Studies are being conducted to develop strategies to reduce the adverse effects of salinity stress. In the present study, it was aimed to determine the interactive effects of salinity stress with biochar on plant growth-the physiological and biochemical attributes of forage peas (Pisum sativum ssp. arvense L.). Salt applications were carried out with irrigation water at concentrations of 0, 25, 50, 75, and 100 mM NaCl. The experiment was conducted using a randomized complete block design with three applications [control: 0 (B0), 2.5% biochar (B1), and 5% biochar (B2)], five salt doses [0 (S0), 25 (S1), 50 (S2), 75 (S3), and 100 (S4) mM NaCl], and three replications, arranged in a 3 × 5 factorial arrangement. In the salt-stressed environment, the highest plant height (18.75 cm) and stem diameter (1.71 mm) in forage pea seedlings were obtained with the application of B1. The root fresh (0.59 g/plant) and dry weight (0.36 g/plant) were determined to be the highest in the B1 application, both in non-saline and saline environments. A decrease in plant chlorophyll content in forage pea plants was observed parallel to the increasing salt levels. Specifically, lower H2O2, MDA, and proline content were determined at all salt levels with biochar applications, while in the B0 application these values were recorded at the highest levels. Furthermore, in the study, it was observed that the CAT, POD, and SOD enzyme activities were at their lowest levels at all salt levels with the biochar application, while in the B0 application, these values were determined to be at the highest levels. There was a significant decrease in plant mineral content, excluding Cl and Na, parallel to the increasing salt levels. The findings of the study indicate that biochar amendment can enhance forage peas\' growth by modulating the plant physiology and biochemistry under salt stress. Considering the plant growth parameters, no significant difference was detected between 2.5% and 5% biochar application. Therefore, application of 2.5 biochar may be recommended.

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a highly destructive polyphagous pest that primarily damages maize. Maize is considered a most versatile crop for growing intercrops due to the wide row it needs. Maize-pea intercropping is preferred by small and marginal farmers worldwide due to various advantages including higher yield and improved economic benefits. However, the success of this intercropping system may be hampered if pea could sustain the FAW population. Thus, to clarify the fitness and potential effect of S. frugiperda on pea, we analysed the survival and development of S. frugiperda fed on pea leaves in the laboratory and constructed age-stage and two-sex life tables. Results showed that FAW successfully completed its life cycle when fed on pea and produced fertile offspring. The pre-adult duration was significantly higher on pea than maize. The net reproductive rate, intrinsic and finite rate of population increase on pea (135.06 offspring per individual, 0.12 offspring per individual per day and 1.13 times per day) were all significantly different from those on maize (417.64 offspring per individual, 0.19 offspring per individual per day and 1.21 times per day). The probability of survival of S. frugiperda at each stage was lower when fed on pea leaves than that of maize-fed larvae. Due to the overlapping growth periods of the maize and pea, S. frugiperda can easily proliferate throughout the year by shifting between adjacent crops. Thus, this study revealed the adaptability of S. frugiperda for pea and provides the foundation for further assessment of FAW risk to other inter-crops.

