid wheat. Losses due to this disease include yield, test weight, seed quality, food and feed quality, and when severe, market access. More importantly, it is the contamination with mycotoxins, such as deoxynivalenol, in Fusarium-infected durum kernels that causes the most serious economic as well as food and feed safety concerns. Several studies and thorough reviews have been published on germplasm development and breeding for FHB resistance and the genetics and genomics of FHB resistance in bread or common wheat (71 aestivum): however, similar reviews have not been conducted in durum wheat. Thus, the aim of this review is to summarize and discuss the recent research efforts to mitigate FHB in durum wheat, including quantitative trait locus mapping, genome-wide association studies, genomic prediction, mutagenesis and characterization of genes and pathways involved in FHB resistance. It also highlights future directions, FHB-resistant germplasm, and the potential role of morphological traits to enhance FHB resistance in durum wheat. [ABSTRACT FROM AUTHOR]

• Multi-target inversion technique for simultaneous retrieval of crop biophysical parameters. • Investigated the retrieval approach for RADARSAT-2 SAR data of SMAPVEX-16 campaign. • Biophysical parameters' cross-correlation is well preserved in MTRFR approach. Retrieval of the Plant Area Index (PAI) and wet biomass from polarimetric SAR (PolSAR) data is of paramount importance for in-season monitoring of crop growth. Notably, the joint estimation of biophysical parameters might be effective instead of an individual parameter due to their inherent relationships (possibly nonlinear). The semi-empirical water cloud model (WCM) can be suitably utilized to estimate biophysical parameters from PolSAR data. Nevertheless, instability problems could occur during the model inversion process using traditional inversion approaches. Iterative optimization (IO) can have difficulty in finding the global minima while look up table (LUT) searches have a lower generalization capability. These challenges reduce the transferability of IO and LUT search inversions in computational efficiency and seldom account for the inter-correlation among the parameters. Alternatively, a machine learning regression technique with a regularization routine may provide a stable and optimum solution for ill-posed problems related to the inversion of the WCM. In the present work, the crop biophysical parameters viz. PAI and wet biomass are estimated simultaneously using the multi-target Random Forest Regression (MTRFR) technique. The accuracy of the retrieval method is analyzed using the in-situ measurements and quad-pol RADARSAT-2 data acquired during the SMAPVEX16 campaign over Manitoba, Canada. The inversion process is tested with different polarization combinations of SAR data for wheat and soybean. The validation used ground measured biophysical parameters for various crops, indicating promising results with a correlation coefficient (r) in the range of 0.6–0.8. In addition, the relationship between PAI and wet biomass using the multi-target and single output model is also assessed based on in-situ measurements. The results confirm that the inter-correlation between biophysical parameters is well preserved in the MTRFR based joint inversion technique for both wheat and soybean. [ABSTRACT FROM AUTHOR]

Fusarium graminearum is responsible for production of the mycotoxin deoxynivalenol (DON) on maize and wheat in Ontario, Canada. It has been understood since the early 1980s that in most parts of Canada, the predominant chemotype of F. graminearum is 15ADON, and not the 3ADON chemotype mainly found in Europe and Asia. The discovery of F. graminearum strains that did not produce DON but the structurally related 7-α hydroxy, 15-deacetylcalonectrin (3ANX) and its hydrolysis product 7-α hydroxy, 3,15-dideacetylcalonectrin to (NX) demonstrated that we still have a lot to learn about this well studied but complicated fungus. We conducted a survey of maize and wheat samples from Ontario farms. In the 2015 crop year, we isolated 86 strains and tested a representative subset of 20 using the published genetic probes for assessing genotype. We also developed a targeted LC-MS/MS method for the identification and quantitation of known toxins from this species to determine chemotype. The results showed that 80% of our strains produced some 3ANX in addition to 15ADON and one strain produced 3ANX and no 15ADON. Comparison of chemical data with genotyping revealed that in more than 50% of the cases there was no clear agreement. These data demonstrate the importance of chemical analysis for understanding the toxigenic potential of strains, especially using a LC-MS method that is capable of differentiating 3ADON and 15ADON. For this collection, genotyping of isolates did not produce reliable information on the chemotype. This is the first report of 3ANX toxin production concurrently with 15ADON and suggests that the 3ANX producers in North America likely originated from the 15ADON background. [ABSTRACT FROM AUTHOR]

