Drought stress is an inevitable factor that disturbs the production of plants by altering
morphological, physiological, biochemical, and molecular functions. Breeding for drought tolerance
requires a complete understanding of the molecular factors controlling stress-responsive pathways.
The plant responds to drought stress by adopting four mechanisms: avoidance, escape, tolerance, and
recovery. Traditional plant-breeding tools have been employed to increase tolerance in cotton, but the
complexity of drought tolerance has limited the use of these breeding methods. The plant adopts
several key strategies against drought stress, such as activating the signaling network and activating
molecular factors. Cotton breeders have been engaged in elucidating the molecular mechanisms of
drought tolerance in cotton using significant molecular tools such as quantitative trait loci (QTL)
mapping, transcription factor (TFs) analysis, transcriptome analysis, genome-wide association studies
(GWAS), genetic engineering, and CRISPR/Cas9. Breeders have studied the functional description of
genes and the interacting pathways accountable for controlling drought tolerance in cotton. Hundreds
of genes/QTL have been identified, and many have been cloned for drought tolerance in cotton;
however, a complete understanding of these traits still needs more study. This review presents a
detailed overview of molecular tools, their application for improving drought tolerance in cotton,
and their prospects. This review will help future researchers to conduct further studies to develop
drought-tolerant cotton genotypes that can thrive under conditions of water scarcity.

Plants in their natural environment are constantly subjected to various abiotic and biotic stressors and, therefore, have developed several defense
mechanisms to maintain fitness. Stress responses are intricate and require various physiological, biochemical, and cellular changes in plants. The reaction
mechanisms in plants subjected to drought, salinity, or heat stress alone have been explained in numerous studies. However, the field conditions are significantly
different from the controlled laboratory conditions. In the field, crops or plants are simultaneously exposed to two or more abiotic and/or biotic stress
conditions, such as a combination of salinity and heat, drought and cold, or any of the abiotic stresses combined with pathogen infection. Studies have shown
that plants’ reactions to combinations of more than two stress factors are distinct and cannot be explicitly deduced from their responses to different stresses
when applied separately. Therefore, additional research is needed to understand the complete mechanism of plant responses to stress by analyzing data
between single stress and multiple stress responses. This review aims to provide an overview of current research on plant responses to a combination of
various stress conditions and their influence on the metabolic, transcriptional, and physiological characteristics of plants.

Due to environmental pollution, crop growth and productivity are threatened at different levels. Recapitulation
of changes in plant bodies due to water pollution and mitigating strategies reveal the need for pr´ecised actions to
save crop losses. The present study was carried out to estimate modulations in growth, mineral homeostasis, and
nutrient profile of fruits in Capsicum annum L. grown with three concentrations of wastewater (25, 50, 100%) and
two levels of silver nanoparticles (40 and 80 mg/L AgNPs). It has been reported that ion accumulation patterns
from wastewater clearly vary among crops. Our findings manifested that the application of AgNPs significantly
improved the mineral ions in different plant tissues, that ultimately helped to improve growth. Highest improvements
were recorded for root shoot P (316 and 197%) at T9 (80 mg/L AgNPs + normal water), while K
(273 and 262%), Mg (638 and 916%), and Ca (148 and 273%), at T11 (80 mg/L AgNPs + 50% Wastewater), in
comparison with control. Such reduction in elemental uptake that remain detrimental even at low concentrations
positively correlates with growth and nutrition of Capsicum plants. Another facet of our observation is dosedependent
improvement in nutritive attributes of fruits i.e., crude fibers, proteins, and carbohydrates by
AgNPs. T8 (40 mg/L AgNPs + 100% Wastewater), improved nutritional attributes such as P (55%), Mn (44%), Zn
(38%), Carbohydrates (62%), Crude fat (38%), and Fibers (49%) as compared to control. Application of silver
nanoparticles (AgNPs) combined with untreated wastewater (WW) reduced the hazards of contaminants in
plants. The finding of the current study suggested that AgNPs are a cost-efficient and environment friendly
material having the potential to mitigate harmful impacts of WW on plants.

