Photochemical attributes determine the responses of plant species from different functional groups of ferruginous outcrops when grown in iron mining substrates.

Environments originating from banded iron formations, such as the canga , are important reference ecosystems for the recovery of degraded areas by mining. The objective of this work was to evaluate if the relationship between morphofunctional and photosynthetic attributes of native canga species from different functional group results in distinct responses when grown in iron mining tailings substrate. The experiment was carried out with species belonging to different functional groups: a widespread semi-deciduous tree-shrub, Myrcia splendens ; an endemic deciduous shrub, Jacaranda caroba ; and a nitrogen-fixing herbaceous species, Periandra mediterranea .

Rock n' Seeds: A database of seed functional traits and germination experiments from Brazilian rock outcrop vegetation.

Advancing functional ecology depends fundamentally on the availability of data on reproductive traits, including those from tropical plants, which have been historically underrepresented in global trait databases. Although some valuable databases have been created recently, they are mainly restricted to temperate areas and vegetative traits such as leaf and wood traits. Here, we present Rock n' Seeds, a database of seed functional traits and germination experiments from Brazilian rock outcrop vegetation, recognized as outstanding centers of diversity and endemism.

Revegetation of an area impacted by iron ore tailings: evaluating fertilization alternatives in native pioneer and secondary trees.

The iron ore tailings released into the Rio Doce basin after the Fundão dam collapse (Brazil), suppressed a large extent of local vegetation. The use of native species and appropriate fertilization techniques, with less economic and environmental impact, must be considered in the process for the restoration of affected areas by the tailings. For this purpose, six native tree species, pioneer (Anadenanthera colubrina, Bixa orellana, and Peltophorum dubium) and secondary (Cedrela fissilis, Handroanthus impetiginosus, and Handroanthus serratifolius), were selected.

Cultivating vegetables in tailings from the Fundão dam collapse: metal accumulation and risks to food safety.

A great amount of iron ore tailings from the collapse of the Fundão dam in Southeast Brazil was deposited in an extensive agricultural area. The presence of this material creates insecurity for the resumption of agricultural activities, especially the cultivation of vegetables, which can accumulate metals at potentially toxic levels. In this study, two vegetables consumed in the affected area, arugula and radish, were cultivated in tailings and in soil.

Integrative signaling of hydrogen peroxide and gibberellin on Zn-mediated alleviation of thermodormancy in sorghum seeds.

Increasing global temperatures could result in decreasing crop production by decreasing seed germination in the field due to thermodormancy acquisition. Certain metals appear to modulate seed thermodormancy, although the exact mechanisms of that effect have not yet been elucidated. We report here the effects of Zn on the thermodormancy of sorghum seeds.

Fertilization assures mineral nutrition but does not overcome the effects of Fe accumulation in plants grown in iron ore tailings.

The rupture of Fundão dam was the biggest environmental disaster of the worlds' mining industry, dumping tons of iron ore tailings into the environment. Studies have shown that the Fundão dam's tailings are poor in nutrients and have high Fe and Mn concentration. In this context, our objective was to evaluate the growth performance of two native tree species (Bowdichia virgilioides and Dictyoloma vandellianum) in two treatments: fertilized soil and fertilized tailings.

Does Samarco's spilled mud impair the growth of native trees of the Atlantic Rainforest?

The failure of the Fundão dam, the largest environmental disaster in the world's mining sector, was responsible for releasing millions of cubic meters of iron ore tailings into the environment. It affected thousands of hectares of the Atlantic Forest domain, one of the biodiversity hotspots for conservation. Considering the urgency to restore the flora of the affected area, we evaluated the effects that iron ore tailings from the Fundão reservoir have on the germination and initial growth of tree species native to the Atlantic Forest in the Rio Doce basin.

Does integrative effects of glyphosate, gibberellin and hydrogen peroxide ameliorate the deleterious effects of the herbicide on sorghum seed through its germination?

We investigated the interconnected roles of reactive oxygen species (ROS) generated upon seed exposure to glyphosate and/or gibberellic acid (GA), and the possible interaction between the herbicide and the plant hormone during germination of sorghum seeds. GA decreased antioxidant enzyme activity in embryos, and the over accumulation of hydrogen peroxide (HO) in 1000 mM GA-treated seeds resulted in the lowest germinability among treatments. The deleterious effects of glyphosate on germination rate, in contrast, were not related to HO accumulation, but to its interference with the mitochondrial electron transport chain.

