Water scarcity has affected much of Chile for the past 15 years, and Amelichloa caudata, a native species adapted to arid conditions, may offer a solution. The hypothesis of this study is that both acetylsalicylic acid (ASA) and biosolids (BSs) can positively influence plant growth under water stress. This study assessed the effects of ASA and BSs on edaphic, physiological, biochemical, and productive parameters of A. caudata under water scarcity conditions. Results showed that both treatments enhanced biomass production, plant height, leaf number, and canopy weight. ASA improved water retention, mitigating water stress effects and leading to biomass levels comparable to controls. In contrast, BSs did not show significant benefits and had the lowest biomass values under all conditions. The highest root dry weight was observed in water-restricted plants, while ASA-treated plants had lower malondialdehyde (MDA) levels, indicating reduced oxidative stress. However, BS treatment increased MDA levels, suggesting more severe oxidative damage. Despite improvements in water retention, high salt concentrations in BSs may limit their effectiveness and further research is required to optimize application rates.

Soil salinity is a major abiotic stress causing severe damage to plants. Thus, proper management approaches need to be developed to lessen the detrimental effect of salinity on crop growth and productivity. The objective of this study was to investigate the potential role of exogenous salicylic acid (SA) and potassium (K+) in mitigating the adverse effects of salt stress on tomato. Salt-stressed tomato seedlings Solanum lycopersicum L. cv. Agata were exposed to 0.1 mM SA and 5 mM K+, applied individually or simultaneously for two weeks. Obtained results showed that salt stress resulted in reduced growth rate associated with accumulation of Na+ ions, reduced K+ levels, lower K+/Na+ ratio, increased oxidative damage, reduced total chlorophyll and carbohydrate contents as well as disturbed proline accumulation and disrupted antioxidant system. Nevertheless, after SA and K+ supplementation, total chlorophyll, K+, total proteins, total carbohydrates, and proline contents as well as K+/Na+ ratio were significantly increased. Additionally, exogenous SA and K+ treatments enhanced the non-enzymatic and enzymatic antioxidant system and ensured better oxidative stress tolerance, as indicated by reduced H2O2 production and membrane lipid peroxidation, resulting in an increased membrane stability index. These effects were further enhanced by the simultaneous application of SA and K+, resulting in a better growth of salt-stressed tomato seedlings compared to single applications of these two growth regulators. Taken together, the results of the current study provide evidence that SA and K+ may interact to counteract the adverse effects of salt stress on the growth of tomato seedlings by improving osmotic and ionic homeostasis and upregulating the antioxidant defense system. Therefore, the simultaneous application of SA and K+ may be suggested as a promising approach for beneficial tomato growth at the seedling stage under salt-affected soil conditions.

Cadmium (Cd) stress constitutes a significant issue in agricultural soil, inflicts lethal damages to plants and posing a serious risk to public health as it enters the food chain. This review addresses the cause of Cd toxicity, its numerous forms and absorption mechanism via various transporters and their detrimental impacts on plants. At high level, Cd interacts with cellular molecules leading to overproduction of reactive oxygen species. Under Cd stress, plants naturally synthesize various compatible solutes to enhance the plant's stress tolerance and glycine betaine (GB) is one of such solutes which act as osmoprotectant in plants. The Cd causes oxidative damage to the cells, resulted in changes in morphological attributes, physiological processes etc. and it is indispensable to alleviate Cd toxicity. To mitigate the harmful impacts of Cd, plants adapt self-regulating tolerance mechanism by producing naturally occurring osmolytes and phytochelatins (PCs). Biosynthetic pathway of GB and GB-mediated tolerance mechanism via redox homeostasis, osmotic adjustment, and mechanism of compartmentalization of Cd into the vacuole, the role of genetic engineering in GB biosynthesis in crop plants through which plants can improve their stress tolerance have been discussed. Amalgamation of this strategy must be implemented in the market with synchronization of farmers into cooperatives. This will be beneficial for the improvement in soil, plant and human health alongwith the reduction of Cd toxicity in environment. Further, this strategy must be used by government and non-government agencies, which is the most economical approach to apply at the farmer level.