Genotypes of 290 cultivars from ten countries (four continents) of spring wheat Triticum aestivum , were analyzed through the identification of alleles at the gliadin-encoding (Gli) loci. The group of cultivars bred in one country during the 20th century might be characterized by its level of genetic diversity (H) and a specific set of alleles. Strong differences between genotypes of cultivars bred in different countries were confirmed by cluster analysis of genetic distances. Genotypes of cultivars bred in regions of the same country might differ, but they always composed a single cluster and strongly differed from genotypes from other countries or regions. Therefore, world polymorphism of spring wheat germplasm of the 20th century is highly structured and differentiated between countries and their regions. This differentiation seems to be mainly a result of natural selection acting in different ways in different eco-climatic conditions of breeding and propagation. At a regional scale, statistically significant temporal changes in frequency of some gliadin alleles and a tendency to temporal decrease of overall genetic diversity were discovered in cultivars bred in each of seven regions studied in Australia, Canada and the former USSR. In regions of Canada (provinces of Manitoba and Ontario) and of the former USSR (Saratov), a statistically significant decay of the genetic diversity of cultivars bred during the 20th century was discovered. However, the influence of breeders' selection for end-use wheat quality on the wheat genetic diversity was the least, if any. • Gliadin genotypes of 299 world-wide T. aestivum cultivars and accessions are compared. • Genetic distances between groups of cultivars from different countries are very long. • The 20th-century's wheat polymorphism is highly structured among countries and regions. • There was a statistically confirmed genetic erosion of polymorphism in two regions. • Differentiation of polymorphism is not necessarily a result of breeders' selection for quality. [ABSTRACT FROM AUTHOR]

The impact of climate change on agricultural systems is a major concern as it can have a significant effect on the world food supply. The objective of this study was to evaluate climate change impacts on crop production and nitrate leaching in two distinct climatic zones in Canada. Spring wheat (Triticum aestivum L.) was selected for the semiarid regions of Western Canada (Swift Current, SK) and maize (Zea mays L.) was chosen for the more humid regions of central Canada (Woodslee, ON). Climate scenarios were based upon simulations from a Canadian Regional Climate Model (CanRCM4) under two Representative Concentration Pathways (RCP4.5 and RCP8.5) and crop simulations were conducted using the Decision Support System for Agrotechnology Transfer (DSSAT) model. Compared to the baseline climate scenario, wheat yields increased by 8, 8, 11, 15%, whereas maize yields decreased by 15, 25, 22, 41% under RCP4.5 2050s (2041–2070), RCP4.5 2080s (2071–2100), RCP8.5 2050s and RCP8.5 2080s scenarios, respectively. Annual nitrate leaching increased by 19, 57, 73, 129% at Swift Current and by 84, 117, 208, 317% at Woodslee under the four scenarios, respectively. Adaptation measures suggested that fertilizer N rate for spring wheat should be increased to 80–100 kg N ha-1 to obtain optimal yields although this will result in an additional risk of 5–8 kg N ha-1 nitrate leaching at Swift Current. The fertilizer N rate of 150 kg N ha-1 was found to be suitable for high maize yields at Woodslee. New wheat and maize cultivars with long growing seasons would enable crop growth to match the phenological stage and hence maintain high crop yields to adapt to increased temperatures in the future. [ABSTRACT FROM AUTHOR]

In the 1920s, Canadian farmers created the world's most successful large-scale wheat marketing organization, or wheat "pool." In doing so, they built upon two decades of interprovincial and national cooperative endeavors, providing the pool movement a firm foundation. During the decade, the Canadians spearheaded an effort to bring about a transnational pooling program, especially among wheat producers in the United States, Australia, and the Soviet Union. Representatives from these countries recognized the Canadian pool as the ideal model and worked closely with their counterparts there. As the international wheat pool movement took shape, however, the Great Depression intervened, shattering hopes for the creation of a transnational cooperative network in wheat marketing. [ABSTRACT FROM AUTHOR]