Bean leafroll virus (BLRV; Bean leafroll virus), a single-stranded RNA virus in the genus Luteovirus, is phloem-limited and primarily transmitted by aphids in a non-propagative, persistent manner (Rashed et al., 2018; Kidanemariam and Abraham, 2023). BLRV infects various legumes and has been reported from major pulse-growing regions worldwide (Agindotan et al., 2019) but not in the Canadian Prairies. Its impact on crop yield varies with plant and virus genotypes and the timing of infection. Some pea fields have experienced disease rates of up to 80% (Clement et al., 2020; Hampton, 1983). Throughout the 2022 growing season (June and July), pulse fields from across Saskatchewan were randomly selected and surveyed, and symptomatic plants demonstrating leaf yellowing and chlorosis were collected and stored at -80°C before processing. Observed symptoms included necrotic spots, chlorosis, leaf mottling, leaf rolling in peas, severe bright yellowing, and leaf marginal necrosis in chickpeas. BLRV detection was performed on 35 leaves of the collected samples using both Enzyme-Linked Immunosorbent Assay (ELISA) and Reverse transcription polymerase chain reaction (RT-PCR). ELISA testing followed the manufacturer\'s protocol using a commercial kit (Nano Diagnostics, San Jose, CA, USA). Total RNAs were extracted from the frozen samples using TRIzol (Invitrogen, Carlsbad, CA, USA). For the detection of the diverse BLRV isolates, sequences of various isolates were aligned and primers were specifically designed in-house, targeting the virus\'s highly conserved regions on the GP3 and 3\' UTR (see Supplementary material). Additional primers were also designed targeting coat protein (CP) coding regions which were previously used for BLRV detection (Agindotan et al. 2019; Larsen & Webster 1999). PCR testing of 35 symptomatic samples including 12 pea plants and 23 chickpea plants, identified the presence of BLRV in two symptomatic samples, one each from a field pea (Pisum sativum L. var. CDC Inca) and a desi-type chickpea (Cicer arietinum L. var. CDC Leader). The infected pea and chickpea samples were found in Saskatoon, SK (Coordinates: 52°9\'27\'\'N,106°34\'14\"W), and the Leader area, southwest of Saskatchewan, SK (Coordinates: 50°52\'14\"N,109°23\'11\"W), respectively. PCR amplicons were purified and sent for Sanger sequencing. The reads were assembled to generate 1666 and 323 nucleotides from pea and chickpea, respectively, with a minimum of 2X coverage. Partial nucleotide sequences of the BLRV isolates obtained from pea (PsSK1) and chickpea (CaSK1) (GenBank accession numbers: PP240429, PP266588) showed (1521/1574 bp) 96.63% and (316/323 bp) 97.83% similarity with a BLRV reference isolate sequence (NC_003369) and to an isolate from Argentina (KR261610) which was reported on Medicago sativa L. with (1555/1574 bp) 98.79% and (319/323 bp) 98.76% similarity, correspondingly. Both infected samples were confirmed to be BLRV-infected through the ELISA and exhibited a high interaction ratio (PsSK1: 0.319 and CsSK1: 0.245) compared to a positive control (0.292) after 30 minutes as measured at 450 nm. This is the first report of BLRV in the pulse-growing region of the Canadian Prairies. In Saskatchewan, there is no history of BLRV despite the large amount of area growing susceptible crops. Therefore, the survey project that this study was part of was not intended to evaluate the severity of BLRV but rather to determine if there is any virus present that might have been overlooked. The samples were therefore taken randomly, with a focus on the number of fields and geographic coverage rather than focusing on multiple plants per field. Moreover, fields were not chosen based on symptoms but rather at random. Although, plants within fields were chosen because they displayed symptoms. Typically, a disease note includes estimates of severity and potential risk; however, that is not possible for this study. Rather, the fact that it was detected indicates a greater risk than previously perceived, since it was assumed that BLRV was not present. These findings highlight the need for further research on the virus\'s current status, its impact on crop production, and the resistance of pulse varieties grown in Saskatchewan.

Rhizobial attachment to host legume roots is the first physical interaction of bacteria and plants in symbiotic nitrogen fixation. The pH-dependent primary attachment of Rhizobium leguminosarum biovar viciae 3841 to Pisum sativum (pea) roots was investigated by genome-wide insertion sequencing, luminescence-based attachment assays, and proteomic analysis. Under acid, neutral, or alkaline pH, a total of 115 genes are needed for primary attachment under one or more environmental pH, with 22 genes required for all. These include components of cell surfaces and membranes, together with enzymes that construct and modify them. Mechanisms of dealing with stress also play a part; however, exact requirements vary depending on environmental pH. RNASeq showed that knocking out the two transcriptional regulators required for attachment causes massive changes in the bacterial cell surface. Approximately half of the 54 proteins required for attachment at pH 7.0 have a role in the later stages of nodule formation. We found no evidence for a single rhicadhesin responsible for alkaline attachment, although sonicated cell surface fractions inhibited root attachment at alkaline pH. Our results demonstrate the complexity of primary root attachment and illustrate the diversity of mechanisms involved.
OBJECTIVE: The first step by which bacteria interact with plant roots is by attachment. In this study, we use a combination of insertion sequencing and biochemical analysis to determine how bacteria attach to pea roots and how this is influenced by pH. We identify several key adhesins, which are molecules that enable bacteria to stick to roots. This includes a novel filamentous hemagglutinin which is needed at all pHs for attachment. Overall, 115 proteins are required for attachment at one or more pHs.

