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Soil salinity is one of the major environmental constraints that limits crop yield and nearly 7% of the total area worldwide is affected by salinity. Salinity-induced oxidative stress causes membrane damage during germination and seedling growth. Indian mustard is a major oilseed crop in India and its production and productivity are severely affected by salt stress. Breeding Brassica cultivars for salinity tolerance by conventional means is very difficult and time-consuming. Therefore, understanding the molecular components associated with salt tolerance is needed to facilitate breeding for salt tolerance in Brassica. In this investigation, quantitative trait loci (QTLs) associated with salt tolerance were identified using F2:3 mapping population developed from a cross between CS52 (salinity tolerant) and RH30 (salinity sensitive). Parents and F2:3 were evaluated under controlled and salinity stress conditions for 14 morpho-physiological traits for two consecutive generations (F2 and F2:3), explaining proportion of the phenotypic variance under control condition. Simple sequence repeat (SSR) markers were used for mapping studies. A genetic linkage map based on 42 simple sequence repeats (SSRs) markers was constructed covering 2298.5 ​cM (Haldane) to identify the loci associated with salt tolerance in Brassica juncea. Forty-one SSRs showing polymorphism in the parents (CS52 and RH30) were mapped on 8 linkage groups (C1–C8). One marker (nga 129) did not map to any of the linkage group and was excluded from mapping. Linkage group 5 (C5; 317.9 ​cM) was longest and linkage group 1 (C1, 255.0 ​cM) was shortest. Further, we identified 15 QTLs controlling 8 traits using F2:3 population. These QTLs explained 12.44–60.63% of the phenotypic variation with a LOD score range of 3.62–5.97. Out of these QTLs, QMI4.1 related to membrane injury showed 51.28% phenotypic variance with a LOD score of 3.34. QTL QBYP8.1 related to biological yield per plant showed 60.63% phenotypic variance at a LOD score of 3.62. The highest LOD score of 5.97 was recorded for QTL related to seed yield per plant (QSYP4.1). Major QTLs were QTL for biological yield per plant (QBYP8.1), QTL for siliquae per plant (QSP4.1), QTL for primary branches (QPB4.1), QTLs for seed per siliqua (QSS4.1, QSS4.2), QTL for seed yield per plant (QSYP4.1), and QTL for membrane injury (QMI8.1) which showed more than 50% phenotypic variance. These QTLs identified in our study need to be confirmed in other populations as well so that these can be used in marker-assisted selection and breeding to enhance salt tolerance in Brassica juncea.

The atypical IκB family member Bcl3 associates with p50/NF-κB1 or p52/NF-κB2 homodimers in the nucleus, and positively or negatively modulates transcription in a context-dependent manner. In mice lacking Bcl3 globally or specifically in CD11c+ cells, we previously reported that Toxoplasma gondii infection is uniformly fatal and is associated with an impaired Th1 immune response. Since Bcl3 expression in dendritic cells (DC) is pivotal for antigen presentation and since classical DCs (cDC) are major antigen presenting cells, we investigated the role of Bcl3 specifically in cDCs in vivo by crossing Zbtb46 cre mice with Bcl3flx/flx mice. Bcl3flx/flx Zbtb46 cre mice were as susceptible to lethal T. gondii infection as total Bcl3-/- mice and generated poor Th1 immune responses. Consistent with this, compared to wildtype controls, splenic Xcr1+ Bcl3-deficient cDC1 cells were defective in presenting Ova antigen to OT-I cells both for Ova257-264 peptide and after infection with Ovalbumin-expressing T. gondii. Moreover, splenic CD4+ and CD8+ T cells from infected Bcl3flx/flx Zbtb46 cre mice exhibited decreased T. gondii-specific priming as revealed by both reduced cytokine production and reduced T. gondii-specific tetramer staining. In vitro differentiation of cDCs from bone marrow progenitors also revealed Bcl3-dependent cDC-specific antigen-presentation activity. Consistent with this, splenocyte single cell RNA seq (scRNAseq) in infected mice revealed Bcl3-dependent expression of genes involved in antigen processing in cDCs. We also identified by scRNAseq, a unique Bcl3-dependent hybrid subpopulation of Zbtb46+ DCs co-expressing the monocyte/macrophage transcription factor Lysozyme M. This subpopulation exhibited Bcl3-dependent expansion after infection. Likewise, by flow cytometry we identified two T. gondii-induced hybrid subpopulations of Bcl3-dependent cDC1 and cDC2 cells both expressing monocyte/macrophage markers, designated as icDC1 and icDC2. Together, our results indicate that Bcl3 in classical DCs is a major determinant of protective T cell responses and survival in T. gondii-infection.