Resumo: In Canada, average grain freight rates are regulated via the Maximum Revenue Entitlement (MRE), while on the US side of the border grain rates are subject to very little oversight. We use this natural experiment to explore how the MRE regulation has impacted freight rates and the distribution of rents in the wheat supply chain since 2012. On both sides of the border, when large crops have exceeded the short‐term capacity of grain export channels to move the crop, export basis has increased and reduced producer prices. In locations not subject to barge competition, US grain freight rates are higher than Canadian rates and are bid up further during periods of congestion. In Canada, MRE regulation redistributes rents away from railways toward grain companies and producers. These higher grain handling margins have increased the incentives to build additional port terminal capacity in the post‐CWB single desk environment. Au Canada, les tarifs marchandises moyens des céréales sont règlementés par le Revenu admissible maximal (RAM), tandis qu'aux États‐Unis, les tarifs céréaliers font l'objet de très peu de suivi. Au moyen de cette expérience naturelle, nous explorons l'impact du RAM sur les tarifs marchandises et sur la distribution des rentes dans la chaine d'approvisionnement du blé depuis 2012. Des deux côtés de la frontière, lorsque de vastes cultures ont excédé la capacité à court terme des voies d'exportation céréalières pour distribuer leurs récoltes, le seuil d'exportation augmente et réduit les prix des producteurs. Là où ils ne sont pas assujettis à la compétition de barges, les tarifs marchandises céréaliers américains s'avèrent plus élevés que les tarifs canadiens et se voient encore surenchéris lors de période de congestion. Au Canada, la règlementation du RAM redirige les rentes des compagnies ferroviaires aux entreprises et producteurs céréaliers. Ces marges de manutention plus élevées ont augmenté les incitatifs pour accroître la capacité des ports‐terminaux dans un environnement à pupitre unique, post Commission canadienne du blé. [ABSTRACT FROM AUTHOR]

The occurrence of P. verrucosum and ochratoxin A (OTA) were surveyed for 3 and 4 years, respectively. A total of 250 samples was collected from an average of 30 farms during the 2011, 2012, 2013 and 2014 winter seasons. Most storage bins surveyed were typically 11 m high round bins made of corrugated, galvanized steel, with flat-bottoms and conical roofs. Samples of clumped grain contained the most P. verrucosum (p<0.05, n = 10) followed by samples taken from the first load (n = 24, mean = 147±87 CFU/g) and last load (n = 17, mean = 101±77 CFU/g). Five grain samples (2.2%) tested positive for OTA, citrinin and OTB at concentrations of 14.7±7.9, 4.9±1.9 and 1.2±0.7 ng/g, with only three samples exceeding 5 ng/g. Grain samples positive for OTA were related to moisture resulting from either condensation or migrating moist warm air in the bin or areas where precipitation including snow entered the bin. Bins containing grain and clumps contaminated with OTA were studied in detail. A number of statistically-significant risk factors for OTA contamination were identified. These included 1) grain clumps accumulated around or directly under manhole openings, 2) debris and residue of old grain or grain clumps collected from the bin walls or left on storage floor and augers and 3) grain clumps accumulated around side doors. Even when grain enters storage below the 14.5% threshold of moisture, condensation and moisture migration occurs in hotspots in modern corrugated steel storage bins. Hot spots of OTA contamination were most often in areas affected by moisture migration due to inadequate aeration and exposure to moisture from precipitation or condensation. Further, we found that the nature of the condensation affects the nature and distribution of small and isolated areas with high incidence of toxin contamination and/or P. verrucosum prevalence in the grain bins examined. [ABSTRACT FROM AUTHOR]