Soil salinization, a rising issue globally, is a negative effect of the ever-changing climate, which has drawn attention to, and exacerbated problems related to soil degradation and the decline in wetland rice (Oryza sativa L.) production, leading to an unstable national economy. The use of rhizosphere inhabiting microorganisms (plant growth-promoting rhizobacteria, PGPR) is a viable method for boosting agricultural production on saline soils and reduce salt stress in rice crops. The objective of this study was to support the development of rice under salt stress by using a consortium of bacterial strains. 'Pokkali' rice plants inoculated with single Bacillus tequilensis and B. aryabhattai isolates were compared with consortium and non-inoculated plants while salinity was increased and by irrigation with tap water (control), 30 mM (5 dS m(-1)) and 60 mM (10 dS m(-1)) NaCl. The present study exhibited that inoculation of a mixed inoculum at 5 dS m(-1) resulted in significantly higher dry weight of the shoots and roots of seedlings (9.29 and 1.24 g, respectively) which was due to the increased SPAD value, proline content (7.55 mu mol g(-1) FW), and antioxidant enzyme activity in the inoculated plants. The higher accumulation of osmoprotectants such as proline supported Na+ ion reduction and antioxidant enzymes such as ascorbate peroxidase and reduced polyphenol oxidase content protect against higher cellular damage, eventually leading to increase plant growth performance in saline soil. This study demonstrates some positive effects of the locally isolated salt tolerant consortium PGPR strains on the growth of rice plants under salt stress conditions.

Salinity is a widespread environmental stress that severely impedes plant growth and development from seed germination to harvest. Thus, the development of suitable management practices to minimize the deleterious effects of salt stress has become necessary. Among these methods, seed priming is considered as one of the potential physiological approaches to enhance seed germination in salt-affected soils. In the present research, we investigated the potentiality of gallic acid (1 mM) and hydrogen peroxide (2 mM) as priming agents to alleviate the salinity-inhibited germination of three faba bean cvs. (Najeh, Chourouk and Bachaar). The seeds were soaked in distilled water (hydropriming) or pretreated with gallic acid and hydrogen peroxide, individually and simultaneously, and then subjected to 150 mM NaCl-salinity. Our results revealed that mean germination time was significantly increased; whereas final germination percentage and germination index as well as dry weight and water content of the embryonic axes were considerably lowered by salt stress in the unprimed seeds of the three faba bean cvs. This decrease was associated with inhibited starch degradation and increased malondialdehyde contents. Our results also indicated that although all germination traits as well as starch metabolism were enhanced following gallic acid, hydrogen peroxide and hydropriming treatments to varying degrees, priming-mitigating effects were agent-dependent with regard to salt-induced oxidative damage, and osmoprotectant accumulation (proline and glycine betaine) as well as non-enzymatic (total polyphenols and flavonoids) and enzymatic (superoxide dismutase, catalase and guaiacol peroxide) antioxidant defense system. Contrarily to hydropriming treatment for which no obvious effects were observed, gallic acid and hydrogen peroxide priming significantly decreased the malondialdehyde content, increased proline and glycine betaine accumulation and enhanced the non-enzymatic as well as the enzymatic defense system to varying degrees for the three faba cvs. When compared to other treatments, simultaneous priming with gallic acid and hydrogen peroxide was more efficient in mitigating the adverse effects of salt stress on faba bean at the germination stage and may be, therefore, suggested as a potential strategy to overcome the salinity-mediated impairment of faba bean, particularly salt-sensitive genotypes, at the germination stage.

Plants exposed to adverse environmental conditions develop molecular mechanisms of adaptation and/or defense, the osmoprotectors, which function as compatible solutes and contribute to tolerance via prevention systems and protection against cellular damage caused by these abiotic stresses. This study aimed to identify and characterize the osmoprotectors proline and trehalose in cowpea plants cv. Carijo under controlled conditions of water-deficit and heat stress based on the IPCC scenario of 4.8 degrees C increase in temperature, evaluating their structure and function through computational methods, as well as gene expression by RT-qPCR. The experimental assays were carried out in growth chambers under controlled conditions with different levels of soil water availability, phenological phases and temperature regimes. From the in silico analyses, ten TPS genes and one P5CR gene were identified in Vigna unguiculata, and these were named according to their chromosomal location. The VuP5CR and VuTPS genes play roles in hormone pathway signaling and in the response to light and biotic and abiotic stresses. The genes P5CR (proline) and alpha TPS6 (trehalose) were induced with increased temperature and lower water availability in the vegetative phase of cowpeas. In addition, P5CR also showed induction with 50% water availability at high temperatures. In the pod filling phase, the P5CR and alpha TPS6 genes were repressed with water availability of 75%, while only the P5CR gene was induced when water availability was reduced to 25% under heat stress. P5CR and TPS6 genes were induced in cowpea cv. Carijo in response to associated abiotic stresses (water-deficit and high temperatures), which suggests their participation in the mechanisms of adaptation of the species in adverse environmental conditions.