Cluster bean popularly known as “guar” is a drought-tolerant, annual legume that has recently emerged as an economically important crop, owing to its high protein and gum content. The guar gum has wide range of applications in food, pharma, and mining industries. India is the leading exporter of various cluster bean-based products all across the globe. Non-coding RNAs (miRNAs) are involved in regulating the expression of the target genes leading to variations in the associated pathways or final protein concentrations. The understanding of miRNAs and their associated targets in cluster bean is yet to be used to its full potential. In the present study, cluster bean EST (Expressed Sequence Tags) database was exploited to identify the miRNA and their predicted targets associated with metabolic and biological processes especially response to diverse biotic and abiotic stimuli using in silico approach. Computational analysis based on cluster bean ESTs led to the identification of 57 miRNAs along with their targets. To the best of our knowledge, this is the first report on identification of miRNAs and their targets using ESTs in cluster bean. The miRNA related to gum metabolism was also identified. Most abundant miRNA families predicted in our study were miR156, miR172, and miR2606. The length of most of the mature miRNAs was found to be 21nt long and the range of minimal folding energy (MFE) was 5.8–177.3 (−kcal/mol) with an average value of 25.4 (−kcal/mol). The identification of cluster bean miRNAs and their targets is predicted to hasten the miRNA discovery, resulting in better knowledge of the role of miRNAs in cluster bean development, physiology, and stress responses.

This study showcases the development of a genosensor utilizing a nanoscale NiO thin film. The genosensor is constructed on a glass substrate coated with tin-doped indium oxide (ITO) and is designed for the specific detection of DNA sequences associated with Puccinia striiformis f. sp. tritici (Pst), the causal agent of wheat yellow rust. The detection process relies on the utilization of methylene blue (MB) as an electrochemical indicator, with NiO acting as the matrix and the electrochemical measurement system serving as the transducer. Various single-stranded DNA oligonucleotide sequences related to Pst pathogenesis are employed as probes to enable sensing. The electrochemical response of the nanoscale bioelectrode is characterized and studied using two distinct electrochemical techniques, cyclic voltammetry (CV) and differential pulse voltammetry (DPV), in conjunction with a potentiostat. The detection ranges spans from 40 pg μ l ^−1 to 115 ng μ l ^−1 , demonstrating a linear correlation with exceptional precision. The absence of DNA-based biosensors for the detection of Puccinia striiformis f. sp. tritici (Pst) has prompted the need for a new method to address the limitations associated with previously reported technologies. Although surface plasmon resonance (SPR) immunoassays have been reported for Pst detection, the development of DNA-based biosensors specifically tailored for Pst detection remains unexplored. Introducing a novel method aims to overcome the challenges and shortcomings of existing techniques, providing a new approach to detect and combat the devastating effects of Pst on wheat crops. By leveraging the advantages of DNA-based biosensors, such as their sensitive and precise detection capabilities, this new method seeks to enhance the accuracy and efficiency of Pst detection, ultimately contributing to the development of effective strategies for disease management and crop protection. The developed nanoscale electrochemical DNA sensor offers outstanding sensitivity, extended shelf life, and reliable recovery, effectively minimizing the likelihood of obtaining erroneous results. A significant highlight of this study is the first-time utilization of conserved sequences associated with pathogenesis in selected Pst strains for the development of a nanoscale genosensor.

