The Na+/H+ antiporter (NHX) gene subfamily is essential for plant adaptation to salt stress, contributing significantly to ion homeostasis. These antiporters play crucial function in various biological processes by regulating Na+ and H+ balance within plant cells. Yet their genomic features and roles of salicylic acid (SA) in regulating them, activating antioxidant defense mechanisms as well as nutrients acquisition under salt stress conditions remain largely unknown in many crop species. In this study, we identified the NHX gene family members of three Brassicaceae species including Brassica napus, Brassica rapa and Brassica oleracea and analyzed the expression patterns of NHX genes in response to salt stress and phytohormonal application (SA). Comprehensive computational analyses, encompassing domain and motif prediction, cellular localization, cis-regulatory elements (CREs), and post-translational modification (PTM) sites revealed distinct group-specific characteristics within the NHX gene family. These characteristics included chromosomal distribution, motif composition, exon count and protein length (amino acids). qRT-PCR analysis depicted significantly induced expression of NHXs, specifically, BnNHX7, BraNHX6 and BoNHX6 (4 ~ 6 folds) using different concentrations of NaCl (100 mM and 200 mM) and SA (10 mg/L and 20 mg/L) at different periods of time. SA induced antioxidant enzymatic activity (SOD 3 ~ 4 folds, POD 2 ~ 3 folds, CAT 1 ~ 2 folds and APX 11 ~ 12 folds), upregulated antioxidant genes (SOD, POD, APX, CAT) by 3 ~ 5 folds under salt stress, and improved nutrient acquisition in all respective Brassicaceae species. We have conducted the first molecular characterization of NHX genes in three Brassica species, revealing their dual role in salt stress adaptation through ion homeostasis and salicylic acid induced antioxidant regulation, thus identifying promising targets for crop improvement. Not applicable.

Phytosulfokine (PSK) is a tyrosine-sulfated pentapeptide found throughout the plant kingdom, playing key roles in plant growth, development, and responses to biotic and abiotic stresses. However, there is still a lack of a comprehensive analysis of the BnPSK gene family in Brassica napus. In this study, we conducted a genome-wide identification and characterized 19 BnPSK genes in oil seed plants, which are unevenly distributed across both sub-genomes (A and C). BnPSK proteins ranged from 77 to 99 amino acids (BnPSK3c and BnPSK3d) in length, all belonging to the PSK-α type and containing conserved PSK domains. Synteny analysis revealed that the expansion of the BnPSK gene family is primarily attributed to whole genome duplication, with homology to Arabidopsis thaliana PSK genes. A promoter region analysis identified cis-acting elements related to hormone and stress responses. An expression profile analysis showed that BnPSK genes are highly expressed in roots, leaves, petals, and pollens and are induced by both abiotic stresses and phytohormone application. Furthermore, RT-qPCR assay demonstrated that the expression levels of BnPSK4c, BnPSK5a, and BnPSK5b were significantly enhanced under drought stress (3~5-fold) both in plant roots and leaves following ABA application. Lastly, the application of ABA induced antioxidant activity including SOD, POD, CAT and APX (2~5-fold) and their corresponding genes (3~5-fold), and altered the ROS-signaling in rapeseed plants; also, strong evidence of mitigating drought stress was present. These findings establish a basis for further research into the role of the BnPSK gene family in oilseed plant tolerance against drought stress and underlying molecular mechanisms, offering valuable perspectives for developing novel peptides.

Plant glutamate receptor-like channels (GLRs) are homologs of animal ionotropic glutamate receptors. GLRs are critical in various plant biological functions, yet their genomic features and functions in disease resistance remain largely unknown in many crop species. Here, we report the results on a thorough genome-wide study of the GLR family in oilseed rape (Brassica napus) and their role in resistance to the fungal pathogen Sclerotinia sclerotiorum. A total of 61 GLRs were identified in oilseed rape. They comprised three groups, as in Arabidopsis thaliana. Detailed computational analyses, including prediction of domain and motifs, cellular localization, cis-acting elements, PTM sites, and amino acid ligands and their binding pockets in BnGLR proteins, unveiled a set of group-specific characteristics of the BnGLR family, which included chromosomal distribution, motif composition, intron number and size, and methylation sites. Functional dissection employing virus-induced gene silencing of BnGLRs in oilseed rape and Arabidopsis mutants of BnGLR homologs demonstrated that BnGLR35/AtGLR2.5 positively, while BnGLR12/AtGLR1.2 and BnGLR53/AtGLR3.2 negatively, regulated plant resistance to S. sclerotiorum, indicating that GLR genes were differentially involved in this resistance. Our findings reveal the complex involvement of GLRs in B. napus resistance to S. sclerotiorum and provide clues for further functional characterization of BnGLRs.

Cadmium (Cd) toxicity severely impedes plant growth and yield.

Evaluation of genetic and induced resistance phenomena in cucumbers against the root-knot nematode (Meloidogyne incognita) | Rana Muhammad Amir Gulzar, Ateeq Ur Rehman, Ummad ud din Umar, Muhammad Shahid, Muhammad Fahad Khan | Agricultural Journals

Cotton is one of the topmost fiber crops throughout the globe. During the last decade, abrupt changes in the climate resulted in drought, heat, and salinity. These stresses have seriously affected cotton production and significant losses all over the textile industry. The GhAGC kinase, a subfamily of AGC group and member of serine/threonine (Ser/Thr) protein kinases group and is highly conserved among eukaryotic organisms. The AGC kinases are compulsory elements of cell development, metabolic processes, and cell death in mammalian systems. The investigation of RNA editing sites within the organelle genomes of multicellular vascular plants, such as Gossypium hirsutum holds significant importance in understanding the regulation of gene expression at the post-transcriptional level. In present work, we characterized twenty-eight GhAGC genes in cotton and constructed phylogenetic tree using nine different species from the most primitive to the most recent. In sequence logos analyses, highly conserved amino acid residues were found in G. hirsutum, G. arboretum, G. raimondii and A. thaliana. The occurrence of cis-acting growth and stress-related elements in the promoter regions of GhAGCs highlight the significance of these factors in plant development and abiotic stress tolerance. Ka/Ks levels demonstrated that purifying selection pressure resulting from segmental events was applied to GhAGC with little functional divergence. We focused on identifying RNA editing sites in G. hirsutum organelles, specifically in the chloroplast and mitochondria, across all 28 AGC genes. The positive role of GhAGCs was explored by quantifying the expression in the plant tissues under abiotic stress. These findings help in understanding the role of GhAGC genes under abiotic stresses which may further be used in cotton breeding for the development of climate smart varieties in abruptly changing climate.