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Context: Untapped wheat germplasm is conserved globally in genebanks. Evaluating it for grain quality and yield will help achieve nutritional and food security. Aims: We aimed to evaluate the Indian National Genebank bread wheat core collection for grain quality, phenology and yield, to identify potential donor germplasm. Methods: 1485 accessions were grown at three locations in India during winter 2015–2016 to evaluate test weight, grain protein content, sedimentation value (SV), days to spike emergence, days to maturity, grain yield and thousand-grain weight (TGW). Key results: Best linear unbiased estimates indicated mean protein of 13.3%, 14.7%, and 13.0% and yield of 73.0 g/m, 70.9 g/m and 66.6 g/m at Ludhiana, Pune, and Varanasi locations, respectively. The SV ranged from 26.6–65.6 mL and 17.7–66.6 mL at the Ludhiana and Pune locations, respectively. The top 10 accessions were identified for all the studied traits. Six high protein accessions, with consistent protein of more than 15% along with moderate Thousand-grain and test weights were further validated and assessed for stability across environments. Grain protein content was correlated negatively with thousand-grain weight and yield, but positively with days to maturity and spike emergence. Conclusion: The identified accessions with high trait values could be used in future breeding programmes to develop high yielding biofortified cultivars to address protein malnutrition and also cultivars with suitable end-product quality. Implications: The diversity in a core collection can be exploited to develop modern high yielding bread wheat cultivars with higher grain protein content and suitable end-product quality. To eliminate hunger and malnutrition, genetic resources for cereals with high grain protein content, grain yield, and other quality traits are needed. A diverse and representative set of bread wheat genetic resources is extracted from national genebank of India. We evaluated this diverse core collection across multiple environments to find novel and stable high yielding germplasm with superior grain quality for further use. [ABSTRACT FROM AUTHOR]

Powdery mildew (PM), caused by Blumeria graminis f. sp. tritici, poses a significant threat to wheat production, necessitating the development of genetically resistant varieties for long-term control. Therefore, exploring genetic architecture of PM in wheat to uncover important genomic regions is an important area of wheat research. In recent years, the utilization of meta-QTL (MQTL) analysis has gained prominence as an essential tool for unraveling the complex genetic architecture underlying complex quantitative traits. The aim of this research was to conduct a QTL meta-analysis to pinpoint the specific genomic regions in wheat responsible for governing PM resistance. This study integrated 222 QTLs from 33 linkage-based studies using a consensus map with 54,672 markers. The analysis revealed 39 MQTLs, refined to 9 high-confidence MQTLs (hcMQTLs) with confidence intervals of 0.49 to 12.94 cM. The MQTLs had an average physical interval of 41.00 Mb, ranging from 0.000048 Mb to 380.71 Mb per MQTL. Importantly, 18 MQTLs co-localized with known resistance genes like Pm2, Pm3, Pm8, Pm21, Pm38, and Pm41. The study identified 256 gene models within hcMQTLs, providing potential targets for marker-assisted breeding and genomic prediction programs to enhance PM resistance. These MQTLs would serve as a foundation for fine mapping, gene isolation, and functional genomics studies, facilitating a deeper understanding of molecular mechanisms. The identification of candidate genes opens up exciting possibilities for the development of PM-resistant wheat varieties after validation. [ABSTRACT FROM AUTHOR]

