Biology subjects

Jangir, N.

Publications and source records attributed to Jangir, N..

4 recordsLinked to original sources

bioRxiv2026

Genome-wide association study and transcriptomics reveal the genetic architecture of alkalinity tolerance in Arabidopsis thaliana

Alkalinity stress significantly restricts global plant productivity, yet the genetic basis for plant tolerance remains largely uncharacterized. In this study, a genome-wide association study was performed using 218 diverse natural Arabidopsis thaliana ecotypes to identify the top 73 SNPs associated with alkalinity tolerance, measured by relative root length in hydroponic growth media containing NaHCO3 at pH 8.0. Prominent association peaks were localized near genes involved in lipid metabolism (GGL20), protein degradation (AT3G17570), and vesicle-mediated protein sorting (VPS13B and AT5G57210). Expression level and protein polymorphisms in these genes were associated with alkalinity tolerance. T-DNA mutants of GGL20, AT3G17570, and the chromatin-modifying gene AFR1 showed alkaline hypersensitivity, reduced root length, iron content, and rosette size, and elevated hydrogen peroxide. Conversely, mutants of the DNA repair gene ETG1 exhibited greater tolerance than wild type in hydroponics, solid media, and soil assays, confirming their role in alkalinity tolerance. Transcriptome and network analyses revealed that alkalinity responses significantly overlap with iron deficiency pathways, identifying hub genes involved in ribosome assembly and translation control. These findings provide a comprehensive map of the genetic and transcriptional landscape of alkalinity adaptation and offer promising candidate genes for engineering crops resilient to alkaline soil conditions.

plant biology↗

bioRxiv2025

A desert endophyte, Priestia megaterium SI1-IITJ, improves fluoride stress tolerance by reducing fluoride content of plant tissues and perturbing salt tolerance and defense genes of Arabidopsis thaliana

We isolated a fluoride (F-)-resistant bacterium, Priestia megaterium SI1-IITJ, from thse internal root tissues of several Thar Desert plants, Aerva javanica, Cyperus conglomeratus, Senna tora, and Tephrosia purpurea, tolerating up to 100 mM NaF. The root endophytic behavior of the isolate was confirmed by scanning electron microscopy. SI1-IITJ possesses plant growth-promoting properties, including auxin production (19.8 g mL-1), phosphate solubilization (index 3.64), ACC deaminase (0.54 mmol -ketobutyrate mL-1) and nitrate reductase (0.65 mol mL-1 nitrite) activities, revealed by biochemical tests and whole genome sequencing. SI1-IITJ extrudes F- from the cell, possibly through an F- efflux transporter, CrcB, identified in its genome. Significant growth improvements were observed in Arabidopsis thaliana under F- stress in hydroponics and soil culture upon coculture with SI1-IITJ, which improved the chlorophyll content by 1.6%, total nitrogen by 30.4%, and reduced reactive oxygen species by 48.9% and F- content by 63.9% in plant tissues. A differential gene expression analysis of A. thaliana by transcriptome sequencing indicated an unperturbed F- exporter, AtFEX1, but up-regulation of 55 genes regulating root meristem growth, cell wall modification, chlorophyll biosynthesis, Fe homeostasis, and high salt- and abiotic stress-responsive genes. On the other hand, 103 genes were down-regulated, suppressing systemic acquired resistance, plant defense, and H2O2 production. In conclusion, our results provide genomic insights into the mechanisms of F- toxicity alleviation and plant growth enhancement by a desert PGPR, highlighting Priestia megaterium SI1-IITJ as a potential biofertilizer for mitigating F- stress in plants.

plant biology↗

bioRxiv2024

Foliar application of nano urea results in higher biomass, chlorophyll, and nitrogen content than equimolar bulk urea through differential gene regulation in Arabidopsis thaliana

Indian Farmers Fertilizer Cooperative (IFFCO)s liquid nano urea formulation (NUF) was applied to one-month-old Arabidopsis thaliana plants grown in vermiculite as a 0.4% foliar spray twice at an interval of 10 days and compared with sprays of equimolar bulk urea. NUF resulted in a 51 {+/-} 14.9% increase in biomass, 29.5 {+/-} 9.1% in chlorophyll, 8.4 {+/-} 3.1% in nitrogen, and 4.5 {+/-} 0.3% in amino acid content of the leaves, compared to bulk urea. NUFs zeta potential of -54.7 mV and particle size of [~=]27.7 nm, measured by dynamic light scattering and transmission electron microscopy, make it suitable for stomatal uptake. We conducted a differential gene expression analysis by mRNA sequencing to understand the molecular basis of the phenotypic gains under NUF rather than urea. NUF resulted in significantly higher expression levels of 211 genes (log2fold-change > 0.5, FDR < 0.05) involved in the biosynthesis of carbohydrates, amino acids, nucleotides, lipids, phytohormones, and secondary metabolites, cell wall biosynthesis and modification, growth and developmental processes, cell cycle, and stress response than bulk urea. On the other hand, 1,286 genes (log2fold-change < -0.5) involved in cell death, abscission, senescence, nitrogen transport and metabolism, and biotic stress response showed lower expression levels upon NUF application than bulk urea. Our results suggest that although NUF foliar spray suppresses nitrogen uptake genes, possibly due to nitrogen excess, it enhances growth by up-regulating the synthesis of essential biomolecules and growth-promoting genes, compared to bulk urea.

plant biology↗

bioRxiv2023

Peribacillus frigoritolerans T7-IITJ, a potential biofertilizer, induces plant growth-promotinggenes of Arabidopsis thaliana

This study aimed to isolate plant growth and drought tolerance-promoting bacteria from the nutrient- poor rhizosphere soil of several plant species from the Thar desert and unravel their molecular mechanisms of plant growth promotion, to develop effective biofertilizers for arid agriculture. Among our isolates of Thar desert rhizobacteria, Enterobacter cloacae C1P-IITJ, Kalamiella piersonii J4-IITJ, and Peribacillus frigoritolerans T7-IITJ, significantly enhanced root and shoot growth in the model plant Arabidopsis thaliana under PEG-induced drought stress in the lab. Whole genome sequencing and biochemical analyses of the non-pathogenic bacterium T7-IITJ revealed its plant growth-promoting traits, viz., solubilization of phosphate, iron, and nitrate and production of exopolysaccharides and auxin. Transcriptome analysis of Arabidopsis thaliana inoculated with T7-IITJ and exposure to drought revealed the induction of plant genes for photosynthesis, auxin and jasmonate signaling, nutrient mining and sequestration, redox homeostasis, and secondary metabolite biosynthesis pathways related to beneficial bacteria-plant interaction, but repression of many stress-responsive genes. Biochemical analyses indicated enhanced proline, chlorophyll, iron, phosphorous, and nitrogen content and reduced reactive oxygen species in plant tissues due to T7-IITJ inoculation. This bacterium could also improve the germination and seedling growth of Tephrosia purpurea, Triticum aestivum, and Setaria italica under drought. Additionally, T7-IITJ inhibited the growth of two plant pathogenic fungi, Rhizoctonia solani, and Fusarium oxysporum. These results suggest P. frigoritolerans T7-IITJ is a potent biofertilizer which can regulate plant genes promoting growth and drought tolerance.

plant biology↗