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Plants that produce allelopathic compounds against weeds have emerged as a potential solution for the development of ecologically correct bioherbicides. Talinum triangulare is noteworthy in this regard, as its phytochemical composition encompasses flavonoids, alkaloids and other metabolites that can be used to develop inhibitory weed growth solutions. Lactuca sativa (lettuce) has been widely applied as a bioindicator species for bioherbicides and several chemicals, animal waste, water and soil quality, and atmospheric contamination, among others. In this context, this study aimed to assess the potential allelopathic effect of aqueous T. triangulare extracts on the development of L. sativa seedlings. A completely randomized design employing a 2x4 factorial scheme (shoot and root extracts) x the concentration of each extract (0, 2.5, 5, 7.5%) was applied, comprising four replications. Lactuca sativa seeds were sown on germitest papers soaked with the extracts in a germination chamber at 20°C. Physiological seed evaluations comprising the germination test, where normal and abnormal seedlings are counted on the seventh day after sowing, first normal seedling counts on the fourth day after sowing, and seedling and root length measurements. At the end of the germination test, L. sativa seedlings were separated for morphoanatomical characterizations and chlorophyll a fluorescence analyses. The T. triangulare extracts significantly influenced L. sativa root growth, with shoot extract exposure leading to more abnormal plants and lower root lengths at increasing concentrations and compared to the root extract. Root extract exposure led to evident cellular changes and lower non-photochemical quenching and unregulated dissipation quantum yields at a 5% exposure dose compared to shoot extract exposure. These findings suggest that both aqueous T. triangulare root and shoot extracts from 5% exposure doses exhibit high potential as bioherbicides, acting directly on plant structure, anatomy, quality, size and physiology.

Glyphosate is a herbicide commonly used in agriculture for weed control. Current agricultural production demands vast amounts of this product, which are applied by ground or aerial spraying. The concomitant aerial currents promote glyphosate drift to vegetated or urban areas. In this context, we hypothesized that the lichens, Parmotrema tinctorum and Usnea barbata, could be sensitive to the action of glyphosate and therefore be used to bio-indicate the presence of this herbicide in areas affected by drift. Since living organisms respond in different ways to the action of herbicides, our interest was also to indicate biological markers responsive to the action of glyphosate, through concentrations and exposure times of the thallus, besides identifying the most sensitive species. We evaluated the effect of different concentrations (0.0, 4.8, 9.6, and 19.2 mg L-1) and exposure times (24, 48, and 72 hours) to glyphosate on the morphoanatomy, photobiont vitality, photosynthetic efficiency, and oxidative metabolism of the thalli. We found that the lichens, P. tinctorum and U. barbata, respond to glyphosate stress, with prospects for use in the biomonitoring of pollutant dispersal from plantation areas. When using P. tinctorum as a bioindicator, lichen morphoanatomy, photobiont vitality, and photosynthetic pigment concentration were efficient biomarkers for the effect of concentration and exposure time. For U. barbata, the lichenic morphoanatomy and the activity of SOD and APX enzymes were essential tools to indicate the herbicide action. Parmotrema tinctotum, however, was characterized as more sensitive in bio-indicating the presence of this herbicide to diagnose the air quality in urban areas or vegetation sectors adjacent to agricultural environments.

The objective of this study was to verify the physiological behavior and development of maize plants under hydric deficit inoculated with the AMF Rhizophagus clarus and Claroideoglomus etunicatum and the commercial inoculant ROOTELLA BR in nonsterilized soil as a strategy to mitigate the effects of drought in the crop. Corn seeds were grown and inoculated with R. clarus, C. etunicatum and the commercial inoculant ROOTELLA BR separately at sowing. The plants were grown in a greenhouse and submitted to water deficit in stage V3, keeping the pots at 20% field capacity for 10 days. The first analyses were performed, followed by reirrigation for 2 days, and the analyses were performed again. The experiment was a double factorial, with 2 water treatments (irrigated and water deficit) × 4 inoculation treatments (control, ROOTELLA BR, R. clarus, C. etunicatum) × 5 replicates per treatment, totaling 40 vessels. The results indicate that the plants were able to recover favorably according to the physiological data presented. It is noted that in inoculated plants, there was no damage to the photosynthetic apparatus. These data demonstrate that AMF contribute greatly to better plant recovery after a dry period and a new irrigation period. Inoculation with AMF favors postwater stress recovery in plants., (© 2023. The Author(s).)

Water deficit (WD) combined with high temperature (HT) is the major factor limiting agriculture worldwide, and it is predicted to become worse according to the current climate change scenario. It is thus important to understand how current cultivated crops respond to these stress conditions. Here we investigated how four soybean cultivars respond to WD and HT isolated or in combination at metabolic, physiological, and anatomical levels. The WD + HT increased the level of stress in soybean plants when compared to plants under well-watered (WW), WD, or HT conditions. WD + HT exacerbates the increases in ascorbate peroxidase activity, which was associated with the greater photosynthetic rate in two cultivars under WD + HT. The metabolic responses to WD + HT diverge substantially from plants under WW, WD, or HT conditions. Myo-inositol and maltose were identified as WD + HT biomarkers and were connected to subnetworks composed of catalase, amino acids, and both root and leaf osmotic potentials. Correlation-based network analyses highlight that the network heterogeneity increased and a higher integration among metabolic, physiological, and morphological nodes is observed under stress conditions. Beyond unveiling biochemical and metabolic WD + HT biomarkers, our results collectively highlight that the mechanisms behind the acclimation to WD + HT cannot be understood by investigating WD or HT stress separately., (© 2022. The Author(s).)

