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Background: Nitrogen is one of the most important mineral nutrients for plants and is absorbed by the root system mainly in the inorganic form (NH + 4 and NO - 3 ). Plants absorb nitrogen as a food source for growth, biomass production, and development. Nitrogen is mainly absorbed as nitrate, which is the most common source of nitrogen available to higher plants. One of the unique features of nitrate transport is that NO - 3 is both a substrate for transport and an inducer of NO - 3 transport systems in genes and at physiological levels., Methods: In the present study, morphological and physiological traits (chlorophyll a/b, total chlorophyll, and carotenoid, antioxidant enzymes, and protein content), correlation between traits and gene expression, and principle component analysis of traits among five barley cultivars were measured in response to nitrogen deficiency (ND). The starved plants were transferred to a nutrient solution containing 0.2 mM and 2 mM NO - 3 up to 7 and 14 days after ND application and non-stressed conditions, respectively., Results: Gene expression analysis revealed that the 10 HvNRT2 genes were induced in the leaf and root tissues at 7 and 14 days after ND treatments in five barley cultivars. Expression of NRT2 genes by relative quantitative qRT-PCR analysis for 10 HvNRT2 genes were determined. Based on the gene expression, HvNRT2.1, HvNRT2.2, and HvNRT2.4 were strongly induced by NO - 3, peaking at 7 and 14 days after ND treatment. In contrast, the HvNRT2.4 showed only moderate induction in both leaves and roots. From our results, the Reyhan cultivar showed a significant increase in root fresh weight (RFW), protein content, and antioxidant enzyme activity in roots at 7 and 14 days after ND treatment as compared to the non-stressed condition. A highly positive correlation was observed between root catalase (CATr) and HvNRT2.2/2.5/2.6 leaves., Conclusion: The expression of HvNRT2.4 is increased during long-term nitrogen starvation, while the expression of HvNRT2.1 and HvNRT2.2 are transiently increased by ND. Based on physiological and morphological traits and molecular mechanisms, the Reyhan is considered a tolerant cultivar under ND condition., (© 2023. The Author(s).)

Background: The Plant U-box (PUB), ubiquitin ligase gene, has a highly conserved domain in potato. However, little information is available about U-box genes in potato (Solanum tuberosum). In this study, 62 U-box genes were detected in the potato genome using bioinformatics methods. Further, motif analysis, gene structure, gene expression, TFBS, and synteny analysis were performed on the U-box genes., Results: Based on in silico analysis, most of StU-boxs included a U-box domain; however, some of them lacked harbored domain the ARM, Pkinase_Tyr, and other domains. Based on their phylogenetic relationships, the StU-box family members were categorized into four classes. Analysis of transcription factor binding sites (TFBS) in the promoter region of StU-box genes revealed that StU-box genes had the highest and the lowest number of TFBS in MYB and CSD, respectively. Moreover, based on in silico and gene expression data, variable frequencies of TFBS in StU-box genes could indicate that these genes control different developmental stages and are involved in complex regulatory mechanisms. The number of exons in U-box genes ranged from one to sixteen. For most U-box genes, the exon-intron compositions and conserved motifs composition in most proteins in each group were similar. The intron-exon patterns and the composition of conserved motifs validated the U-box genes phylogenetic classification. Based on the results of genome distribution, StU-box genes were distributed unevenly on the 12 S. tuberosum chromosomes. The results showed that gene duplication may possess a significant role in genome expansion of S. tuberosum. Furthermore, genome evolution of S. tuberosum was surveyed using identification of orthologous and paralogous. We identified 40 orthologous gene pairs between S. tuberosum with Solanum lycopersicum, Oryza sativa, Triticum aestivum, Gossypium hirsutum, Zea maize, Coriaria mytifolia, and Arabidopsis thaliana as well as eight duplicated genes (paralogous) in S. tuberosum. StU-box 51 gene is one of the important gene among other StU-boxes in S. tuberosum under drought stress which was expressed in tuber and leaf under drought stress. Furthermore, StU-box 51 gene has the highest expression levels in four tissue-specific (stem, root, leaf, and tuber) in potato as well as it had the highest number of TFBS in promoter region. Based on our results, StU-box 51 can introduce to researcher to utilize in breeding program and genetic engineering in potato., Conclusions: The results of this survey will be useful for further investigation of the probable role and molecular mechanisms of U-box genes in response to different stresses., (© 2022. The Author(s).)

Background: Potato is one of the most important food crops worldwide, contributing key nutrients to the human diet. Plant hormones act as vital switchers in the regulation of various aspects of developmental and growth stages in potato. Due to the broad impacts of hormones on many developmental processes, their role in potato growth and developmental stages has been investigated. This review presents a description of hormonal basic pathways, various interconnections between hormonal network and reciprocal relationships, and clarification of molecular events underlying potato growth. In the last decade, new findings have emerged regarding their function during sprout development, vegetative growth, tuber initiation, tuber development, and maturation in potato. Hormones can control the regulation of various aspects of growth and development in potato, either individually or in combination with other hormones. The molecular characterization of interplay between cytokinins (CKs), abscisic acid (ABA), and auxin and/or gibberellins (GAs) during tuber formation requires further undertaking. Recently, new evidences regarding the relative functions of hormones during various stages and an intricate network of several hormones controlling potato tuber formation are emerging. Although some aspects of their functions are widely covered, remarkable breaks in our knowledge and insights yet exist in the regulation of hormonal networks and their interactions during different stages of growth and various aspects of tuber formation., Short Conclusion: The present review focuses on the relative roles of hormones during various developmental stages with a view to recognize their mechanisms of function in potato tuber development. For better insight, relevant evidences available on hormonal interaction during tuber development in other species are also described. We predict that the present review highlights some of the conceptual developments in the interplay of hormones and their associated downstream events influencing tuber formation.