The present study investigated the effects of low protein diets with different starch sources and starch to protein ratio on growth, digestibility, intestinal health, caecal short chain fatty acids (SCFAs), serum cholesterol and triglycerides in broiler chickens. Eight hundred one-day-old male broiler chicks (Ross 308) were randomly allotted to one of 4 dietary treatments with 10 repeats and 20 birds in each repeat. The dietary treatments included 1) a standard protein corn-SBM based diet (SP), 2) a low protein corn-SBM based diet (LPI) without reduced starch: protein ratio, 3) a low protein corn-SBM based diet (LPII) with reduced starch: protein ratio, and 4) a low protein corn-SBM-peas based diet (LPP) and reduced starch: protein ratio. Soy hulls were added in the LPII and LPP diets to reduce starch: protein ratio. During the experiment period from 11 to 24 d, FI was not affected by the dietary treatments (P > 0.05). The BWG was significantly reduced in the LPI diet compared to the SP diet (P < 0.05). Likewise, FCR deteriorated in LPI and LPII but was better in the SP diet followed by the LPP diet (P < 0.05). The apparent total tract digestibility (ATTD) of dry matter (DM) varied significantly among the dietary treatments (P < 0.01). While ATTD of starch was similar for all the diets except the LPP diet wherein the ATTD of starch was significantly lower (P < 0.001). Ether extract digestibility was also significantly different between the SP and LPII dietary treatments (P < 0.01). The AME and AMEn values were significantly lower in the LPP diet compared with other dietary treatments (P < 0.001). Nitrogen retention (%) was increased in all the LP diets compared with the SP diet (P < 0.001), but it was significantly better in both LPII and LPP diets compared to the LPI diet. The data showed that cecal SCFAs production was increased in the LPII and LPP compared to the SP and LPI diets (P < 0.001). Further, the production of acetic, butyric, and propionic acids was substantially higher in the LPP diet (P < 0.001). There was no significant difference in gene expression of Claudin-1 and ZO-1 (P > 0.05). However, MUC-2 and GLUT-1 gene expression were significantly downregulated in the LPI diet (P < 0.05). The concentration of cholesterol and triglycerides was significantly increased in the LPI diet (P < 0.001). In conclusion, the addition of peas as a slowly digestible starch source combined with soy hulls in low protein diet helped to partly recover the growth performance and improved cecal SCFAs production compared to other low protein diets with and without reduced starch: protein ratio in broiler chickens.

Biological nitrogen fixation in legume plants depends on the diversity of rhizobia present in the soil. Rhizobial strains exhibit specificity towards host plants and vary in their capacity to fix nitrogen. The increasing interest in rhizobia diversity has prompted studies of their phylogenetic relations. Molecular identification of Rhizobium is quite complex, requiring multiple gene markers to be analysed to distinguish strains at the species level or to predict their host plant. In this research, 50 rhizobia isolates were obtained from the root nodules of five different Pisum sativum L. genotypes (\"Bagoo\", \"Respect\", \"Astronaute\", \"Lina DS\", and \"Egle DS\"). All genotypes were growing in the same field, where ecological farming practices were applied, and no commercial rhizobia inoculants were used. The influence of rhizobial isolates on pea root nodulation and dry biomass accumulation was determined. 16S rRNA gene, two housekeeping genes recA and atpD, and symbiotic gene nodC were analysed to characterize rhizobia population. The phylogenetic analysis of 16S rRNA gene sequences showed that 46 isolates were linked to Rhizobium leguminosarum; species complex 1 isolate was identified as Rhizobium nepotum, and the remaining 3 isolates belonged to Rahnella spp., Paenarthrobacter spp., and Peribacillus spp. genera. RecA and atpD gene analysis showed that the 46 isolates identified as R. leguminosarum clustered into three genospecies groups (B), (E) and (K). Isolates that had the highest influence on plant dry biomass accumulation clustered into the (B) group. NodC gene phylogenetic analysis clustered 46 R. leguminosarum isolates into 10 groups, and all isolates were assigned to the R. leguminosarum sv. viciae.

Prolonged drought conditions are a critical challenge for agricultural advancement, threatening food security and environmental equilibrium. To overcome these issues, enhancing plant resilience to drought is essential for plant growth and sustainable agriculture. In this study, blue-emitting antioxidant carbon dots (B-CDs), synthesized from citric acid and ascorbic acid, emerged as a promising solution to enhance the drought resistance of peas (Pisum sativum L.). B-CDs can efficiently scavenge reactive oxygen species (ROS), which are harmful in excess to plants under stress conditions. Through detailed experimental analyses and density functional theory (DFT) studies, it is found that these B-CDs possess structures featuring eight-membered aromatic rings with abundant oxygen-containing functional groups, providing active sites for reactions with ROS. The practical benefits of the B-CDs are evident in tests with pea plants exposed to drought conditions. These plants show a remarkable reduction in ROS accumulation, an increase in photosynthetic efficiency due to improved electron transfer rates, and significant growth enhancement. Compared to untreated controls under drought stress, the application of B-CDs results in an impressive increase in the fresh and dry weights of both the shoots and roots of pea seedlings by 39.5 and 43.2% for fresh weights and 121.0 and 73.7% for dry weights, respectively. This suggests that B-CDs can significantly mitigate the negative effects of drought on plants. Thus, leveraging B-CDs opens a novel avenue for enhancing plant resilience to abiotic stressors through nanotechnology, thereby offering a sustainable pathway to counter the challenges of drought in agriculture.

