Nitrogen at the crossroads of light: Integration of light signalling and plant nitrogen metabolism.

Plants have developed complex mechanisms to perceive, transduce, and respond to environmental signals, such as light, which are essential for acquiring and allocating resources, including nitrogen (N). This review delves into the complex interaction between light signals and N metabolism, emphasising light-mediated regulation of N uptake and assimilation. Firstly, we discuss the details of light-mediated regulation of N uptake and assimilation, focusing on the light-responsive activity of nitrate reductase (NR) and nitrate transporters.

miRNA mediated regulation of nitrogen response and nitrogen use efficiency of plants: the case of wheat.

Nitrogen (N) is needed for plant growth and development and is the major limiting nutrient due to its higher demand in agricultural production globally. The use of N fertilizers has increased considerably in recent years to achieve higher cereal yields. High N inputs coupled with declining N use efficiency (NUE) result in the degradation of the environment.

Calcium regulates primary nitrate response associated gene transcription in a time- and dose-dependent manner.

Nitrate (NO) is the primary source of nitrogen preferred by most arable crops, including wheat. The pioneering experiment on primary nitrate response (PNR) was carried out three decades ago. Since then, much research has been carried out to understand the NO signaling.

Phenomics based prediction of plant biomass and leaf area in wheat using machine learning approaches.

Introduction: Phenomics has emerged as important tool to bridge the genotype-phenotype gap. To dissect complex traits such as highly dynamic plant growth, and quantification of its component traits over a different growth phase of plant will immensely help dissect genetic basis of biomass production. Based on RGB images, models have been developed to predict biomass recently.

Long term nitrogen deficiency alters expression of miRNAs and alters nitrogen metabolism and root architecture in Indian dwarf wheat (Triticum sphaerococcum Perc.) genotypes.

The important roles of plant microRNAs (miRNAs) in adaptation to nitrogen (N) deficiency in different crop species especially cereals (rice, wheat, maize) have been under discussion since last decade with little focus on potential wild relatives and landraces. Indian dwarf wheat (Triticum sphaerococcum Percival) is an important landrace native to the Indian subcontinent. Several unique features, especially high protein content and resistance to drought and yellow rust, make it a very potent landrace for breeding.

Variation in nitrogen partitioning and reproductive stage nitrogen remobilization determines nitrogen grain production efficiency (NUEg) in diverse rice genotypes under varying nitrogen supply.

Nitrogen (N) is an important macronutrient needed for grain yield, grain N and grain protein content in rice. Grain yield and quality are significantly determined by N availability. In this study, to understand the mechanisms associated with reproductive stage N remobilization and N partitioning to grain 2 years of field experiments were conducted with 30 diverse rice genotypes during 2019-Kharif and 2020-Kharif seasons.

Upregulation of genes encoding plastidic isoforms of antioxidant enzymes and osmolyte synthesis impart tissue tolerance to salinity stress in bread wheat.

Unlabelled: Wheat genotype Kharchia is a donor for salt tolerance in wheat breeding programs worldwide; however, the tolerance mechanism in Kharchia is yet to be deciphered completely. To avoid spending energy on accumulating organic osmolytes and to conserve resources for maintaining growth, plants deploy sodium (Na) ions to maintain turgor. The enhanced ability to tolerate excess ion accumulation and ion toxicity is designated as tissue tolerance.

Genome-wide characterization and identification of cyclophilin genes associated with leaf rust resistance in bread wheat ( L.).

Cyclophilins (CYPs) are a group of highly conserved proteins involved in host-pathogen interactions in diverse plant species. However, the role of CYPs during disease resistance in wheat remains largely elusive. In the present study, the systematic genome-wide survey revealed a set of 81 genes from three subfamilies (GI, GII, and GIII) distributed on all 21 wheat chromosomes.

Integrated breeding approaches to enhance the nutritional quality of food legumes.

Global food security, both in terms of quantity and quality remains as a challenge with the increasing population. In parallel, micronutrient deficiency in the human diet leads to malnutrition and several health-related problems collectively known as "hidden hunger" more prominent in developing countries around the globe. Biofortification is a potential tool to fortify grain legumes with micronutrients to mitigate the food and nutritional security of the ever-increasing population.

Genome Editing Targets for Improving Nutrient Use Efficiency and Nutrient Stress Adaptation.

In recent years, the development of RNA-guided genome editing (CRISPR-Cas9 technology) has revolutionized plant genome editing. Under nutrient deficiency conditions, different transcription factors and regulatory gene networks work together to maintain nutrient homeostasis. Improvement in the use efficiency of nitrogen (N), phosphorus (P) and potassium (K) is essential to ensure sustainable yield with enhanced quality and tolerance to stresses.

Genome-Wide Identification and Expression Analysis of the Thioredoxin () Gene Family Reveals Its Role in Leaf Rust Resistance in Wheat ( L.).

Bread wheat ( L.; ) is the staple cereal crop for the majority of the world's population. Leaf rust disease caused by the obligate fungal pathogen, L.

Interactive effect of elevated CO and nitrogen dose reprograms grain ionome and associated gene expression in bread wheat.

Wheat crop grown under elevated CO (EC) often have a lowered grain nitrogen (N) and protein concentration along with an altered grain ionome. The mechanistic understanding on the impact of CO x N interactions on the grain ionome and the expression of genes regulating grain ionome is scarce in wheat. In the present study, the interactive effect of EC and N dosage on grain yield, grain protein, grain ionome, tissue nitrate, and the expression of genes contributing to grain ionome (TaNAM-B1 and TaYSL6) are described.