Phytophthora species cause crop losses and reduce the quality of greenhouse and nursery plants. Phytophthora species can also be moved long distances by the plant trade, potentially spreading diseases to new hosts and habitats. Phytosanitary approaches based on quarantines and endpoint inspections have reduced, but not eliminated, the spread of Phytophthora species from nurseries. It is therefore important for plant production facilities to identify potential sources of contamination and to take corrective measures to prevent disease. We applied a systems approach to identify sources of contamination in three container nurseries in Oregon, California, and South Carolina. Surface water sources and recaptured runoff water were contaminated with plant pathogenic species at all three nurseries, but one nursery implemented an effective disinfestation treatment for recycled irrigation water. Other sources of contamination included cull piles and compost that were incorporated into potting media, infested soil and gravel beds, used containers, and plant returns. Management recommendations include preventing contact between containers and contaminated ground, improving drainage, pasteurizing potting media ingredients, steaming used containers, and quarantine and testing of incoming plants for Phytophthora species. These case studies illustrate how recycled irrigation water can contribute to the spread of waterborne pathogens and highlight the need to implement nursery management practices to reduce disease risk.

Recycling of irrigation water increases disease risks due to spread of waterborne oomycete plant pathogens such as Phytophthora, Pythium, and Phytopythium. A comprehensive metabarcoding study was conducted to determine spatial and temporal dynamics of oomycete communities present in irrigation water collected from a creek (main water source), a pond, retention reservoirs, a chlorinated water reservoir, and runoff channels within a commercial container nursery in Oregon over the course of 1 year. Two methods, filtration and leaf baiting, were compared for the detection of oomycete communities. Oomycete communities in recycled irrigation water were less diverse but highly enriched with biologically active plant pathogens as compared with the creek water. The filtration method captured a larger portion of oomycete diversity, while leaf baiting was more selective for plant-associated oomycete species of Phytophthora and a few Pythium and Phytopythium species. Seasonality strongly influenced oomycete diversity in irrigation water and detection with leaf baiting. Phytophthora was the major colonizer of leaf baits in winter, while all three genera were equally abundant on leaf baits in summer. The metabarcoding approach was highly effective in studying oomycete ecology, however, it failed to distinguish some closely related species. We developed a custom oomycete internal transcribed spacer (ITS)1 reference database containing shorter sequences flanked by ITS6 and ITS7 primers used in metabarcoding and used it to assemble a list of indistinguishable species complexes and clusters to improve identification. The predominant bait-colonizing species detected in recycled irrigation water were the Phytophthora citricola-complex, Phytophthora syringae, Phytophthora parsiana-cluster, Phytophthora chlamydospora, Phytophthora gonapodyides, Phytophthora irrigata, Phytophthora taxon Oaksoil-cluster, Phytophthora citrophthora-cluster, Phytophthora megasperma-cluster, Pythium chondricola-complex, Pythium dissotocum-cluster, and Phytopythium litorale.

Indian mustard (Brassica juncea (L.) Czern & Coss) is the major oilseed crop of India ranking first both in acreage and production of rapeseed and mustard in Asia. Among abiotic stresses, drought condition may cause the most fatal economic losses in agriculture due to their wide range occurrence. Present investigation was undertaken with the objective to study RB 50 × Kranti F2:3 population under irrigated and drought environments for phenotypic and genetic variability, broad-sense heritability, and interrelationships among agronomic and seed quality traits to select Indian mustard genotypes for drought tolerance in research area of oilseed section. The study was carried out at CCS Haryana Agricultural University, Hisar during rabi 2014-15. Higher mean values for agronomic traits were observed under irrigated than drought environment. Phenotypic correlation coefficient analysis of F2:3 populations under irrigated conditions was calculated to assess the association between various traits. Fifty three promising plants with higher seed yield as well as better physiological traits having greater drought tolerance were selected, which may be useful material for further studies and cultivar development for drought tolerance.