Volunteer summer-annual oilseed rape ( sOSR; Brassica napus) is an ongoing concern in Canadian crop production. Large harvest seed losses and secondary dormancy in this species generate a persistent volunteer seedbank. Yield loss in subsequent crops, potential sOSR oil profile contamination and herbicide-resistance trait introgression create a need for effective sOSR seedbank management. This field study evaluated the effects of timing and type of implement of post-harvest soil disturbance and seeding a winter cereal on volunteer sOSR population persistence and demographic life-stage transition rates at five locations in Manitoba, Canada. Following sOSR harvest and supplemental seed rain, seedbank densities ranged from 6770 to 15360 and 50 to 2610 seeds m−2 among sites in autumn and spring respectively. In contrast to European research on winter-annual oilseed rape, early autumn soil disturbance, shortly after sOSR harvest, was the best strategy to decrease volunteer sOSR persistence (3% population persistence from autumn to spring, compared with 6% in zero tillage). Substantial autumn seedling recruitment (38% of the autumn seedbank) and subsequent winterkill contributed to lower population persistence. Soil disturbance in spring stimulated spring seedling recruitment compared with other disturbance timings (11% and 3% of the spring seedbank, respectively). The implement used for soil disturbance and seeding winter wheat ( Triticum aestivum) had minimal effect on population persistence. This research showed that timing of post-harvest soil disturbance should be utilised as an effective tactic to decrease population persistence of volunteer sOSR via stimulation of autumn seedling recruitment and concomitant winterkill. [ABSTRACT FROM AUTHOR]

Puccinia triticina Eriks., the causal agent of wheat leaf rust, was collected across Canada in 2010 to determine the virulence spectrum present in the pathogen population. From 314 infected leaf collections, 399 single pustule isolates were recovered, including 341 from Manitoba and Saskatchewan, 38 from Ontario, nine from Quebec and 11 from Prince Edward Island (PEI). When analysed for virulence on 16 standard differential lines, 41 different virulence phenotypes were identified. The most common were MLDS (26.1%), TDBJ (22.8%) and TDBG (11.8%). In Manitoba and Saskatchewan, the most common phenotypes were MLDS (29.6%), TDBJ (25.5%) and TDBG (13.8%), which were also abundant in 2009. In Ontario, the most common were MBTN (23.7%), TDBJ (10.5%), MCGJ, MCTN and MLDS (each at 7.9%), whereas in Quebec, each of the nine isolates analysed had a different phenotype. In PEI, the more commonly isolated phenotypes were MBNQ (six isolates), MBTN and MHNQ (two isolates each). Each population had unique virulence phenotypes, and the eastern populations were more diverse than the Manitoba and Saskatchewan population. Virulence trends from previous years continued in 2010, with increasing levels of virulence found for Lr9 and Lr17 while decreasing virulence was found for Lr2a, Lr14a and Lr24. There was no virulence found in 2010 for Lr19, Lr21, Lr22a, Lr29, Lr32 or Lr52. [ABSTRACT FROM AUTHOR]

Background: Mandatory folic acid fortification of white-wheat flour and selected other grain products has reduced the prevalence of neural tube defects in Canada; however, the fortification of whole-wheat flour is not permitted.Objective: The objective of this study was to model the impact of adding folic acid to whole-wheat flour on the folate intake distribution of Canadians.Methods: Twenty-four-hour dietary recall and supplement intake data (n = 35,107) collected in the 2004 Canadian Community Health Survey 2.2 were used to calculate the prevalence of folate inadequacy (POFI) and the proportion of folic acid intakes above the Tolerable Upper Intake Level (UL). In model 1, folic acid was added to whole-wheat flour-containing foods in amounts comparable to those that are mandatory for white-wheat flour-containing foods. In model 2, a 50% overage of folic acid fortification was considered. Models 3 and 4 included assessment of folate intake distributions in adult whole-wheat consumers with or without a fortification overage. SIDE (Software for Intake Distribution Estimation; Department of Statistics and Center for Agricultural and Rural Development, Iowa State University) was used to estimate usual folate intakes.Results: Mean folate intakes increased by ∼ 5% in all sex and age groups when whole-wheat foods were fortified (models 1 and 2; P < 0.0001). Folic acid fortification of whole-wheat flour-containing foods did not change the POFI or percentage of intakes above the UL in the general population, whether in supplement users or nonusers. Among whole-wheat consumers, the POFI was reduced by 10 percentage points after fortification of whole-wheat flour-containing foods (95% CIs did not overlap). The percentage of whole-wheat consumers with intakes above the UL did not change.Conclusion: Although folic acid fortification of whole-wheat flour-containing foods is unlikely to change the POFI or proportion of folic acid intakes above the UL in the general Canadian population, this fortification strategy may reduce the POFI in adult whole-wheat consumers. [ABSTRACT FROM AUTHOR]

