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Background and Objectives: Maize is a major ingredient of animal feed. However, its nutritional quality is poor due to the deficiency of essential amino acid methionine. The animal feed, prepared as a corn–legume mixture to balance the nutritional quality, remains deficient in methionine. Therefore, the bio‐fortification of maize for methionine is the best option to make nutritionally balanced animal and poultry feed. The present study was designed to evaluate the profile of zeins and the expression profile of methionine‐associated target genes in high‐ and low‐methionine maize. Findings: Results of sodium dodecyl sulfate‐polyacrylamide gel electrophoresis revealed that the 10‐kDa zein was accumulated during kernel development, and its accumulation was higher in high methionine lines. Gene expression analysis through real‐time polymerase chain reaction revealed that higher expression of 10‐ and 18‐kDa zeins is associated with higher methionine accumulation. Conclusions: The above results indicate that 10‐ and 18‐kDa genes are the potential targets for the methionine bio‐fortification in maize, which is required for animal and poultry feed. Significance and Novelty: The present study suggests that 10‐ and 18‐kDa genes are the major source of methionine, and the regulation of these genes is crucial to enhancing the methionine content in maize. The results indicate that these genes are potential targets for genetic engineering in maize to enhance methionine accumulation. [ABSTRACT FROM AUTHOR]

Background and Objectives: Zein proteins of maize endosperm are nutritionally poor, but important for vitreous kernel texture. The Opaque‐2 mutation enhances the protein quality but downregulates zein expression, distorting the kernel texture. Quality protein maize (QPM) is nutritionally improved, hard endosperm maize developed by introgression of endosperm modifiers under an opaque‐2 background. The present study aims to analyze the variability in zein expression patterns in normal, opaque‐2, and QPM lines through sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and two‐dimensional gel electrophoresis analyses. Findings: Results revealed that the total number of zein isoforms is almost similar in opaque‐2, normal, and QPM lines. Overall, in this study, it is concluded that the opaque‐2 mutation specifically affects the expression of high‐molecular‐weight zeins, which are being counterbalanced by the expression of low‐molecular‐weight zein isoforms and nonzein proteins. Conclusion: Genomic data retrieval studies revealed the possible presence of multiple 27 kDa isoforms with varied isoelectric points (pI), which is a subject for further investigation. The differential expression of 15 kDa zein in QPM emerged as a novel player in endosperm modification. Significance and Novelty: The present study provides insight into the diversified expression of zeins in different maize types. The variable isoform expression has the potential to generate stable QPM lines by targeting effective isoforms, ensuring endosperm modification without hampering the nutritional quality. [ABSTRACT FROM AUTHOR]

Maize serves as a crucial nutrient reservoir for a significant portion of the global population. However, to effectively address the growing world population’s hidden hunger, it is essential to focus on two key aspects: biofortification of maize and improving its yield potential through advanced breeding techniques. Moreover, the coordination of multiple targets within a single breeding program poses a complex challenge. This study compiled mapping studies conducted over the past decade, identifying quantitative trait loci associated with grain quality and yield related traits in maize. Meta-QTL analysis of 2,974 QTLs for 169 component traits (associated with quality and yield related traits) revealed 68 MQTLs across different genetic backgrounds and environments. Most of these MQTLs were further validated using the data from genome-wide association studies (GWAS). Further, ten MQTLs, referred to as breeding-friendly MQTLs (BF-MQTLs), with a significant phenotypic variation explained over 10% and confidence interval less than 2 Mb, were shortlisted. BF-MQTLs were further used to identify potential candidate genes, including 59 genes encoding important proteins/products involved in essential metabolic pathways. Five BF-MQTLs associated with both quality and yield traits were also recommended to be utilized in future breeding programs. Synteny analysis with wheat and rice genomes revealed conserved regions across the genomes, indicating these hotspot regions as validated targets for developing biofortified, high-yielding maize varieties in future breeding programs. After validation, the identified candidate genes can also be utilized to effectively model the plant architecture and enhance desirable quality traits through various approaches such as marker-assisted breeding, genetic engineering, and genome editing. [ABSTRACT FROM AUTHOR]