Wheat is one of the major staple cereal food crops in India. However, most of the wheat-growing areas experience several biotic and abiotic stresses, resulting in poor quality grains and reduced yield. To ensure food security for the growing population in India, there is a compelling need to explore the untapped genetic diversity available in gene banks for the development of stress-resistant/tolerant cultivars. The improvement of any crop lies in exploring and harnessing the genetic diversity available in its genetic resources in the form of cultivated varieties, landraces, wild relatives, and related genera. A huge collection of wheat genetic resources is conserved in various gene banks across the globe. Molecular and phenotypic characterization followed by documentation of conserved genetic resources is a prerequisite for germplasm utilization in crop improvement. The National Genebank of India has an extensive and diverse collection of wheat germplasm, comprising Indian wheat landraces, primitive cultivars, breeding lines, and collection from other countries. The conserved germplasm can contribute immensely to the development of wheat cultivars with high levels of biotic and abiotic stress tolerance. Breeding wheat varieties that can give high yields under different stress environments has not made much headway due to high genotypes and environmental interaction, non-availability of truly resistant/tolerant germplasm, and non-availability of reliable markers linked with the QTL having a significant impact on resistance/tolerance. The development of new breeding technologies like genomic selection (GS), which takes into account the G × E interaction, will facilitate crop improvement through enhanced climate resilience, by combining biotic and abiotic stress resistance/tolerance and maximizing yield potential. In this review article, we have summarized different constraints being faced by Indian wheat-breeding programs, challenges in addressing biotic and abiotic stresses, and improving quality and nutrition. Efforts have been made to highlight the wealth of Indian wheat genetic resources available in our National Genebank and their evaluation for the identification of trait-specific germplasm. Promising genotypes to develop varieties of important targeted traits and the development of different genomics resources have also been highlighted. [ABSTRACT FROM AUTHOR]

Blumeria graminis (DC). E.U. Speer f.sp. tritici Em. Marchal (Syn. Erysiphe graminis DC f.sp. tritici, Em. Marchal), a causal organism of powdery mildew (PM), is one of the important diseases of wheat worldwide. A comprehensive evaluation of wheat germplasm accessions (19,460) conserved in the National Genebank of ICAR–National Bureau of Plant Genetic Resources was conducted to identify sources of resistance to PM. Accessions belonging to the three wheat species—bread wheat (Triticum aestivum L. subsp. aestivum) (15,944), durum wheat (T. durum Desf.) (3,359), and emmer wheat (T. dicoccum Schrank ex Schübl.) (157)—were screened at Wellington, a hotspot location for PM, for two consecutive seasons. Screening results indicated that 7271 (45%) from bread wheat, 756 (22%) from durum wheat, and 22 (14%) from emmer were resistant. Out of 8094 PM‐resistant accessions, 60% were indigenous, while majority of the 40% exotic were from CIMMYT. Focused identification of germplasm strategy (FIGS), which identifies a set of similar plant genotypes with a greater possibility of containing specific target traits, was used to form a subset of 52 accessions (from 19,460) that have the potential to contain new PM resistance genes. Resistant accessions identified in the study have enriched the existing gene pool for PM resistance in wheat and will serve as a potential source for resistance in future. [ABSTRACT FROM AUTHOR]

Leaf rust (Puccinia triticina Eriks.) is a fungal disease of wheat (Triticum spp.), which causes considerable yield loss. Adult plant resistance (APR) is one of the most sustainable approaches to control leaf rust. In this study, field-testing was carried out across ten different locations, followed by molecular screening, to detect the presence of APR genes, Lr34+, Lr46+, Lr67+ and Lr68 in Indian wheat germplasm. In field screening, 190 wheat accessions were selected from 6,319 accessions based on leaf tip necrosis (LTN), disease severity and the average coefficient of infection. Molecular screening revealed that 73% of the accessions possessed known APR genes either as single or as a combination of two or three genes. The occurrence of increased LTN intensity, decreased leaf rust severity and greater expression of APR genes were more in relatively cooler locations. In 52 lines, although the presence of the APR genes was not detected, it still displayed high levels of resistance. Furthermore, 49 accessions possessing either two or three APR genes were evaluated for stability across locations for grain yield. It emerged that eight accessions had wider adaptability. Resistance based on APR genes, in the background of high yielding cultivars, is expected to provide a high level of race non-specific resistance, which is durable. [ABSTRACT FROM AUTHOR]