Studies were conducted to examine the effects of row spacing and stubble height on surface soil water content, water use, yield, and water use efficiency of canola and wheat in the drier regions of the Canadian prairies. For this purpose, randomized complete block design trials were implemented separately in canola and wheat fields at Central Butte and Swift Current in the Brown soil zone of southwestern Saskatchewan. At each experimental site, two factors and two levels for each factor, i.e., 30- and 60-cm row spacing and 15- and 30-cm stubble heights, were included. Wider row spacing and taller stubble generally increased soil water content for the surface 0–30 cm soil depth, and taller stubble often had greater spatial variability of surface soil water content at both locations. Row spacing or stubble height had minimal effect on water use for both crops at both locations over the two years (2012 and 2013). Yield and water use efficiency of 30-cm row spacing were 1.3–1.6 (Central Butte) and 1.0–1.2 (Swift Current) times greater than those of 60-cm row spacing. Stubble height had little effects on yield and water use efficiency. There were no interactions of row spacing and stubble height on water use, yield, and water use efficiency for either crop. Overall, 30-cm row spacing and 30-cm stubble tended to increase surface soil water content, yield, and water use efficiency for most crop type, year, and site combinations. [ABSTRACT FROM AUTHOR]

While the competitiveness of the Canadian agri-food sector attracted significant research attention since the mid 1980s, no study has measured competitiveness using longitudinal data and determined empirically the drivers of competitiveness. This article contributes to the competitiveness literature by measuring the international competitiveness of wheat, beef, and pork sectors in Canada using data from 1961 to 2011 and by determining the drivers of competitiveness. Our results demonstrate that Canada enjoys competitiveness in the wheat sector but not in the beef or pork sectors. Empirical results also suggest that the competitiveness of the Canadian wheat sector can be enhanced if the cost seed in Canada relative to that in the United States is lower. Similarly, if the relative labor cost of meat processing is lower, the competitiveness of both beef and pork sectors in Canada will be enhanced. Exchange rates are important drivers of international competitiveness of beef and pork sectors in Canada. The decoupled farm policies in Canada do not have a significant impact on the competitiveness of wheat and pork sectors in Canada. While our empirical results seem to indicate that major agri-food policies in Canada may not have delivered the expected benefits, the NRCA index did not allow us to separate the contributions of market and nonmarket failures to competitive performance of Canadian agriculture.Bien que la compétitivité du secteur agroalimentaire canadien ait suscité un vif intérêt de la part des chercheurs depuis le milieu des années 1980, aucune étude ne l'a évaluée à l'aide de données longitudinales et aucune n'en a déterminé de manière empirique les moteurs. Le présent article contribue à la littérature sur la compétitivité en ce sens qu'il présente une évaluation de la compétitivité des secteurs du blé, du bœuf et du porc canadiens sur la scène internationale effectuée à l'aide de données couvrant la période 1961-2011 et en détermine les moteurs. Selon les résultats de notre étude, le Canada jouit d'une compétitivité dans le secteur du blé uniquement. Les résultats empiriques autorisent aussi à penser qu'il serait possible d'accroître la compétitivité du secteur du blé canadien si le coût des semences au Canada était plus faible que celui aux États-Unis. De façon similaire, une baisse du coût relatif de la main-d'œuvre dans les usines de transformation de la viande contribuerait à accroître la compétitivité des secteurs du bœuf et du porc canadiens. Les taux de change sont des moteurs importants de la compétitivité des secteurs du bœuf et du porc canadiens sur la scène internationale. Au Canada, les politiques agricoles découplées n'ont pas de répercussions significatives sur la compétitivité des secteurs du blé et du porc canadiens. Bien que les résultats empiriques de notre étude indiquent que les principales politiques agroalimentaires au Canada n'ont peut-être pas procuré les avantages escomptés, l'indice de l'avantage comparatif révélé normalisé (ACRN) n'a pas permis de distinguer les échecs du marché et ceux de la réglementation quant à la performance de la compétitivité du secteur canadien de l'agriculture. [ABSTRACT FROM AUTHOR]

