Natesan Senthil

Purpose: The purpose of this review is to examine how provitamin A accumulation in maize, post-harvest retention, food processing, carotenoid bioavailability and host-specific bioconversion collectively influence vitamin A delivery, and to propose the delivered retinol activity equivalent (dRAE) framework for scenariobased assessment. Vitamin A deficiency (VAD) remains a major global public health problem, particularly in populations reliant on staple-based diets. Provitamin A (PVA)-biofortified maize has emerged as a sustainable food-based intervention to improve vitamin A intake. Design/methodology/approach: This study integrates current knowledge on the molecular basis of PVA accumulation, carotenoid stability, post-harvest retention and host factors affecting vitamin A utilization. Literature was collected from Web of Science, Scopus and PubMed using keywords related to PVA maize breeding, processing, storage and bioavailability. Priority was given to recent peer-reviewed high-quality studies reporting evidence on PVA concentration, carotenoid retention, bioavailability and bioconversion. Findings: Molecular breeding has increased kernel ß-carotene through key carotenoid pathway genes, including lcyE and crtRB1. However, kernel carotenoid concentration alone does not ensure effective vitamin A delivery. Post-harvest degradation during storage, processing and cooking, together with dietary and physiological factors, can substantially influence carotenoid availability and conversion to retinol. Host genetic variability, particularly polymorphisms in BCMO1, further contributes to differences in ß-carotene conversion efficiency. Practical implications: The dRAE framework provides a conceptual, scenario-based approach for considering crop composition, post-harvest retention, bioavailability and bioconversion together when evaluating the potential vitamin A contribution of PVA-biofortified maize. Originality/value: Effective vitamin A delivery from PVA-biofortified maize depends on kernel carotenoid concentration, post-harvest retention, bioavailability and bioconversion. The authors propose a delivery-oriented framework, Delivered Retinol Activity Equivalent (dRAE), to integrate these factors under specified conditions.

Background and Objectives: Maize ( Zea mays L.) is an important model for studying flavonoid biosynthesis and enhancing cereal nutritional value. Its diverse anthocyanin pigmentation across kernels, vegetative, and reproductive tissues makes it especially valuable. This review summarizes anthocyanin chemistry, genetic regulation, environmental influences, breeding strategies, and opportunities to develop anthocyanin‐enriched maize. Findings: Maize anthocyanins occur predominantly as glycosides of cyanidin, pelargonidin, and peonidin, with their biosynthesis regulated through coordinated interactions between structural and regulatory genes. The MYB–bHLH–WD40 (MBW) transcriptional complex plays a central role, where MYB transcription factors ( c1 and pl1 ) and bHLH regulators ( r1/b1 family) control tissue‐specific and developmental anthocyanin accumulation. The pr1 locus, encoding flavonoid 3′‐hydroxylase, directs pigment composition by determining cyanidin‐derived purple or pelargonidin‐derived red anthocyanins. Environmental factors, including light, temperature, and nutrient availability, further influence anthocyanin biosynthesis through gene expression. Recent advances in molecular breeding and marker‐assisted selection have enabled the identification and incorporation of favorable alleles, facilitating the development of anthocyanin‐rich maize with improved nutritional value and genetic stability. Conclusion: Coordinated genetic regulation via the MBW complex and the pr1 metabolic switch, together with environmental modulation, governs anthocyanin diversity in maize. Marker‐assisted breeding enables efficient introgression of favorable anthocyanin traits into elite germplasm, overcoming historical linkage drag and enhancing biofortification. Significance and Novelty: This review highlights the potential for developing anthocyanin‐enriched maize as a functional food and a sustainable alternative source of natural colorants.

Fall armyworm (FAW) is a major constraint in maize production and cause considerable yield loss. Although chemical control methods are being widely used for management of FAW, there are increasing concerns regarding issues like pesticide resistance and ecological imbalance. Exploiting host plant resistance represents the most eco-friendly and cost-effective approach. Growing resistant varieties are one of the ecofriendly approach in FAW management. A prime phase in the line of research is identification of resistant sources and underlying mechanisms contributing towards resistance. Present study integrates field screening, ovipositional preference assay, volatile profiling, and olfactory behavioural assays to characterize resistance in maize genotypes against FAW. Initial screening trials across two seasons revealed a dominance of susceptible genotypes, with DMRE 63 exhibiting resistance and CML 122 as moderate resistance. Leaf damage was highest at 14 days after infestation which corresponds to late larval feeding stage. Ovipositional preference study revealed DMRE 63 had lowest egg deposition under choice and no-choice conditions, indicating antixenosis. Induction of resistance is clearly evidenced through volatile profiling, showing distinct variation among genotypes in healthy, infested plants. Resistant genotype DMRE 63 produced biologically active aldehydes and inducible terpenoid–ketone compounds, whereas susceptible genotype CML 170 was dominated by structural hydrocarbons. Olfactometer assays confirmed behavioural avoidance of infested plants in resistant, moderately resistant, susceptible genotypes. Principal component analysis explained 96.7% variability, linking resistance to behavioural deterrence and reduced oviposition which are components of antixenosis mechanism. This study highlights the need to integrate field screening with chemical ecology ensuring sustainable pest management.