Resistance genes are an effective means for disease control in plants. They predominantly function by inducing a hypersensitive reaction, which results in localized cell death restricting pathogen spread. Some resistance genes elicit an atypical response, termed extreme resistance, where resistance is not associated with a hypersensitive reaction and its standard defense responses. Unlike hypersensitive reaction, the molecular regulatory mechanism(s) underlying extreme resistance is largely unexplored. One of the few known, naturally occurring, instances of extreme resistance is resistance derived from the soybean Rsv3 gene, which confers resistance against the most virulent Soybean mosaic virus strains. To discern the regulatory mechanism underlying Rsv3-mediated extreme resistance, we generated a gene regulatory network using transcriptomic data from time course comparisons of Soybean mosaic virus-G7-inoculated resistant (L29, Rsv3-genotype) and susceptible (Williams82, rsv3-genotype) soybean cultivars. Our results show Rsv3 begins mounting a defense by 6 hpi via a complex phytohormone network, where abscisic acid, cytokinin, jasmonic acid, and salicylic acid pathways are suppressed. We identified putative regulatory interactions between transcription factors and genes in phytohormone regulatory pathways, which is consistent with the demonstrated involvement of these pathways in Rsv3-mediated resistance. One such transcription factor identified as a putative transcriptional regulator was MYC2 encoded by Glyma.07G051500. Known as a master regulator of abscisic acid and jasmonic acid signaling, MYC2 specifically recognizes the G-box motif ("CACGTG"), which was significantly enriched in our data among differentially expressed genes implicated in abscisic acid- and jasmonic acid-related activities. This suggests an important role for Glyma.07G051500 in abscisic acid- and jasmonic acid-derived defense signaling in Rsv3. Resultantly, the findings from our network offer insights into genes and biological pathways underlying the molecular defense mechanism of Rsv3-mediated extreme resistance against Soybean mosaic virus. The computational pipeline used to reconstruct the gene regulatory network in this study is freely available at https://github.com/LiLabAtVT/rsv3-network.

Two low-phytate soybean (Glycine max (L.) Merr.) mutant lines- V99-5089 (mips mutation on chromosome 11) and CX-1834 (mrp-l and mrp-n mutations on chromosomes 19 and 3, respectively) have proven to be valuable resources for breeding of low-phytate, high-sucrose, and low-raffinosaccharide soybeans, traits that are highly desirable from a nutritional and environmental standpoint. A recombinant inbred population derived from the cross CX1834 x V99-5089 provides an opportunity to study the effect of different combinations of these three mutations on soybean phytate and oligosaccharides levels. Of the 173 recombinant inbred lines tested, 163 lines were homozygous for various combinations of MIPS and two MRP loci alleles. These individuals were grouped into eight genotypic classes based on the combination of SNP alleles at the three mutant loci. The two genotypic classes that were homozygous mrp-l/mrp-n and either homozygous wild-type or mutant at the mips locus (MIPS/mrp-l/mrp-n or mips/mrp-l/mrp-n) displayed relatively similar ~55% reductions in seed phytate, 6.94 mg g -1 and 6.70 mg g-1 respectively, as compared with 15.2 mg g-1 in the wild-type MIPS/MRP-L/MRP-N seed. Therefore, in the presence of the double mutant mrp-l/mrp-n, the mips mutation did not cause a substantially greater decrease in seed phytate level. However, the nutritionally-desirable high-sucrose/low-stachyose/low-raffinose seed phenotype originally observed in soybeans homozygous for the mips allele was reversed in the presence of mrp-l/mrp-n mutations: homozygous mips/mrp-l/mrp-n seed displayed low-sucrose (7.70%), high-stachyose (4.18%), and the highest observed raffinose (0.94%) contents per gram of dry seed. Perhaps the block in phytic acid transport from its cytoplasmic synthesis site to its storage site, conditioned by mrp-l/mrp-n, alters myo-inositol flux in mips seeds in a way that restores to wild-type levels the mips conditioned reductions in raffinosaccharides. Overall this study determined the combinatorial effects of three low phytic acid causing mutations on regulation of seed phytate and oligosaccharides in soybean.

Abstract Nanobiotechnology has the potential to revolutionize diverse sectors including medicine, agriculture, food, textile and pharmaceuticals. Disease diagnostics, therapeutics and crop protection strategies are fast emerging using nanomaterials preferably nanobiomaterials. It has potential for development of novel nanobiomolecules which offer several advantages over conventional treatment methods. RNA nanoparticles with many unique features are promising candidates in disease treatment. The miRNAs are involved in many biochemical and developmental pathways and their regulation in plants and animals. These appear to be a powerful tool for controlling various pathological diseases in human, plants and animals, however there are challenges associated with miRNA based nanotechnology. Several advancements made in the field of miRNA therapeutics make it an attractive approach, but a lot more has to be explored in nanotechnology assisted miRNA therapy. The miRNA based technologies can be employed for detection and combating crop diseases as well. Despite these potential advantages, nanobiotechnology applications in the agricultural sector are still in its infancy and have not yet made its mark in comparison with healthcare sector. The review provides a platform to discuss nature, role and use of miRNAs in nanobiotechnology applications.