BACKGROUND: Protein influences acute postprandial glucose and insulin responses, but the effects of dose, protein type, and health status are unknown.
OBJECTIVE: We aimed to determine the acute effect of adding protein to carbohydrate on postprandial responses and identify effect modifiers.
METHODS: We searched MEDLINE, EMBASE, and Cochrane databases through 30 July, 2023 for acute, crossover trials comparing acute postprandial responses elicited by carbohydrate-containing test meals with and without added protein in adults without diabetes or with type 2 (T2DM) or type 1 (T1DM) diabetes mellitus. Group data were pooled separately using generic inverse variance with random-effects models and expressed as the ratio of means with 95% confidence interval. Risk of bias and certainty of evidence (Grading of Recommendations Assessment, Development, and Evaluation) were assessed.
RESULTS: In 154 trial comparisons of animal, dairy, and plant proteins (without diabetes, n = 22, 67, 32, respectively; T2DM, n = 14, 16, 3, respectively), each gram protein per gram available carbohydrate (g/g) reduced the glucose area under the curve (AUC) less in adults with T2DM than in those without diabetes (-10% compared with -50%, P < 0.05) but increased the insulin AUC similarly (+76% compared with +56%). In subjects without diabetes, each g/g of dairy and plant protein reduced glucose AUC by 52% and 55%, respectively, and increased the insulin AUC by 64% and 45%, respectively (all P < 0.05). Animal proteins significantly reduced the glucose AUC by 31% and increased the insulin AUC by 37% (pooled effects) but without a significant dose-response. In adults with T2DM, animal protein reduced the glucose AUC by 13% and increased the insulin AUC by 105%, with no significant dose-response. Dairy protein reduced the glucose AUC by 18% (no dose-response), but each g/g increased the insulin AUC by 34% (P < 0.05). In adults with T1DM, protein increased the glucose AUC by 40% (P < 0.05, n = 5). Data source (reported AUC compared with calculated AUC) and study methodology quality significantly modified some outcomes and contributed to high between-study heterogeneity.
CONCLUSIONS: In people without diabetes, adding dairy or plant protein to a carbohydrate-containing meal elicits physiologically significant reductions in glucose AUC and increases insulin AUC. Animal protein may slightly reduce the glucose AUC and may increase the insulin AUC. In people with T2DM, protein may not have such large and consistent effects. Further research is needed to determine if the effects of protein differ by health status and protein source. This study was registered at PROSPERO as CRD42022322090.

BACKGROUND: Effective population size (Ne) is a pivotal parameter in population genetics as it can provide information on the rate of inbreeding and the contemporary status of genetic diversity in breeding populations. The population with smaller Ne can lead to faster inbreeding, with little potential for genetic gain making selections ineffective. The importance of Ne has become increasingly recognized in plant breeding, which can help breeders monitor and enhance the genetic variability or redesign their selection protocols. Here, we present the first Ne estimates based on linkage disequilibrium (LD) in the pea genome.
RESULTS: We calculated and compared Ne using SNP markers from North Dakota State University (NDSU) modern breeding lines and United States Department of Agriculture (USDA) diversity panel. The extent of LD was highly variable not only between populations but also among different regions and chromosomes of the genome. Overall, NDSU had a higher and longer-range LD than the USDA that could extend up to 500 Kb, with a genome-wide average r2 of 0.57 (vs 0.34), likely due to its lower recombination rates and the selection background. The estimated Ne for the USDA was nearly three-fold higher (Ne = 174) than NDSU (Ne = 64), which can be confounded by a high degree of population structure due to the selfing nature of pea.
CONCLUSIONS: Our results provided insights into the genetic diversity of the germplasm studied, which can guide plant breeders to actively monitor Ne in successive cycles of breeding to sustain viability of the breeding efforts in the long term.

To learn more about the nutritional composition and health benefits for human consumers of peas, we used a widely targeted metabolomics-based approach to reveal the metabolite components from three main varieties, and a total of 1095 metabolites were identified. A comparison of 487 differentially accumulated metabolites shared among three varieties of fresh and dried peas found most of the amino acids and derivatives were downregulated and most of the lipids and flavonoids were upregulated in dried peas. Furthermore, comparing the main nutrient profiles exclusively showed that there were few differences in free fatty acids, sugars, vitamins, and alkaloids between dried and fresh peas. Peas are especially enriched with B-group vitamins. Through detailed identification and classification, the flavonoid pathway of peas was revealed; a variety of glycosylated derivatives from kaempferol, quercetin, and luteolin were confirmed to be abundant in peas. It was also found that isoflavones are richer in peas than in many other plants, and putatively the isoflavone synthesis pathway originates from liquiritigenin and naringenin. Our study not only offers guidance for understanding the nutritional components of peas, but also provides the basis for healthy diet analysis of the edible value and health benefits of peas.