This review delves into the mesmerizing technology of nano-agrochemicals, specifically
pesticides and herbicides, and their potential to aid in the achievement of UN SDG 17, which aims to
reduce hunger and poverty globally. The global market for conventional pesticides and herbicides is
expected to reach USD 82.9 billion by 2027, growing 2.7% annually, with North America, Europe, and
the Asia–Pacific region being the biggest markets. However, the extensive use of chemical pesticides
has proven adverse effects on human health as well as the ecosystem. Therefore, the efficacy, mechanisms,and
environmental impacts of conventional pesticides require sustainable alternatives for
effective pest management. Undoubtedly, nano-agrochemicals have the potential to completely transform
agriculture by increasing crop yields with reduced environmental contamination. The present
review discusses the effectiveness and environmental impact of nanopesticides as promising strategies
for sustainable agriculture. It provides a concise overview of green nano-agrochemical synthesis
and agricultural applications, and the efficacy of nano-agrochemicals against pests including insects
and weeds. Nano-agrochemical pesticides are investigated due to their unique size and exceptional
performance advantages over conventional ones. Here, we have focused on the environmental risks
and current state of nano-agrochemicals, emphasizing the need for further investigations. The review
also draws the attention of agriculturists and stakeholders to the current trends of nanomaterial use
in agriculture especially for reducing plant diseases and pests. A discussion of the pros and cons of
nano-agrochemicals is paramount for their application in sustainable agriculture.

The study of the DNA damage response in erythrocytes after exposure to volatile organic compounds (VOCs) can present evidence for its potential effect as genotoxic- biomarkers for environmental pollution. Although VOCs are dangerous pollutants, still little is known about hemotoxic, cytotoxic, and genotoxic effects of such pollutants on fish. We optimized an assay method for apoptosis and DNA damage in erythrocytes of adult tilapia fish after 15 days exposure to benzene (0.762 ng/L), toluene (26.614 ng/L), and xylene (89.403 ng/L). The highest level of apoptosis and DNA damage were recorded in benzene-exposed fish, as was the highest level of histopathological alterations in gills, liver, and kidney. The imbalance of the antioxidants profile explained the stress-case reported in exposed fish. These results suggest that hemotoxic, cytotoxic, genotoxic, and tissue damage were recorded after exposure to BTX in Oreochromis niloticus.

Microplastics (MPs) pollution is a newly emerging environmental issue. MPs can accumulate within animals and humans, which can pose a serious health threat. Petroleum-based polyethylene (PE) is one of the most popular plastics. Accordingly, its exposure rates have steadily increased over the years. This study aimed to analyze the effects of PE-MPs on the hematological system of albino rats and the epigenetic effect. Five groups of adult male eight-weeks-old rats received either distilled water, corn oil, 3.75 mg/kg PE-MPs, 15 mg/kg PE-MPs, or 60 mg/kg of PE-MPs, daily by oral gavage for 35 days. PE-MPs significantly increased the body weights of the rats and lipid peroxidation, with concomitant reduction of superoxide dismutase activity and depletion of reduced glutathione, thus adversely affecting oxidants/antioxidants balance. Moreover, PE-MPs increased the % of abnormal RBCs, irregular cells, tear drop cells, Schistocyte cells, and folded cells. The genotoxic effects on DNA were evident by increased DNA damage, confirmed by the comet assay, in addition to increased DNA methylation. The effects of PE-MPs have been shown to be dose correlated. In conclusion, this study provides evidence of dose-related PE-MPs-induced hematological, genotoxic, and epigenetic effects in mammals, and thus emphasizes the potentially hazardous health effects of environmental PE-MPs.

This study’s goal was to assess the catfish’s response to exposure to monoaromatic petroleum hydrocarbons (benzene, toluene, and xylene) and its recovery after exposure using oxidative stress, histopathological, and immunological changes as biomarkers. Four groups: one as control and other three exposed to benzene (0.762 ng/L), toluene (26.614 ng/L), and xylene (89.403 ng/L), respectively, for 30 days and then recovery period for 30 days. The levels of the cortisol, lipid peroxidation, and cytokines (IL-1β, IL-6) increased significantly (p < 0.05) after exposure to benzene and xylene compared to control. Superoxide dismutase (SOD), total antioxidant capacity (TAC), and acetylcholinstease (Ach) decreased significantly (p < 0.05) in fishes exposed to benzene only compared to control group. While glutathione-S-transferase (GST) did not show any change in different treatment groups compared to control group. The histopathological signs of liver exposed to benzene, toluene, and xylene displayed aggregation of melanomacrophages, congestion of sinusoids, vacuolar degeneration of hepatocytes, necrotic area with inflammatory cell infiltration, and thrombus of central vein. Kidney exposed to benzene, toluene, and xylene showed dilatation of Bowman’s space with atrophy of glomerular tuft, lyses of RBCs with mononuclear cell infiltration, multifocal area of hemopoietic tissue necrosis, organized thrombus with perivascular hemorrhage, focal inflammatory cellular reaction, renal tubular necrosis, and thrombus of blood vessels. Spleen exposed to benzene, toluene, and xylene showed hyperplasia of lymphoid follicles in white pulp in a mild degree. These lesions appeared to a mild degree or disappeared completely after recovery period to BTX except spleen. In conclusion, monocyclic aromatic hydrocarbons (BTX) are hazardous to fish and the toxicity level was as benzene > xylene > toluene even though after recovery period.