Cluster bean [Cyamopsis tetragonoloba (L.) Taub] is an important leguminous crop of India, accounting for nearly 80% of the global production. The seeds of this economically important crop are used in various industrial applications worldwide like, textile, cosmetics, pharmaceuticals, mining, petroleum, natural gas, oil industries etc. Despite such high economic value, the productivity of this crop is quite low. One such major constraint in the production of cluster bean is bacterial leaf blight disease caused by Xanthomonas campestris pv. Cyamopsidis. Yield losses of up to 58–68% have been reported in case of severe infestation. Therefore, there is a need to formulate suitable breeding strategies to overcome the yield losses. But the lack of complete understanding of underlying genomic base in cluster bean is a major constraint in developing high-yielding and resistant cultivars/varieties. Here we report the first linkage map construction at the level of interspecific polymorphism using F3-4 segregating population based on Cyamopsis's the basis of microsatellite markers of cluster bean and other legume crops which can further advance the breeding programs. An interspecific cross was developed in our laboratory using a bacterial blight resistant wild species (C. serrata Schinz.) and a moderately susceptible with high gum content cultivar (HG563). A total of 177 SSRs comprising EST-SSRs from cluster bean and ESTs as well genomic SSRs from other legumes were used in molecular analysis and 38 SSRs were found polymorphic. Linkage analysis revealed that nine markers (CBN21, CBN16, CBN17, CTF234, CBN03, CBN11, CTN15, CTN14, and GDR22) formed a single linkage group spanning 190 cM of cluster bean genome. Four minor QTLs were identified in interspecific cross for plant height (qPH1.1), hundred seed weight (qHSW1.1), disease resistance (qPDI1.1), and gum content (qGC1.1) mapped on single linkage group at 39.41, 123.41, 112.41 and 102.41 cM, respectively. The LOD values for all four QTLs ranged from 3.3 to 15.5. (above the threshold LOD > 3.0). Marker interval of CTN15 and CTN14 spanning 35.4–190.0 cM distance harboured all the four QTLs. Interestingly, plant height QTL was found only 4.8 cM apart from CTN 15 SSR marker, which can be exploited further for cluster bean improvement programs in future. [ABSTRACT FROM AUTHOR]

Purpose: The study was conducted to study procrastination behavior among basic science undergraduate medical students using the previously validated procrastination assessment scale students (PASS). Frequency of and reasons for procrastination were compared among different subgroups of respondents. Methods: The study was conducted during the first two weeks of February 2017 using PASS. Gender, nationality and semester of study of the respondents were noted. PASS explores areas of and frequency of procrastination, reasons for procrastination and interest in changing the behavior. The frequency of procrastination, fear of failure, risk aversiveness, laziness and rebellion against control scores were compared among different subgroups using appropriate statistical tests. Results: A total of 107 students (84.9%) participated in the study. The mean frequency of procrastination score was 32.9 (maximum score 60). The score was significantly correlated with the respondents' gender. With regard to the percentage of students who nearly always or always procrastinated on a task, the percentages with regard to completing assignments, studying for exams, completing reading assignments, academic administrative tasks, attendance tasks and school activities in general were 25.2, 19.7, 25.2, 19.6, 18.7 and 17.7. The mean score for 'fear of failure' and 'aversiveness of task' as described by Solomon and Rothblum was 2.29 and 2.83. The mean scores for fear of failure, risk taking, and laziness were 26.17, 13.76 and 14.32. The median rebellion against control score was 6. Risk taking score was higher among respondents of other nationalities compared to Americans. Conclusions: Procrastination was regarded as a greater problem with regard to studying for exams and completing reading assignments and preparing for problem-based learning sessions. Only 42% of students were interested in attending a program to overcome procrastination. Similar studies among students during the clinical years are required. A study correlating self-reported procrastination with behavior can be carried out. Procrastination can also be studied in other offshore, Caribbean medical schools.