Stem rust is one of the major diseases threatening wheat production globally. To identify novel resistance quantitative trait loci (QTLs), we performed 35K Axiom Array SNP genotyping assays on an association mapping panel of 400 germplasm accessions, including Indian landraces, in conjunction with phenotyping for stem rust at seedling and adult plant stages. Association analyses using three genome wide association study (GWAS) models (CMLM, MLMM, and FarmCPU) revealed 20 reliable QTLs for seedling and adult plant resistance. Among these 20 QTLs, five QTLs were found consistent with three models, i.e., four QTLs on chromosome 2AL, 2BL, 2DL, and 3BL for seedling resistance and one QTL on chromosome 7DS for adult plant resistance. Further, we identified a total of 21 potential candidate genes underlying QTLs using gene ontology analysis, including a leucine rich repeat receptor (LRR) and P-loop nucleoside triphosphate hydrolase, which have a role in pathogen recognition and disease resistance. Furthermore, four QTLs ( Qsr.nbpgr-3B_11 , QSr.nbpgr-6AS_11 , QSr.nbpgr-2AL_117-6 , and QSr.nbpgr-7BS_APR ) were validated through KASP located on chromosomes 3B, 6A, 2A, and 7B. Out of these QTLs, QSr.nbpgr-7BS_APR was identified as a novel QTL for stem rust resistance which has been found effective in both seedling as well as the adult plant stages. Identified novel genomic regions and validated QTLs have the potential to be deployed in wheat improvement programs to develop disease resistant varieties for stem rust and can diversify the genetic basis of resistance., Competing Interests: The author(s) declare no conflict of interest.

Background: Intubation in the ICU is sometimes unpredictable unlike in an operation theatre, where pre-anesthetic assessment for airway has been done. This study has been done to evaluate the usefulness of hyomental distance ratio (HMDR) in accurately predicting difficult laryngoscopy in ICU patients., Methods: In this study, 104 critically ill patients in the age group 18-70 years, undergoing tracheal intubation in ICU were included. A hard plastic ruler was pressed on the skin surface just above the hyoid bone and the distance to the tip of the anterior-most part of the mentum measured was defined as hyomental distance (HMD). HMD was assessed in neutral and extended head positions, and the HMDR was calculated. All patients were sedated, pre-oxygenated, induced, and relaxed prior to glottic visualization by direct laryngoscopy, which was performed by an experienced anesthetist. Cormack-Lehane's (CL's) grade was assessed without external laryngeal manipulation. Further management was as per ICU protocol., Results: Using the Chi-Square test for statistical analysis, a p-value of HMDR in assessing difficult laryngoscopy was found to be <0.001 suggesting strong significance. HMD in the extended head position (HDMe) showed moderate significance with a p-value of 0.047. HMDR <1.2 can be considered a clinically reliable individual predictor of difficult laryngoscopy in ICU patients., Conclusion: HMDR <1.2 can be used as a simple, easy, and reliable bedside test to predict difficult laryngoscopy amongst ICU patients. An optimal combination of tests is suggested if feasible for better accuracy., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Hrithma et al.)

Background: The most commonly used equipment to aid endotracheal intubation is a laryngoscope, and the procedure performed is known as laryngoscopy, which leads to profound cardiovascular effects. The process of laryngoscopy causes the release of catecholamines, thereby leading to marked pressor responses and tachycardia. The process of laryngoscopy can be made easier by the use of various types of laryngoscopic blades. The McCoy blade is a modification of the standard Macintosh blade that incorporates a hinged tip blade. It allows elevation of the epiglottis while decreasing overall laryngeal movement. A Miller blade is a straight blade with a slight upward curve near the tip. It is found that the force exerted, head extension, and cervical spine movement are less with the Miller blade. This study was undertaken to compare changes in haemodynamic parameters before, during, and after laryngoscopy using these two blades., Materials and Methods: Following institutional ethical committee approval and obtaining informed written consent, 100 patients of American Society of Anesthesiologists (ASA) grades I and II in the age group of 18-45 years of either sex undergoing elective surgeries under general anaesthesia were included in the study. The patients were randomly allocated into two groups of 50 patients each. Group Mc - laryngoscopy was performed using a no. 3 McCoy blade. Group Ml - laryngoscopy was performed using a no. 2 Miller blade. The laryngoscopic view was compared using Cormack and Lehane grading. Haemodynamic parameters before, during, and after laryngoscopy were recorded., Results: Hemodynamic parameters including heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were increased in both the groups but were statistically and clinically significant in the Miller group with p≤0.001., Conclusion: McCoy blade is associated with a significantly more stable hemodynamic response to laryngoscopy in comparison with the Miller blade., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Mahadevaiah et al.)