Pyrogallol is widely used in several industrial applications and can subsequently contaminate aquatic ecosystems. Here, we report for the first time the presence of pyrogallol in wastewater in Egypt. Currently, there is a complete lack of toxicity and carcinogenicity data for pyrogallol exposure in fish. To address this gap, both acute and sub-acute toxicity experiments were conducted to determine the toxicity of pyrogallol in catfish (Clarias gariepinus). Behavioral and morphological endpoints were evaluated, in addition to blood hematological endpoints, biochemical indices, electrolyte balance, and the erythron profile (poikilocytosis and nuclear abnormalities). In the acute toxicity assay, it was determined that the 96 h median-lethal concentration (96 h-LC₅₀) of pyrogallol for catfish was 40 mg/L. In sub-acute toxicity experiment, fish divided into four groups; Group 1 was the control group. Group 2 was exposed to 1 mg/L of pyrogallol, Group 3 was exposed to 5 mg/L of pyrogallol, and Group 4 was exposed to 10 mg/L of pyrogallol. Fish showed morphological changes such as erosion of the dorsal and caudal fins, skin ulcers, and discoloration following exposure to pyrogallol for 96 h. Exposure to 1, 5, or 10 mg/L pyrogallol caused a significant decrease in hematological indices, including red blood cells (RBCs), hemoglobin, hematocrit, white blood cells (WBC), thrombocytes, and large and small lymphocytes in a dose-dependent manner. Several biochemical parameters (creatinine, uric acid, liver enzymes, lactate dehydrogenase, and glucose) were altered in a concentration dependent manner with short term exposures to pyrogallol. Pyrogallol exposure also caused a significant concentration-dependent rise in the percentage of poikilocytosis and nuclear abnormalities of RBCs in catfish.

Marine environments contain plastic debris that potentially elicits adverse effects in aquatic organisms. In Egypt, microplastic pollution has been recognized as a significant issue; however risks associated with human consumption have not been fully elucidated. Here, we evaluated the frequency of occurrence, abundance, and distribution of microplastics (MPs) in marine fishes at market from the Mediterranean and Red seas in Egypt. Four fish markets distributed along the two seas (Hurghada and Suez in Red Sea) and (Port Said and Alexandria in Mediterranean Sea) were sampled in May 2021. In fish at markets, MPs were found throughout the gastrointestinal system (stomach and intestine) but were not detected in either muscle or liver. The body size (length and weight) of the market fish was positively correlated with and the concentration of MPs. The most frequent size of MPs observed in fish were between as >5000 μml (26%), followed by 500–1000 μm (25.8%), μm and 1000–5000 μm (22.7%). The highest MPs concentration was found in fish collected at the Hurghada site (4.16 items/individual). The most abundant polymers comprising plastic in marine fishes in Egypt in the Red Sea, the dominant Polymers of the MPs in fish was PE (59.4%), followed by PP (24.8%). while, In the Mediterranean Sea, the dominant Polymers of the MPs in fish was PP (48.5%), followed by PE (35.9%). We conclude that the size of the fish, its diet, and habitat are key factors related to MP bioaccumulation in marine fish species. We have improved our understanding of the risk MPs pose to fisheries and marine ecosystems by demonstrating their widespread presence there. Consequently, it is more important than ever to get plastics out of the sea.

Acute toxicity experiments were conducted to determine the lethal concentration 50 (LC50) of the Up Grade®46% SL for Oreochromis niloticus. Our results showed that the 96-h LC50 value of UPGR for O. niloticus was 29.16 mg L-1. To study hemato-biochemical effects, fish were exposed for 15 days to individual UPGR at 2.916 mg L-1, individual polyethylene microplastics (PE-MPs) at 10 mg L-1, and to their combinations UPGR+PE-MPs. UPGR exposure induced significant decrease in account of red blood cells (RBCs) and white blood cells (WBCs), platelets, monocytes, neutrophils, eosinophils, and the concentrations of hemoglobin (Hb), hematocrit (Hct), and mean corpuscular hemoglobin concentration (MCHC) than other treatments, compared to the control group. Sub-acute UPGR exposure significantly increase lymphocytes, mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH), compared to the control group. In conclusion, UPGR and PE-MPs displayed antagonistic toxic effects due to maybe the sorption of UPGR onto PE-MPs.