Introduction: Diabetic Retinopathy (DR) is one of the common microvascular complications of diabetes. In patients with DR, the most frequent cause of vision loss is Diabetic Macular oedema (DME). In the present era, anti-Vascular Endothelial Growth Factor (anti-VEGF) agents are the mainstay of treatment for managing DME. A majority of patients show a good response to multiple doses of these agents administered by a pro re nata regimen at regularly spaced fixed intervals. However, the tendency of DME to become chronic and resistant to these agents, as well as the burden of repeated injections, necessitates considering alternative treatment options with similar or better efficacy. As steroids can address these drawbacks of anti-VEGF treatment, the present study compared the efficacy of anti-VEGF agents with dexamethasone implant in the treatment of naïve DME. Aim: To compare the effectiveness of dexamethasone implant with anti-VEGF agents in the treatment of naïve DME. Materials and Methods: A prospective cohort study was conducted in the Department of Ophthalmology at Kalinga Institute of Medical Sciences and Pradyumna Bal Memorial Hospital, Bhubaneswar, Odisha, India from September 2020 to September 2022. A total of 100 eyes with DME, newly diagnosed patients aged 18 years and above, without other macular oedema-causing diseases, were included. A total of 50 eyes in each group were treated with an anti-VEGF agent (Group A) or dexamethasone implant (Group B), and Best Corrected Visual Acuity (BCVA) and Central Foveal Thickness (CFT) were monitored for six months. For statistical analysis, paired t-test and independent t-test were used for within-group and inter-group analysis, respectively. A p-value <0.05 was considered statistically significant. Results: In both groups, post-treatment BCVA showed marked improvement, but there was no significant difference in mean BCVA between the groups (p=0.89) at six months. However, the mean CFT showed significant improvement in Group B at six months. In Group A, the mean CFT reduced from 441.87±54.48 µm to 257.83±25.73 µm, and in Group B, the mean CFT reduced from 464±109.44 µm to 207±22.51 µm at six months (p<0.0001). Adverse events like cataracts and glaucoma were seen in patients treated with the dexamethasone implant and were managed by cataract surgery and topical anti-glaucoma medications, respectively. Conclusion: Dexamethasone implant and anti-VEGF agents are equally effective in improving visual acuity; however, dexamethasone stands superior in reducing macular thickness. Needing fewer injections while treating with a dexamethasone implant improves compliance. The progression of cataract remains a major side-effect with the dexamethasone implant, which is not a concern when treating DME in pseudophakic eyes. [ABSTRACT FROM AUTHOR]

Maize (Zea mays) is the most important coarse cereal utilized as a major energy source for animal feed and humans. However, maize grains are deficient in methionine, an essential amino acid required for proper growth and development. Synthetic methionine has been used in animal feed, which is costlier and leads to adverse health effects on end-users. Bio-fortification of maize for methionine is, therefore, the most sustainable and environmental friendly approach. The zein proteins are responsible for methionine deposition in the form of d-zein, which are major seed storage proteins of maize kernel. The present review summarizes various aspects of methionine including its importance and requirement for different subjects, its role in animal growth and performance, regulation of methionine content in maize and its utilization in human food. This review gives insight into improvement strategies including the selection of natural high-methionine mutants, molecular modulation of maize seed storage proteins and target key enzymes for sulphur metabolism and its flux towards the methionine synthesis, expression of synthetic genes, modifying gene codon and promoters employing genetic engineering approaches to enhance its expression. The compiled information on methionine and essential amino acids linked Quantitative Trait Loci in maize and orthologs cereals will give insight into the hotspot-linked genomic regions across the diverse range of maize germplasm through meta-QTL studies. The detailed information about candidate genes will provide the opportunity to target specific regions for gene editing to enhance methionine content in maize. Overall, this review will be helpful for researchers to design appropriate strategies to develop highmethionine maize. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to assess the quality of life (QOL) in glaucoma patients and find out the sociodemographic factors predicting QOL. Methods: A cross-sectional study was conducted in a tertiary care center from August 2021 to February 2022. Subjects diagnosed with glaucoma for at least 6 months were enrolled. After taking informed consent, demographic details and detailed history were collected for all patients. Comprehensive eye examination (visual acuity, intraocular pressure, gonioscopy, fundoscopy, visual field assessment, ocular coherence tomogram assessment) was done for all and they were asked to fill the WHOQOL-BREF questionnaire. Data were collected and analyzed using SPSS 21. Results: One hundred and ninety-nine patients were recruited. Mean age of participants was 57.99 ± 10.76 years. Based on various domains and subgroups, QOL values were significant with respect to income (P = 0.016). Gender-wise QOL in females was lower than that of males with respect to all the domains (P = 0.001). While marital status affected both environmental and social domain, literacy affected only the social domain. A variation in intraocular pressure affected the QOL in the psychological domain. QOL was not significantly associated with the severity of the disease. Gender was the most predominant predictor out of all sociodemographic factors. Conclusion: Chronic diseases affect the QOL of individuals in many ways. Glaucoma being a chronic disease hampers patients' vision irreversibly and by extension the various physical, social, and psychological aspects of the patient's life as well. Hence, knowledge of the change in QOL it brings about can help plan the treatment, counseling, and management of these patients. [ABSTRACT FROM AUTHOR]