Prior to 2012, the Canadian Wheat Board (CWB) was a dominant regulatory force in the Canadian grain sector. This paper looks at the historical justifications of the single desk authority of the CWB and reviews previous research examining its performance. In a simulation of price discrimination based on 2013 wheat markets, a possible premium of $7.60/metric tonne is generated assuming a price discriminating CWB. The implications of recent changes in the grain market are discussed, including the increasing area seeded to canola in Canada and the removal of the single desk for the Australian Wheat Board. While the model, as assumed, suggests the CWB's market power was increased by these changes, these gains are reliant on the model assumptions and are modest compared to the recent rise in grain prices and the potential for gains and losses observed in recent export basis variation. Avant 2012, la Commission canadienne du blé (CCB) était une autorité dominante dans le secteur canadien des grains. Dans le présent article, nous examinons les justifications historiques du monopole de la CCB et nous passons en revue les recherches antérieures qui en ont analysé le rendement. D'après une simulation de discrimination par les prix fondée sur les données du marché du blé en 2013, l'hypothèse d'une discrimination par les prix de la part de la CCB engendrerait une prime possible de 7,60 $/tonne métrique. Nous traitons des répercussions des récents changements sur le marché des grains, y compris l'accroissement des superficies consacrées à la culture du canola au Canada et l'abolition du monopole de la Commission australienne du blé (CAB). Bien que le modèle, comme nous l'avions supposé, autorise à penser que les récents changements ont accru le pouvoir de marché de la CCB, ces gains dépendent des hypothèses du modèle et sont modérés comparativement à la hausse récente du prix des grains et au potentiel de gains et de pertes observé dans le récent écart du seuil d'exportation. [ABSTRACT FROM AUTHOR]

Improving technologies and the challenge of producing more bio-products while reducing the environmental footprint of humans are shifting paradigms in agricultural research. Harnessing the microbial resources of arable soils is a new avenue to improve the efficiency of nutrient use in agriculture. The objective of this study was to define how crop management influences the contribution of resident AM fungi to nutrient efficiency and crop productivity. The AM fungal communities of 72 organically and 78 conventionally managed wheat fields of the Canadian prairie were described by 454 pyrosequencing and related to crop productivity and N and P use efficiency. Conventional management reduces soil pH and increases the fluxes of all soil nutrients except S, B, and K. Organic management increased the abundance of Claroideoglomus reads. The efficiency of N and P uptake from soil by organic wheat was 2.3 and 1.8 times higher than that of conventional systems. This high N and P uptake efficiency in organic wheat crops was mainly attributable to the low soil fertility of organic fields, as wheat biomass production was 1.44 times greater in conventional than organic systems. Overall, the amounts of N and P taken up by conventional and organic wheat crops were similar. Plant nutrient balance and the abundance of Paraglomus drove conventional wheat production, whereas organic production depended mainly on soil moisture, plant nutrient balance, and abundance of Glomus, which was associated with reduced and nutrient-inefficient wheat production. The high nutrient concentrations at maturity and the low productivity of organic wheat fit a model of limiting CO2-assimilation. The trade-off between nutrient use efficiency and productivity in low input wheat production could be relieved by reducing the abundance of Glomus species, increasing soil moisture and early N availability, or by improving the inherent CO2 assimilation capacity of wheat. [ABSTRACT FROM AUTHOR]

