Construction of a genome-wide genetic linkage map and identification of quantitative trait loci for powdery mildew resistance in Gerbera daisy

Powdery mildew (PM) is a common fungal disease in many important crops. The PM caused by Podosphaera xanthii has been the most challenging problem in commercial Gerbera (Gerbera hybrida) production globally, often leading to severe losses of crop yield and quality. A small number of PM-resistant breeding lines and cultivars have been reported in Gerbera, but the underlying genetics for PM resistance in Gerbera is largely unknown. Scarcity of genomic resources such as genetic linkage maps and molecular markers has severely hindered the effort to understand the genetic basis and locate loci controlling PM resistance in Gerbera. This study aimed to construct a genome-wide genetic linkage map, identify quantitative trait loci (QTL), and molecular markers for PM resistance in Gerbera. A segregating mapping population was developed by crossing PM-resistant and -susceptible Gerbera breeding lines, genotyped by sequencing, and phenotyped for PM resistance. A genome-wide genetic linkage map constructed with 791 single polymorphic site (SNP) markers spans 1912.30 cM across 27 linkage groups (LG) and reaches a density of 1 marker per 2.42 cM. One major consistent QTL was discovered in LG16, explaining more than 16.6% of the phenotypic variance for PM resistance. The QTL was tagged with two flanking SNP markers. The availability of this genetic linkage map will be very useful for locating and tagging QTLs for other important traits in Gerbera, and the newly discovered QTL and SNP markers will enable development of molecular markers for improving Gerbera for resistance to PM

Impact of comorbidity on patients with COVID-19 in India: A nationwide analysis

BackgroundThe emergence of coronavirus disease (COVID-19) as a global pandemic has resulted in the loss of many lives and a significant decline in global economic losses. Thus, for a large country like India, there is a need to comprehend the dynamics of COVID-19 in a clustered way.ObjectiveTo evaluate the clinical characteristics of patients with COVID-19 according to age, gender, and preexisting comorbidity. Patients with COVID-19 were categorized according to comorbidity, and the data over a 2-year period (1 January 2020 to 31 January 2022) were considered to analyze the impact of comorbidity on severe COVID-19 outcomes.MethodsFor different age/gender groups, the distribution of COVID-19 positive, hospitalized, and mortality cases was estimated. The impact of comorbidity was assessed by computing incidence rate (IR), odds ratio (OR), and proportion analysis.ResultsThe results indicated that COVID-19 caused an exponential growth in mortality. In patients over the age of 50, the mortality rate was found to be very high, ~80%. Moreover, based on the estimation of OR, it can be inferred that age and various preexisting comorbidities were found to be predictors of severe COVID-19 outcomes. The strongest risk factors for COVID-19 mortality were preexisting comorbidities like diabetes (OR: 2.39; 95% confidence interval (CI): 2.31–2.47; p < 0.0001), hypertension (OR: 2.31; 95% CI: 2.23–2.39; p < 0.0001), and heart disease (OR: 2.19; 95% CI: 2.08–2.30; p < 0.0001). The proportion of fatal cases among patients positive for COVID-19 increased with the number of comorbidities.ConclusionThis study concluded that elderly patients with preexisting comorbidities were at an increased risk of COVID-19 mortality. Patients in the elderly age group with underlying medical conditions are recommended for preventive medical care or medical resources and vaccination against COVID-19

A roadmap for research in octoploid strawberry

The cultivated strawberry (Fragaria × ananassa) is an allo-octoploid species, originating nearly 300 years ago from wild progenitors from the Americas. Since that time the strawberry has become the most widely cultivated fruit crop in the world, universally appealing due to its sensory qualities and health benefits. The recent publication of the first high-quality chromosome-scale octoploid strawberry genome (cv. Camarosa) is enabling rapid advances in genetics, stimulating scientific debate and provoking new research questions. In this forward-looking review we propose avenues of research toward new biological insights and applications to agriculture. Among these are the origins of the genome, characterization of genetic variants, and big data approaches to breeding. Key areas of research in molecular biology will include the control of flowering, fruit development, fruit quality, and plant–pathogen interactions. In order to realize this potential as a global community, investments in genome resources must be continually augmented.Peer reviewe

SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion

Abstract: The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era

A PREDICTIVE GENETIC KNOWLEDGE FOR APPLE "FRESH SENSATION" PROVIDES INFORMATION TO INCREASE BREEDING EFFICIENCY IN WASHINGTON

Apple texture and flavor are fruit quality components that determine the success of new apple cultivars and consumer satisfaction. Better-tasting apples encourage greater consumption and health benefits. The combined suite of traits of apple acidity (tartness), crispness, and juiciness is here termed "fresh sensation". The Washington State University Apple Breeding Program (WABP) is dedicated to developing new apple cultivars with improved "fresh sensation" among other attributes, and seeks to apply trait-predictive DNA tests to optimize breeding efficiency. Co-localized quantitative trait loci (QTLs) were previously reported for "fresh sensation" traits at the Ma locus of linkage group (LG) 16 of the apple genome. Two major alleles, Ma and ma associated with high and low acidity were identified in studies of biparental populations. Recently, the RosBREED project established resources (such as reference germplasm sets phenotyped with standardized protocols and genotyped with genome-wide single nucleotide polymorphism [SNP] markers), tools (such as Pedigree-Based Analysis software), and approaches (such as the "Marker-Assisted Breeding Pipeline") to characterize "fresh sensation" QTLs in breeding germplasm and develop predictive DNA tests. QTL analyses must be conducted to confirm the presence of contrasting alleles in WABP germplasm. Determination of SNP-based haplotypes associated with QTL alleles, their effects, and their distribution in the RosBREED WABP breeding germplasm will provide DNA information to support parent crossing decisions. Besides the Ma locus, other loci with genetic variation may also exist. This study seeks to confirm the presence of contrasting alleles at the Ma locus in RosBREED WABP breeding germplasm, and other QTLs for acidity as components of "fresh sensation", to determine the effects of each allele. A genome-wide QTL analysis was conducted using FlexQTLTM software. QTLs were validated at the Ma locus and on LG8, here called the "A" locus (for acidity). A QTL for crispness was also detected elsewhere on LG16. Relative effects of Ma and A haplotypes were calculated for each "fresh sensation" component. Three Ma alleles (Ma, ma and med) were identified at the Ma locus. The DNA information generated will help enable for marker-assisted parent selection to develop new apple cultivars using target levels of "fresh sensation" traits

Live plant and artificial plant settings are able to alleviate anxiety levels in mice an elevated plus-maze study

It has been established that green plant settings around humans can alleviate anxiety, and there is evidence that the response may be partly innate. This experiment was designed to find out if a similar innate response occurs in rodents. Elevated Plus-mazes have been used to measure anxiety levels in mice in pharmacological studies. They consist of 2 open arms and 2 closed arms. A less anxious mouse is expected to explore the open arm more frequently and stay there for longer periods of time. In this experiment, there were two treatment groups and a control. The control had nothing around the maze, the live plant treatment had live plants at the ends of each arm, and the artificial plant treatment used silk plants that resembled the live plants. Number of entries and time spent in open and closed arms was measured and analyzed using Mixed Linear Models Procedure in SAS. Mice spent significantly more time exploring the open arms during the live plant treatment than in the control (P < 0.001) or artificial plant treatment (P < 0.035). Animals in the artificial plant treatment also spent significantly more time in the open arms than in the control (P < 0.021). In addition, the percentage of entries made by live plant treatment mice into the open arms was significantly higher than in the control (P<0.002) and in artificial plant treatment (P<0.007) as well. However, it was not significantly different from artificial plant treatment mice (P< 0.199). In conclusion, this study showed that mice also appear to respond innately to nature. In this elevated plus-maze study, naïve mice were found to be the least anxious when exposed to the live plant environment and most anxious in the no plant environment. Response in the artificial plant environment was intermediate. While the response was strong, the fact that the differences between live and artificial plants were not always significant indicates that a better design is required in order to provide a good model system for studying this effect

The Experimental Investigation of a Diesel Engine Using Ternary Blends of Algae Biodiesel, Ethanol and Diesel Fuels