Sweet corn ( Zea mays L.) is a widely consumed vegetable crop; however, most commercial cultivars contain low levels of provitamin A carotenoids and anthocyanins, limiting their nutritional value. In this study, marker‐assisted backcross breeding was employed to simultaneously enhance beta‐carotene content, anthocyanin accumulation, and sweetness by introgressing the favourable crtRB1 allele, the recessive sh2 allele, and purple aleurone pigmentation into the elite sweet corn inbred DBT15 using the purple maize landrace Chujak Purple from the North‐Eastern Himalayan Region (NEHR) as the donor parent. Foreground selection for crtRB1 , phenotypic selection for purple kernel pigmentation and shrunken endosperm, and background selection using 102 polymorphic SSR markers facilitated the recovery of six stable BC ₂ F ₄ purple sweet corn introgression lines. Based on kernel pigmentation and anthocyanin composition, the lines were grouped into dark greyish‐purple and greyish‐purple types. At 24 days after pollination, the improved lines exhibited total soluble solids of 15.56–16.3°Brix, total sugars of 16.8%–17.57% and beta‐carotene concentrations of 7.25–8.20 μg/g, comparable to the recurrent parent DBT15 and substantially higher than the donor parent. High‐performance liquid chromatography identified cyanidin‐3‐glucoside, pelargonidin‐3‐glucoside and peonidin‐3‐glucoside as the predominant anthocyanins and evaluated across environments. These results demonstrate the successful development of biofortified purple super‐sweet corn combining enhanced provitamin A, elevated anthocyanin content and desirable sweetness, providing valuable germplasm for developing nutritionally superior sweet corn cultivars.

Moth bean ( Vigna aconitifolia ), a protein-rich, arid-adapted legume of considerable agronomic importance, lacks a whole genome assembly, limiting genome-enabled trait discovery and genetic improvement. In this study, we estimated its genome size using 31.28 Gb of Illumina short-read sequencing data, and a k-mer analysis (k = 21) predicted a genome size of 448.98 Mb. We generated a highly contiguous 420.3 Mb genome assembly using 37.04 Gb of PacBio HiFi long-read sequencing data, corresponding to 82.5× genome coverage. The assembly achieved a contig N50 of 22.30 Mb, with a maximum contig length of 59.6 Mb, and exhibited >98% completeness based on BUSCO assessment. Comparative genomic and phylogenetic analyses of 14 closely related species identified V. radiata and V. mungo as the closest extant relatives of moth bean, with an estimated divergence time of ~3.7 Mya, consistent with established phylogenetic relationships within the genus Vigna . Structural annotation predicted ~27,434 protein-coding genes, of which 27,411 (99.91%) were functionally annotated. Repetitive sequences accounted for 50.66% of the genome, with retrotransposons representing the predominant class and occupying 109.9 Mb (26.1%). We further identified 178 disease resistance–related genes and 54 genes involved in flavonoid biosynthesis, including those encoding key enzymes such as chalcone synthase, chalcone isomerase, flavanone 3-hydroxylase, and flavone synthase II. Collectively, we present the first highly contiguous moth bean genome assembly, providing a foundational resource for evolutionary, functional genomics and breeding studies. This resource facilitates characterization of genes governing disease resistance and flavonoid biosynthesis, supporting genetic improvement of stress tolerance and nutritional quality in moth bean.

Mungbean is an important legume crop native to India. In this study, 500 indigenous mungbean accessions collected from diverse eco-geographical regions of India were evaluated for agronomic trait genetic variability and core collection development. The accessions were grown in an augmented design during 2019 and 2020, and data were recorded for seven quantitative and 13 qualitative traits. Analysis of variance (ANOVA), frequency distribution, and box-plot analyses revealed substantial phenotypic variation among the accessions. Traits including plant height (PHT), number of pods per plant (NPP), hundred-seed weight (HSW), and single-plant yield (SPY) exhibited high heritability coupled with high genetic advance, indicating the predominance of additive genetic effects. Principal component analysis showed that the first three principal components explained 70% of the total phenotypic variation. The Shannon–Weaver diversity index further indicated high levels of genetic diversity within the population. Based on quantitative traits, the accessions were grouped into six major clusters and 42 sub-clusters, with SPY, NPP, HSW, PHT, and days to 50% flowering (DFF) contributing substantially to genetic divergence. Correlation analysis suggested that direct selection for SPY and indirect selection through associated traits, including NPP, HSW, PHT, NSP, and pod length (POL), may enhance yield improvement. The germplasm collection also possessed desirable traits such as high yield potential, contrasting maturity groups, and plant types suitable for mechanical harvesting and bold-seeded type. A representative core set comprising 50 accessions was developed using the PowerCore program, providing valuable genetic resources for mungbean breeding and genetic improvement programs.