ABA-dependent suberization and aquaporin activity in rice (Oryza sativa L.) root under different water potentials

Molecular and physiological characterizations of roots under drought stress in rice: A comprehensive review

Drought stress poses a major challenge to rice (Oryza sativa L.) production, significantly threatening global food security, especially in the context of climate change. Root architecture plays a key role in drought resistance, as rice plants require substantial water throughout their growth. The genetic diversity of rice root systems exhibits various growth patterns and adaptive traits that enable plants to endure water-deficient conditions. Harnessing this diversity to improve drought resilience demands a thorough understanding of critical root traits and adaptive mechanisms. This review explores rice roots' anatomical, physiological, and biochemical responses to drought, emphasizing important traits such as root architecture, xylem vessel modifications, root cortical aerenchyma (RCA), and water transport mechanisms. The role of biochemical regulators, including phytohormones, sugars, lipids, and reactive oxygen species (ROS), in root adaptation to drought is also explored. Additionally, the genetic and molecular pathways influencing root development under drought stress are discussed, with a focus on key genes and transcription factors (TFs) such as NAC, bZIP, AP2/ERF, and others that contribute to enhanced drought tolerance. Understanding these complex interactions is crucial for breeding drought-tolerant rice varieties, ultimately improving crop productivity under challenging environmental conditions.

XERICO as a target for engineering stress-resilient crops: Mechanisms, applications, and future directions

XERICO's capacity to enhance ABA-driven stress responses across diverse crops, its regulatory crosstalk with other hormonal pathways, and its compatibility with advanced genetic engineering tools highlight its central role in sustainable agriculture. Leveraging XERICO in crop improvement programs aligns with the urgent need to mitigate the impacts of climate-induced stress in agriculture, offering a pathway toward resilient and high-yielding crops. By enabling crops to withstand drought and other environmental stresses, XERICO-based biotechnological approaches hold transformative potential for global food security and environmental sustainability.

Recent insights into air space formation in plant shoots

An adequate supply of oxygen and carbon dioxide is essential for plant survival. Although plant cell walls are somewhat porous, their hydrated nature hampers gas diffusion. Furthermore, the cuticular wax coating the epidermal layer of aerial tissues strongly inhibits gas exchange. Because plants lack specialized systems that bind and transport gases, gases must be directly delivered to the target cells. This necessitates the establishment of effective gas transport pathways connecting stomata to the target cells. However, our understanding of this process remains fragmented. Recent studies have shed light on the mechanisms underlying air space formation in various model and non-model plant species. This review aims to consolidate these findings, to provide a comprehensive overview of our current understanding of air space formation, and to outline potential avenues for future research that will address remaining gaps in knowledge.

Physiological and transcriptomic evaluation of salt tolerance in Egyptian tomato landraces at the seedling stage

BACKGROUND

Tomato (Solanum lycopersicum) is an essential vegetable crop with a wonder fruit used as a good source for human food and health-promoting worldwide. Drought, water salinity, and soil salinity are the commonly known environmental factors that can limit the productivity of various crops between 30% and 50% of final yields. To counter these previous effects, scientists have focused their research on studying how tomato plants at different development stages behave under various saline environmental conditions.

RESULTS

In this study, we used bioinformatics analysis tools to identify the putative genes that are related to salt tolerance in tomatoes based on the percentage of similarity with salt tolerance genes from soybean, rice, wheat, barley, Arabidopsis and other plants. Within these, 254 genes were identified as putatively involved in salt tolerance in tomatoes. Furthermore, the putative tissue expression pattern of these genes under different times from various abiotic stresses was analyzed. Also, the Expression Cube tool was used to predict the putative expression of our target genes at various tissues in fruit development. Then we study the effect of various concentrations from Sodium chloride (NaCl) at different times on the behavior of two Egyptian tomato genotypes through estimate the physiological and metabolic changes such as; soluble sugars, glucose, fructose, total chlorophyll, chlorophyll a, and chlorophyll b contents. Moreover, the relative expression levels of salt tolerance genes in tomato SlAAO3, SlABCG22, SlABF3, SlALDH22A1, SlAPX2, SlAVP1, SlCYP175A, SlNHO1, SlP5CS, SlPIP1, SlTPS1 and SlUGE-1, were investigated in both tomato genotypes under various concentrations from salt tolerance in comparison with the wild-type plants.