Algae are regarded among the most favorable feedstocks for producing sustainable biodiesel and utilizing it in diesel engines. Additionally, ethanol addition further enhanced the performance and reduce greenhouse emission. Algae biodiesel was produced, and an experimental study was performed to understand the diesel engine performance and emissions characteristics using different fuel blends by varying the ratio of diesel, biodiesel, and ethanol, such as D100, B10, B20, B5E5, and B10E10 (where number shows the percentage of the respective fuel). It was found that brake thermal efficiency was reduced by 0.49% and 1.29% for B10 and B20 blends, while the addition of ethanol enhanced the BTE by 0.37% and 1.60% respectively. However, SFC increases by 1.45%, 2.14%, 3.18%, and 3.78% respectively for B10, B20, B5E5, and B10E10 with respect to diesel fuel. Combustion characteristics were increased with increasing concentration of biodiesel and ethanol addition. Particulate matter, smoke emissions, and CO2 were slightly reduced by 3%, 4%, and 0.18%, respectively, while NOx emissions were increased by 26% for B10 blended fuel as compared to diesel fuel. Further addition of 5% (volume) ethanol in B5 fuel reduced particulate matter, smoke emissions, and CO2 emissions by 26.4%, 22%, and 23% respectively. Among the tested blends (B10, B20, B5E5, and B10E10), ethanol blended fuel was found to be more promising due to its higher combustion and performance and to have lower emissions to diesel fuel

Evaluation of the utility of the Fournier′s gangrene severity index in the management of Fournier′s gangrene in North India: A multicentre retrospective study

Objective: To study the utility of Fournier′s Gangrene Severity Index (FGSI) with mortality predictive value in our tertiary institutes in North India. Materials and Methods: A retrospective study of 95 cases of Fournier′s Gangrene (FG), admitted from 2009 to 2011, was carried out. We analysed clinical and laboratory findings, various prognostic factors, surgical treatments and their outcomes in FG patients. FGSI was used as individual variable to estimate the severity of FG; the effects of these factors on mortality were also evaluated. Results: The overall mean age was 46.5 ± 15.6 (range 24-82) years. Anorectal and urological regions were the main sites of the infection. The most common site of infection origin was scrotum in 81.3% in group A and 41.2% in group B. One or more predisposing factors such as diabetes mellitus (DM; 55%) malignancies (4.6%), chronic renal failure (4.5%) and previous surgery (9.2%) were detected. We observed mortality in 26.5% cases (17/65). The FGSI calculated averaged 5.95 ± 365 in group A and 9.44 ± 2.56 in group B, at the time of admission ( P > 0.05). Conclusion: In FG, an early diagnosis and early surgical debridement are essential. The FGSI seems to be an excellent tool for the outcome prediction

COVID-19 pandemic: Insights into structure, function, and hACE2 receptor recognition by SARS-CoV-2

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a newly emerging, highly transmissible, and pathogenic coronavirus in humans that has caused global public health emergencies and economic crises. To date, millions of infections and thousands of deaths have been reported worldwide, and the numbers continue to rise. Currently, there is no specific drug or vaccine against this deadly virus; therefore, there is a pressing need to understand the mechanism(s) through which this virus enters the host cell. Viral entry into the host cell is a multistep process in which SARS-CoV-2 utilizes the receptor-binding domain (RBD) of the spike (S) glycoprotein to recognize angiotensin-converting enzyme 2 (ACE2) receptors on the human cells; this initiates host-cell entry by promoting viral–host cell membrane fusion through large-scale conformational changes in the S protein. Receptor recognition and fusion are critical and essential steps of viral infections and are key determinants of the viral host range and cross-species transmission. In this review, we summarize the current knowledge on the origin and evolution of SARS-CoV-2 and the roles of key viral factors. We discuss the structure of RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 and its significance in drug discovery and explain the receptor recognition mechanisms of coronaviruses. Further, we provide a comparative analysis of the SARS-CoV and SARS-CoV-2 S proteins and their receptor-binding specificity and discuss the differences in their antigenicity based on biophysical and structural characteristics