Grains (common term referring to cereal grains, oilseeds, pulses) are usually harvested at high moisture content and then dried to straight grade (dry) or safe storage moisture levels. Grain drying in freestanding, corrugated galvanized steel or welded steel bins using natural air is the most cost effective drying method with optimum grain quality. Adverse weather conditions and inappropriate fan control strategies may result in poor drying, higher drying cost (electricity and fuel), and grain spoilage. Several traditional fan control (continuous ON, only Day ON, only Night ON) and automated fan control (Natural Air Drying (NAD) and Self- Adapting Variable Heat (SAVH)) strategies were investigated using IntegrisPro model software (OPIsystems Inc.) for their drying potential for wheat using 30 years of historical weather data (1983-2012) from 14 locations in Western Canada (Alberta, Manitoba, and Saskatchewan provinces) which cover nearly 75% of Canada's farming area. Effects of initial wheat moistures (20, 18, and 16%), start dates (August 20th, September 1st, September 15th, and October 1st), locations, airflow rates (0.52, 0.78, and, 1.04 m3min-1t-1) and supplemental heat on drying performance were studied. High moisture wheat (18-20%) can only be dried effectively with sufficient airflow rate (0.78, and, 1.04 m3min-1t-1) and early drying start date (September 15th or earlier). Without automated control, Continuous ON fan control was a better control strategy. The SAVH control strategy gave the optimized results in terms of fan run hours, target moisture, moisture spread, and shrink (over-drying). The Night ON fan control strategy gave the poorest drying results. [ABSTRACT FROM AUTHOR]

Marker-assisted breeding provides an opportunity for wheat breeders to introgress/pyramid genes of interest into breeding lines and to identify genes and/or quantitative trait loci in germplasm to be used as parents. Molecular markers were deployed to assist selection for disease resistance, agronomic and quality traits in several wheat cultivars released for commercial cultivation in Canada. Marker-assisted breeding is routinely used in most wheat breeding programmes for rust resistance (leaf, stem and stripe rust), orange wheat blossom midge resistance, high grain protein concentration, Fusarium head blight and common bunt resistance. Markers are being used selectively within breeding programmes to target traits that relate to market class or regional adaptation. For example, marker-assisted breeding for low lipoxygenase activity and low grain cadmium is being performed in durum breeding programmes and for enhancing stem solidness in programmes targeting resistance to the wheat stem sawfly. Markers are also being utilized for ergot resistance in durum wheat. Increased gluten strength is being selected with a marker for the overexpression of the Bx7 high-molecular-weight glutenin subunit. Marker-assisted breeding is also being used to pyramid resistance genes against a group of stem rust races related to TTKS ( Ug99), a disease that poses a serious threat to global wheat production. Development of tightly linked diagnostic markers and high-throughput genotyping with SNP markers will result in more effective molecular wheat breeding in the near future and will open the door to genomic selection. [ABSTRACT FROM AUTHOR]