The phenomenal increase in the use of nitrogenous fertilizers coupled with poor nitrogen use efficiency is among the most important threats to the environment, economic, and social health. During the last 2 decades, a number of genomic regions associated with nitrogen use efficiency (NUE) and related traits have been reported by different research groups, but none of the stable and major effect QTL have been utilized in the marker-assisted introgression/pyramiding program. Compiling the data available in the literature could be very useful in identifying stable and major effect genomic regions associated with the root and NUE-related trait improving the rice grain yield. In the present study, we performed meta-QTL analysis on 1,330 QTL from 29 studies published in the past 2 decades. A total of 76 MQTL with a stable effect over different genetic backgrounds and environments were identified. The significant reduction in the confidence interval of the MQTL compared to the initial QTL resulted in the identification of annotated and putative candidate genes related to the traits considered in the present study. A hot spot region associated with correlated traits on chr 1, 4, and 8 and candidate genes associated with nitrate transporters, nitrogen content, and ammonium uptake on chromosomes 2, 4, 6, and 8 have been identified. The identified MQTL, putative candidate genes, and their orthologues were validated on our previous studies conducted on rice and wheat. The research-based interventions such as improving nitrogen use efficiency via identification of major genomic regions and candidate genes can be a plausible, simple, and low-cost solution to address the challenges of the crop improvement program. [ABSTRACT FROM AUTHOR]

Nitrogen is one of the most important macronutrients for crop growth and metabolism. To identify marker-trait associations for complex nitrogen use efficiency (NUE)-related agronomic traits, field experiments were conducted on nested synthetic wheat introgression libraries at three nitrogen input levels across two seasons. The introgression libraries were genotyped using the 35K Axiom® Wheat Breeder's Array and genetic diversity and population structure were examined. Significant phenotypic variation was observed across genotypes, treatments, and their interactions across seasons for all the 22 traits measured. Significant positive correlations were observed among grain yield and yield-attributing traits and root traits. Across seasons, a total of 233 marker-trait associations (MTAs) associated with fifteen traits of interest at different levels of nitrogen (N0, N60, and N120) were detected using 9,474 genome-wide single nucleotide polymorphism (SNP) markers. Of these, 45 MTAs for 10 traits in the N0 treatment, 100 MTAs for 11 traits in the N60 treatment, and 88 MTAs for 11 traits in the N120 treatment were detected. We identified putative candidate genes underlying the significant MTAs which were associated directly or indirectly with various biological processes, cellular component organization, and molecular functions involving improved plant growth and grain yield. In addition, the top 10 lines based on N response and grain yield across seasons and treatments were identified. The identification and introgression of superior alleles/donors improving the NUE while maintaining grain yield may open new avenues in designing next generation nitrogen-efficient high-yielding wheat varieties. [ABSTRACT FROM AUTHOR]