Analysis of NIA and GSNOR family genes and nitric oxide homeostasis in response to wheat-leaf rust interaction.

Nitric oxide (NO) modulates plant response to biotic and abiotic stresses by S-nitrosylation-mediated protein post-translational modification. Nitrate reductase (NR) and S-nitrosoglutathione reductase (GSNOR) enzymes are essential for NO synthesis and the maintenance of Nitric oxide/S-nitroso glutathione (NO/GSNO) homeostasis, respectively. S-nitrosoglutathione, formed by the S-nitrosylation reaction of NO with glutathione, plays a significant physiological role as the mobile reservoir of NO.

Role of protein phosphatases in the regulation of nitrogen nutrition in plants.

The reversible protein phosphorylation and dephosphorylation mediated by protein kinases and phosphatases regulate different biological processes and their response to environmental cues, including nitrogen (N) availability. Nitrate assimilation is under the strict control of phosphorylation-dephosphorylation mediated post-translational regulation. The protein phosphatase family with approximately 150 members in Arabidopsis and around 130 members in rice is a promising player in N uptake and assimilation pathways.

Interaction of elevated CO and form of nitrogen nutrition alters leaf abaxial and adaxial epidermal and stomatal anatomy of wheat seedlings.

Plant's stomatal physiology and anatomical features are highly plastic and are influenced by diverse environmental signals including the concentration of atmospheric CO and nutrient availability. Recent reports suggest that the form of nitrogen (N) is a determinant of plant growth and nutrient nitrogen use efficiency (NUE) under elevated CO (EC). Previously, we found that high nitrate availability resulted in early senescence, enhanced reactive oxygen species (ROS), and reactive nitrogen species (RNS) production and also that mixed nutrition of nitrate and ammonium ions were beneficial than sole nitrate nutrition in wheat.

Expression dynamics of genes encoding nitrate and ammonium assimilation enzymes in rice genotypes exposed to reproductive stage salinity stress.

Understanding the reproductive stage salinity stress tolerance is a key target for breeding stress tolerant rice genotypes. Nitrate and ammonium are equally important nitrogen forms utilized by rice. We evaluated nitrate and ammonium assimilation during reproductive stage in control and salinity (10dSm using NaCl) stressed rice plants.

Raffinose accumulation and preferential allocation of carbon ( C) to developing leaves impart salinity tolerance in sugar beet.

Sugar beet is a salt-tolerant crop that can be explored for crop production in degraded saline soils. Seeds of multigerm genotypes LKC-2006 (susceptible) and LKC-HB (tolerant) were grown in 150 mM NaCl, from germination to 60 days after sowing, to decipher the mechanism of salinity tolerance at the vegetative stage. The biomass of the root and leaf were maintained in the tolerant genotype, LKC-HB, under saline conditions.

Elevated CO differentially regulates root nitrate transporter kinetics in a genotype and nitrate dose-dependent manner.

The nitrogen (N) and protein concentration of wheat crop and grain often decline as a result of exposure of the crop to elevated CO (EC). In our earlier studies, it was found that the exacerbated production of nitric oxide (NO) represses the transcription of nitrate reductase (NR) and high affinity nitrate transporters (HATS) in EC grown wheat seedlings receiving high N. High N supply under EC also resulted in accumulation of reactive oxygen species (ROS), and reactive nitrogen species (RNS; NO and S- nitrosothiols) ensuing faster senescence and reduced N metabolite concentration in wheat.

Elevated CO alters tissue balance of nitrogen metabolism and downregulates nitrogen assimilation and signalling gene expression in wheat seedlings receiving high nitrate supply.

Tissue and canopy-level evidence suggests that elevated carbon dioxide (EC) inhibits shoot nitrate assimilation in plants and thereby affects nitrogen (N) and protein content of the economic produce. It is speculated that species or genotypes relying more on root nitrate assimilation can adapt better under EC due to the improved/steady supply of reductants required for nitrate assimilation. A study was conducted to examine the effect of EC on N assimilation and associated gene expression in wheat seedlings.

CO Elevation Accelerates Phenology and Alters Carbon/Nitrogen Metabolism ROS Abundance in Bread Wheat.

Wheat is an important staple food crop of the world and it accounts for 18-20% of human dietary protein. Recent reports suggest that CO elevation (CE) reduces grain protein and micronutrient content. In our earlier study, it was found that the enhanced production of nitric oxide (NO) and the concomitant decrease in transcript abundance as well as activity of nitrate reductase (NR) and high affinity nitrate transporters (HATS) resulted in CE-mediated decrease in N metabolites in wheat seedlings.

Genome wide analysis of NLP transcription factors reveals their role in nitrogen stress tolerance of rice.

The NIN-LIKE PROTEIN (NLP) family of transcription factors were identified as nitrate-responsive cis-element (NRE)-binding proteins, which function as transcriptional activators in the nitrate-regulated expression of downstream genes. This study was aimed at genome-wide analysis of NLP gene family in rice and the expression profiling of NLPs in response to nitrogen (N) supply and deficiency in rice genotypes with contrasting N use efficiency (NUE). Based on in silico analysis, 6 NLP genes (including alternative splice forms 11 NLPs) were identified from rice.

Characterization of Atypical Protein Tyrosine Kinase (PTK) Genes and Their Role in Abiotic Stress Response in Rice.

Tyrosine phosphorylation constitutes up to 5% of the total phophoproteome. However, only limited studies are available on protein tyrosine kinases (PTKs) that catalyze protein tyrosine phosphorylation in plants. In this study, domain analysis of the 27 annotated genes in rice genome led to the identification of 18 PTKs with tyrosine kinase domain.