Effects of Ciprofloxacin and Roundup on seed germination and root development of maize.

Their continuous release into the environment, associated with their inherent biological activity, has motivated investigations into the detrimental effects of antibiotics and herbicides in natural and agricultural ecosystems. In this study, the interactive effects of the antibiotic ciprofloxacin (Cipro) and the herbicide Roundup on seed germination and root development were investigated. Although both compounds act as inhibitors of the mitochondrial electron transport chain in seeds, neither Cipro nor Roundup disrupted germinability of maize seeds.

Ciprofloxacin vs. temperature: Antibiotic toxicity in the free-floating liverwort Ricciocarpus natans from a climate change perspective.

The physiological responses of the aquatic liverwort Ricciocarpus natans to ciprofloxacin (Cipro) exposure under different growth temperatures were investigated. Cipro appears to act as an inhibitor of mitochondrial Complex III by blocking the oxidation of quinol, resulting in the formation of hydrogen peroxide (HO). HO accumulation upon Cipro exposure is responsible for decreased photosynthesis in plants.

Responses of the nitrogen-fixing aquatic fern Azolla to water contaminated with ciprofloxacin: Impacts on biofertilization.

We investigated the ability of the aquatic fern Azolla to take up ciprofloxacin (Cipro), as well as the effects of that antibiotic on the N-fixing process in plants grown in medium deprived (-N) or provided (+N) with nitrogen (N). Azolla was seen to accumulate Cipro at concentrations greater than 160 μg g dry weight when cultivated in 3.05 mg Cipro l, indicating it as a candidate for Cipro recovery from water.

Hormonal profile and the role of cell expansion in the germination control of Cerrado biome palm seeds.

Little information is currently available concerning the mechanisms controlling palm seed germination. We compared the anatomical and physiological aspects of seeds of two neotropical palm species showing different levels of dormancy. The seeds of Attalea vitrivir and Butia capitata were evaluated for the endogenous contents of hormones (ABA, GAs, CKs, BRs, IAA, JA, SA and the ethylene precursor ACC) in their cotyledonary petiole and operculum (structures involved in germination control), the force necessary to displace the operculum, endo-β-mannanase activities, and embryo cell elongation.

Glyphosate Can Decrease Germination of Glyphosate-Resistant Soybeans.

We investigated the effects of different concentrations of glyphosate acid and one of its formulations (Roundup) on seed germination of two glyphosate-resistant (GR) and one non-GR variety of soybean. As expected, the herbicide affected the shikimate pathway in non-GR seeds but not in GR seeds. We observed that glyphosate can disturb the mitochondrial electron transport chain, leading to HO accumulation in soybean seeds, which was, in turn, related to lower seed germination.

Ciprofloxacin induces oxidative stress in duckweed (Lemna minor L.): Implications for energy metabolism and antibiotic-uptake ability.

We investigate the physiological responses and antibiotic-uptake capacity of Lemna minor exposed to ciprofloxacin. Ciprofloxacin (Cipro) induced toxic effects and hormesis in plants by significantly modifying photosynthesis and respiration pathways. A toxic effect was induced by a concentration ≥1.

Integrative effects of zinc and temperature on germination in Dimorphandra wilsonii rizz.: Implications of climate changes.

The integrative effects of zinc (Zn; 0 mg L , 75 mg L , 150 mg L , and 200 mg L ) and temperature (25 °C, 30 °C, and 35 °C) on seed germination of the threatened Brazilian species Dimorphandra wilsonii were evaluated. Zinc effects on seed germination were only observed at 30 °C and 35 °C. By stimulating respiration rates, rising temperatures accentuate hydrogen peroxide (H O ) formation in germinating seeds in the presence of Zn.

Effects of glyphosate acid and the glyphosate-commercial formulation (Roundup) on Dimorphandra wilsonii seed germination: Interference of seed respiratory metabolism.

Glyphosate-formulations are widely used in the Brazilian Cerrado (neotropical savanna) with little or no control, threatening population of the endangered species Dimorphandra wilsonii. We investigated the toxicity of different concentrations (0, 5, 25 and 50 mg l) of glyphosate acid and one of its formulations (Roundup) on seed germination in D. wilsonii.