CONCLUSIONS

At the end, bioinformatics tools help in the determination of novel genes in tomato that related with tomato plant response to salt stresses. Finally, the findings reported in this article are helpful to assess the two Egyptian tomato genotypes and for understanding the roles of candidate genes for tolerance to saline conditions. And offering insights into future using these genes for generating stress-resistant tomatoes and improving agricultural sustainability.

Role of Carrot (Daucus carota L.) Storage Roots in Drought Stress Adaptation: Hormonal Regulation and Metabolite Accumulation

Background: Drought stress has become one of the biggest concerns in threating the growth and yield of carrots (Daucus carota L.). Recent studies have shed light on the physiological and molecular metabolisms in response to drought in the carrot plant; however, tissue-specific responses and regulations are still not fully understood. Methods: To answer this curiosity, this study investigated the interplay among carrot tissues, such as leaves (L); storage roots (SRs); and lateral roots (LRs) under drought conditions. This study revealed that the SRs played a crucial role in an early perception by upregulating key genes, including DcNCED3 (ABA biosynthesis) and DcYUCCA6 (auxin biosynthesis). The abundance of osmolytes (proline; GABA) and carbohydrates (sucrose; glucose; fructose; mannitol; and inositol) was also significantly increased in each tissue. In particular, LRs accumulated high levels of these metabolites and promoted growth under drought conditions. Conclusions: Our findings suggest that the SR acts as a central regulator in the drought response of carrots by synthesizing ABA and auxin, which modulate the accumulation of metabolites and growth of LRs. This study provides new insights into the mechanisms of tissue-specific carrot responses to drought tolerance, emphasizing that the SR plays a key role in improving drought resistance.

Genome-Wide Identification of the Alfin-like Gene Family in Cotton (Gossypium hirsutum) and the GhAL19 Gene Negatively Regulated Drought and Salt Tolerance

Alfin-like (AL) is a small plant-specific gene family characterized by a PHD-finger-like structural domain at the C-terminus and a DUF3594 structural domain at the N-terminus, and these genes play prominent roles in plant development and abiotic stress response. In this study, we conducted genome-wide identification and analyzed the AL protein family in Gossypium hirsutum cv. NDM8 to assess their response to various abiotic stresses for the first time. A total of 26 AL genes were identified in NDM8 and classified into four groups based on a phylogenetic tree. Moreover, cis-acting element analysis revealed that multiple phytohormone response and abiotic stress response elements were highly prevalent in AL gene promoters. Further, we discovered that the GhAL19 gene could negatively regulate drought and salt stresses via physiological and biochemical changes, gene expression, and the VIGS assay. The study found there was a significant increase in POD and SOD activity, as well as a significant change in MDA in VIGS-NaCl and VIGS-PEG plants. Transcriptome analysis demonstrated that the expression levels of the ABA biosynthesis gene (GhNCED1), signaling genes (GhABI1, GhABI2, and GhABI5), responsive genes (GhCOR47, GhRD22, and GhERFs), and the stress-related marker gene GhLEA14 were regulated in VIGS lines under drought and NaCl treatment. In summary, GhAL19 as an AL TF may negatively regulate tolerance to drought and salt by regulating the antioxidant capacity and ABA-mediated pathway.

How plants sense and respond to osmotic stress

Drought is one of the most serious abiotic stresses to land plants. Plants sense and respond to drought stress to survive under water deficiency. Scientists have studied how plants sense drought stress, or osmotic stress caused by drought, ever since Charles Darwin, and gradually obtained clues about osmotic stress sensing and signaling in plants. Osmotic stress is a physical stimulus that triggers many physiological changes at the cellular level, including changes in turgor, cell wall stiffness and integrity, membrane tension, and cell fluid volume, and plants may sense some of these stimuli and trigger downstream responses. In this review, we emphasized water potential and movements in organisms, compared putative signal inputs in cell wall-containing and cell wall-free organisms, prospected how plants sense changes in turgor, membrane tension, and cell fluid volume under osmotic stress according to advances in plants, animals, yeasts, and bacteria, summarized multilevel biochemical and physiological signal outputs, such as plasma membrane nanodomain formation, membrane water permeability, root hydrotropism, root halotropism, Casparian strip and suberin lamellae, and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple osmosensors. We also discussed the core scientific questions, provided perspective about the future directions in this field, and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.