• Long-term rotations with/without nitrogen (N) and phosphorus (P) fertilization. • Multiple techniques: P-NMR, P K-edge XANES, P fractionation, phosphatase assays. • Soil pH and organic carbon were significant predictors of soil P forms. • Long-term fertilization altered P forms by changing soil chemistry. • Rotation phase altered total and organic P concentrations regardless of fertilization. Efficient phosphorus (P) management is important for crop production and environmental sustainability of cropping systems. The effects of the agricultural management practices of crop rotation and fertilization on soil P forms and cycling were investigated in plots in Swift Current, SK, Canada, under three crop rotation phases [fallow (F), wheat after fallow (WF), and wheat after wheat (WW)], with four nitrogen (N) and/or P fertilizer treatments (+N+P, -N+P, +N-P, and -N-P), using techniques including sequential fractionation, 31P nuclear magnetic resonance (P-NMR), and P K-edge X-ray absorption near-edge (P-XANES). Soil total P (TP) and organic P (P o) concentrations were significantly reduced in F and WW phases compared to WF regardless of fertilization practice. Compared to WW, WF had the highest grain yield and nutrient uptake. Fertilization with N and P significantly influenced soil total carbon (C), total N, TP, and Mehlich 3-P concentrations and acid phosphatase activities, as well as the concentration of some P pools by sequential fractionation and stable P determined by P-XANES. Stopping P fertilization significantly increased the proportions, but not concentrations, of soil P o determined by P-NMR compared to plots still receiving P fertilizers, while the concentration of total diesters increased in plots fertilized with N. Redundancy analysis showed that soil pH and organic C were the significant predictors of P forms in these soils, suggesting that long-term N and P fertilization altered soil P forms by changing soil chemical properties. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) are being promoted as commercial biofertilizers (bioinoculants) for sustainable agriculture. However, little is known about the survival of AMF inoculants in soil and their impacts on indigenous AMF communities under multiple cropping conditions. A three-year study was conducted at four field-sites across semiarid to subhumid climate zones in the Saskatchewan prairie, Canada. A commercial AMF inoculant containing Rhizophagus irregularis was applied at seeding in the first year of the study in 2011 to the host crop pea (Pisum sativum), grown in open-ended soil cores. The persistence of the inoculant and subsequent phylogenetic changes in the community of the indigenous AMF taxa were assessed for three consecutive cropping seasons (2011–2013), during which wheat (Triticum aestivum) was grown in year two and pea in year three. At harvest of each year, the AMF community was assessed using 18S rRNA gene pyrosequencing of AMF trap roots. A total of 131 AMF OTUs (year 1: 54, year 2: 28, year 3: 49 OTUs, respectively), representing eight genera (Glomus , Funneliformis , Claroideoglomus , Diversispora , Paraglomus , Rhizophagus , Septoglomus , and Archaeospora) was detected. Phylogenetic analysis showed the inoculant could be detected to the end of third cropping season (i.e., 27-month after inoculation) at the Swift Current and Outlook field-sites, but was only detected at the Scott and Melfort field-sites to the end of the first (3-month) and second (15-month) growing seasons, respectively. The commercial inoculant caused alterations (taxa suppression, stimulation, and exclusion) of specific members of the indigenous AMF (abundance and diversity) after the first crop season at Swift Current and after all three seasons at Outlook, Scott, and Melfort sites. Multivariate statistical analysis revealed the survival of the commercial inoculant, and the subsequent changes in the indigenous AMF taxa were dependent on soil environments. [ABSTRACT FROM AUTHOR]

Some fungal species have been shown to improve plant growth under drought conditions and to increase plant phosphorus ( P) uptake from the soil. How moisture limitation, P availability and fungal inoculation interact to affect plant physiology and growth is, however, poorly understood. Here, we studied the combined effects of fungal (arbuscular mycorrhizal fungi ( AMF) or Penicillium spp.) inoculations and phosphorus ( P) fertilization (0, 45 and 90 kg ha−1) on the net rate of photosynthesis, water-use efficiency, P uptake and growth of spring wheat ( Triticum aestivum var. Superb) under field conditions at two locations ( Castor and Vegreville) in Alberta, Canada. Both fungal inoculation and P application increased the rate of photosynthesis. Under the same P level, AMF inoculation had a greater positive effect on the rate of photosynthesis than Penicillium inoculation. The AMF inoculation increased the instantaneous water-use efficiency ( WUEi) of plants at Castor, but not at Vegreville. Leaf carbon isotope discrimination ( CID, Δ13 C) increased with the rate of P application but was not affected by fungal inoculations. Phosphorus concentrations of stem and seed increased with both fungal inoculation and P application irrespective of location, with AMF inoculation showing the largest effects. The interaction between P addition and fungal inoculation was significant for stem P concentration in Vegreville. Both fungal inoculation and P application increased the leaf area index ( LAI), biomass production and grain yield at both locations. Under the same P level, AMF inoculation had a greater positive effect on LAI, biomass production and grain yields than Penicillium inoculation. Morphological characters such as spike length and kernels/spike were also improved by fungal inoculation and P application at both locations. We conclude that the studied sites were deficient in P availability, and both fungal inoculation and P application improved P uptake and crop productivity, while the effect of fungal inoculation on water-use efficiency was site specific. [ABSTRACT FROM AUTHOR]