Yellow maize is natural source of provitamin A components. However, the provitamin A carotenoids are known to degrade fast as a result of oxidation and isomerization due to exposure to heat and oxygen during storage. Keeping this in view, here, we evaluated the provitamin A carotenoids in maize stored under different storage conditions. For this purpose, F2 grains of six hybrids consisting of two provitamin A rich, two QPM and two normal maize were stored in earthen pot, aluminium box, cotton cloth and jute bag for a period of 6 months under ambient temperature and carotenoid components were estimated at monthly interval. Provitamin A components are found to reduce significantly within two to six months under various storage conditions. However, the samples stored in aluminium box exhibited least degradation of ß-carotene (73%) and ß-cryptoxanthin (81%), whereas those stored in earthen pot exhibited highest degradation of ß-carotene (86%) and ß-cryptoxanthin (90%), after six months of storage. The provitamin A rich hybrids especially APH27 retained highest concentration of provitamin A carotenoids after six months of storage. The least losses observed in the samples stored in aluminium box may be attributed to reduced oxidation and least light penetration. [ABSTRACT FROM AUTHOR]

Wheat is grown on more than 240 million hectares globally, more than any other commercial crop. Variation for nitrogen-use efficiency (NUE) in wheat germplasm is very important as efficiency of nitrogen fertilizers use can have significant effect on overall consumption of N. In the present study we used nested synthetic hexaploid wheat introgression libraries to detect genetic variation associated with NUE and related traits. The libraries were genotyped with 9474 SNP markers and used for genome-wide association mapping. Significant phenotypic variation was observed for all measured and derived traits. We detected 10 Quantitative trait locus (QTL) and 19 marker-trait associations (MTAs) possibly involved in improving NUE. Of these, 5 QTL and 8 MTAs detected under nitrogen-limited conditions have potential for use in breeding to increase nitrogen-deficiency tolerance. Nitrate transporter genes collocated with detected MTAs showed significant changes in expression of TaNRT2 genes in response to N-starvation and N-recovery. The identified promising breeding lines with stable yield, better NUE and acceptable protein content may constitute an important genetic resource in improving NUE of modern wheat varieties. • To meet future wheat production demands, improving nitrogen use while maintaining grain yield is vital. • We identified marker-trait associations improving nitrogen use efficiency while maintaining grain yield under varying nitrogen levels. • We also identified promising breeding lines with significant genetic variations and carrying the trait-associated markers or candidate genes. • These may serve as potential donors to be exploited further in genomics-assisted breeding programs targeting improved NUE while maintaining grain yield in wheat. [ABSTRACT FROM AUTHOR]

The development and utilization of molecular-markers play an important role in genomics-assisted breeding during pyramiding of valuable genes. The aim of present study was to develop and validate a novel core-set of KASP (Kompetitive Allele-Specific PCR) markers associated with traits improving rice grain yield and adaptability under direct-seeded cultivation conditions. The 110 phenotypically validated KASP assays out of 171 designed KASP, include assays for biotic-resistance genes, anaerobic germination, root-traits, grain yield, lodging resistance and early-uniform emergence. The KASP assays were validated for their robustness and reliability at five different levels using diverse germplasm, segregating and advanced population, comparison with SSR markers and on F 1s. The present research work will provide (i) breeding material in form of anticipated pre-direct-seeded adapted rice varieties (ii) single improved breeding line with many useful genes and (iii) KASP assay information for the useful QTL/genes providing grain yield and adaptability to rice under direct-seeded cultivation conditions. • A set of core 110 KASP arrays for genes/QTL associated with biotic resistance/tolerance, grain yield and adaptability under DSR was developed. • The KASP assays could significantly accelerate the genetic characterization of crossing parents and improved advanced breeding lines for GAB. • Our results offer a robust and reliable KASP toolkit that can contribute towards enhancing genetic gains in DSR breeding programs. [ABSTRACT FROM AUTHOR]

Nitrogen is an essential nutrient required in large quantities for the proper growth and development of plants. Nitrogen is the most limiting macronutrient for crop production in most of the world's agricultural areas. The dynamic nature of nitrogen and its tendency to lose soil and environment systems create a unique and challenging environment for its proper management. Exploiting genetic diversity, developing nutrient efficient novel varieties with better agronomy and crop management practices combined with improved crop genetics have been significant factors behind increased crop production. In this review, we highlight the various biochemical, genetic factors and the regulatory mechanisms controlling the plant nitrogen economy necessary for reducing fertilizer cost and improving nitrogen use efficiency while maintaining an acceptable grain yield., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sandhu, Sethi, Kumar, Dang, Singh and Chhuneja.)