Soil contamination with heavy metals is a major problem worldwide, due to the increasing impact mainly caused by anthropogenic activities. This research evaluated the phytoremediation capacity of, Lolium perenne for heavy metals such as cadmium (Cd2+) and mercury (Hg2+), and the effects of these metals on morphology, biomass production, and the changes on gene expression. Seeds of L. perenne were exposed to six concentrations of Cd2+ and Hg2+ in the range of 0 to 25 mg L−1, and two mixtures of Cd2+–Hg2. The Non-Observed Effect Level (NOEL) was established with dose response curves and the expression of specific genes was evaluated applying a commercially available quantitative reverse transcription (RT-qPCR) assay. There was no significant effect when exposing the seeds to Hg2+, for Cd2+ the maximum concentration was established in 0.1 mg L−1, and for the two concentrations of mixtures, there was a negative effect. An increase of expression of genes that regulate antioxidant activity and stress was found when the plant was exposed to heavy metals. Given the high tolerance to metals analyzed that was reflected both, the development of the plant and in its molecular response, these results highlight that L. perenne is a plant with phytoremediator potential.

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The purpose of this study was to evaluate the capability of Aspergillus tubingensis and Talaromyces islandicus to solubilize inorganic phosphorus sources, their activity under abiotic stress, and the enhancement of P availability in soils and plant growth. The P-solubilizing capability and acidification mechanism of the strains were assessed in vitro using tricalcium phosphate and rock phosphate. Independent assays were conducted with rock phosphate under NaCl and fungicides carbendazim, chlorothalonil, and propamocarb hydrochloride using a factorial design. Thereafter, the effects of fungal inoculations in rock phosphate-amended soil and P nutrition of Zea mays were assessed in a greenhouse experiment. Both fungi solubilized P in vitro via acidification through the exudation of acetic, citric, lactic, malic, quinic, and succinic acids. The P-solubilizing efficiency of A. tubingensis was maintained above 97.5% under 0.5 to 3.0% NaCl, up to 28.7% in the treatment with carbendazim, up to 5.3% with chlorothalonil, and above 96.5% with propamocarb hydrochloride; while T. islandicus efficiency decreased to 45.2% in a NaCl concentration-dependent trend, and maintained it above 80% in the fungicide treatments. The inoculation with A. tubingensis increased the available P in the amended soil by up to 65% after 30 days and resulted in 87% higher foliar P content, 111% greater plant height, and 25% greater dry weight of maize shoots. Similarly, T. islandicus contributed to these parameters in 55, 67, 90, and 17%, respectively. These findings suggest their potential as qualified phosphorus solubilizing microorganisms to develop novel and sustainable approaches for P fertilization in agriculture.

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Coastal zones sustain extensive biodiversity, support key processes for ocean dynamics, and influence the balance of the global environment. They also provide resources and services to communities, determine their culture, and are the basis for their economic growth. Cartagena Bay in the Colombian Caribbean is the place of the establishment of one of the country’s main cities, which has a great historical and tourist attraction, and it is also the location of the main commercial port and a great variety of industries. Historically, it has been affected by several environmental impacts and intense pollution. This situation has gained the attention of different researchers, so herein is presented a literature review with a systematic approach using RStudio’s bibliometrix on the presence of pollutants and the impact on biodiversity in recent decades, providing a critical analysis of the state of Cartagena Bay and its future needs to ensure its recovery and conservation. In addition, the socioeconomic dynamics related to the environmental state of Cartagena Bay are presented from the framework drivers, pressures, status, impacts, and responses (DPSIR). The update and critical understanding of the sources, fate, and effects of pollution are important not only for the knowledge of the status of this singular ecosystem but also to encourage future research and entrench evidence to support decision makers’ actions. This review highlights that several pollutants that have been detected exceeding sediment quality guidelines, like As, Cd, Hg, and PAH, are also reported to bioaccumulate and cause damage throughout the trophic levels of the coastal environment. In addition, the potential use of sentinel species and biomarkers for their monitoring is discussed. Finally, the factors that cause pollution and threaten the state of the bay continue to exert pressure and impact; thus, there is a call for the further monitoring of this ecosystem and the strengthening of policies and regulations.