Introduction Deterioration of clinical condition of in-hospital patients further leads to intensive care unit (ICU) transfer or death which can be reduced by the use of prediction tools. The early warning scoring (EWS) system is a prediction tool used in monitoring medical patients in hospitals, hospital staying length, and inpatient mortality. The present study evaluated four different EWS systems for the prediction of patient survival. Method The present prospective observational study has analyzed 217 patients visiting the emergency department from November 2016 to November 2018, followed by demographic and clinical data collection. Modified Early Warning Score (MEWS), Triage Early Warning Score (TEWS), Leed's Early Warning Score (LEWS), and patient-at-risk scores (PARS) were assigned based upon body temperature, consciousness level, heart rate, blood pressure, respiratory rate, mobility, etc. Data was analyzed with the help of R 4.0.4 (R Foundation, Vienna, Austria) and Microsoft Excel (Microsoft, Redmond, Washington). Results Out of these 217 patients, 205 got shifted to a ward, and 12 died, amongst which the majority belonged to the 31-40 age group. Among patients admitted to ICU had a MEWS greater than 3, TEWS within the range 0 to 2 and 3 to 5, LEWS greater than 7, and PARS greater than 5 on the initial days of admission. The patients who died and those who were shifted to the ward showed significant differences in EWS. A significant association was observed between all the EWS and patient outcomes (p<0.001). Conclusion MEWS, TEWS, LEWS, and PARS were effective in the prediction of inpatient mortality as well as admission to the ICU. With the increase in the EWS, there was an increase in the duration of ICU stay and a decrease in chances of survival., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, T P et al.)

Key Message: This work discusses several selected topics of plant genetics and breeding in relation to the 150th anniversary of the seminal work of Gregor Johann Mendel. In 2015, we celebrated the 150th anniversary of the presentation of the seminal work of Gregor Johann Mendel. While Darwin's theory of evolution was based on differential survival and differential reproductive success, Mendel's theory of heredity relies on equality and stability throughout all stages of the life cycle. Darwin's concepts were continuous variation and "soft" heredity; Mendel espoused discontinuous variation and "hard" heredity. Thus, the combination of Mendelian genetics with Darwin's theory of natural selection was the process that resulted in the modern synthesis of evolutionary biology. Although biology, genetics, and genomics have been revolutionized in recent years, modern genetics will forever rely on simple principles founded on pea breeding using seven single gene characters. Purposeful use of mutants to study gene function is one of the essential tools of modern genetics. Today, over 100 plant species genomes have been sequenced. Mapping populations and their use in segregation of molecular markers and marker-trait association to map and isolate genes, were developed on the basis of Mendel's work. Genome-wide or genomic selection is a recent approach for the development of improved breeding lines. The analysis of complex traits has been enhanced by high-throughput phenotyping and developments in statistical and modeling methods for the analysis of phenotypic data. Introgression of novel alleles from landraces and wild relatives widens genetic diversity and improves traits; transgenic methodologies allow for the introduction of novel genes from diverse sources, and gene editing approaches offer possibilities to manipulate gene in a precise manner.