Biodiversity in the Brazilian Cerrado biome has been declining sharply with the continued expansion of agriculture and the excessive use of herbicides. Thus, the aim of this study was to evaluate the morphophysiological and biochemical responses in Dipteryx alata plants to various doses of the herbicide 2,4-D. Specific biomarkers that characterize the phytoindicator potential of this species were determined. Gas exchange, chlorophyll a fluorescence, photosynthetic pigments, and the activities of antioxidant enzymes and cellulase were performed after 24, 96 and/or 396 hours after 2,4-D application (HAA). The herbicide caused higher antioxidant enzymatic activity 24 HAA and damage to the photosynthetic machinery after 96 HAA. Reduction in gas exchange, chlorophyll content, and photochemical traits were observed. Increased respiratory rates, non-photochemical quenching, and carotenoid concentrations in 2,4-D-treated plants were important mechanisms in the defense against the excess energy absorbed. Furthermore, the absence of leaf symptoms suggested tolerance of D. alata to 2,4-D. Nevertheless, changes in the photosynthetic and biochemical metabolism of D. alata are useful as early indicators of herbicide contamination, especially in the absence of visual symptoms. These results are important for early monitoring of plants in conserved areas and for preventing damage to sensitive species.

Little is known about the role of light intensity in modulating plant responses to stress due to water deficit (WD). Thus, the objective of this study was to determine the WD and contrasting irradiance effects on the physiology, anatomy, and grain yield of soybean plants. The experimental design was a randomized block in a growth chamber and a 2 × 2 factorial treatment arrangement: 90% (well-watered, WW) and 40% (WD) of soil field capacities (FC); and 750 (medium irradiance, MI) and 1500 (higher irradiance, HI) μmol (photons) m -2  s -1 irradiance. The WD caused a lower photosynthetic rate - as well as observed in the light curve and in the relative parameters, such as apparent quantum efficiency -, less investment in shoot biomass and pollen grain germination, resulting in lower grain yield. However, there was an increase in non-photochemical energy dissipation, a higher concentration of total soluble sugars, proline, and malondialdehyde. The WD + MI-soybean plants developed thicker spongy parenchyma (related to higher mesophilic conductance of CO 2 ). In the WW + HI condition the palisade parenchyma was thicker, conferring maintenance of photosynthetic efficiency. In addition, there was an increase in the activity of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase antioxidant enzymes in leaves due to HI, regardless of FC. This induced higher energy expenditure, reflected in the reduction of the number of leaf and branches, leaf area, dry mass of leaves and stem in the WW + HI. Interestingly, these strategies of osmotic adjustment, photoprotection, and antioxidant defenses act together in the WD + HI., (© 2021 Scandinavian Plant Physiology Society.)

Fungicides are widely used to control diseases in soybean crops. We hypothesized that fungicides applied to healthy soybean plants compromise the plant's physiology, affect the reproductive process and reduce crop productivity. We aimed to evaluate the photosynthetic process, pollen grain viability and yield components of soybean plants exposed to three commercial fungicides. The experiment was performed twice using soybean cultivar SYN 1378C, disease-free plants, with four treatments: i) control treatment (without any fungicide application); ii) cyproconazole 150 g L -1  + difenoconazole 250 g L -1 (CPZ + DFZ; 250 mL ha -1 ; without adjuvant); iii) azoxystrobin 300 g Kg -1  + benzovindiflupyr 150 g Kg -1 (AZB + BZP; 200 g ha -1 ; Nimbus® adjuvant (Syngenta)); and iv) propiconazole 250 g L -1  + difenoconazole 250 g L -1 (PPZ + DFZ; 150 mL ha -1 ; without adjuvant) in both soybean pre-bloom (V8) and bloom (R1) developmental stages. The experimental design was randomized blocks with four replicates. Phytotoxicity, gas exchange and chlorophyll a fluorescence traits, pollen grain viability, pollen grain germination, flower abortion and soybean production components were evaluated. The fungicides did not affect the physiological traits, pollen grain germination and crop yield., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The expansion of land use for agricultural interests and the excessive use of herbicides are among the causes of biodiversity losses in the Brazilian Cerrado biome. Therefore, we aimed to test the hypothesis that Dipteryx alata Vogel, a common species in this biome, is sensitive to nicosulfuron because of its high phytotoxicity. We evaluated physiological, biochemical and morphological responses in D. alata plants exposed to increasing doses of the herbicide. Young plants were transplanted to 10 L pots containing substrate composed of soil and sand (2:1) after fertilization. After an acclimation period, the following doses of nicosulfuron were applied: 0 (control), 6, 12, 24, 48, and 60 g a.e. ha -1 . The experiment was conducted in a randomized block design factorial scheme with six doses of nicosulfuron, three evaluation times, and five replicates per treatment. The effects of the herbicide were assessed by measuring gas exchange, chlorophyll a fluorescence, photosynthetic pigments, membrane permeability, antioxidant enzymes and acetolactate synthase. Nicosulfuron altered the photosynthetic machinery and enzymatic metabolism of D. alata. Reductions in physiological traits, increased catalase and ascorbate peroxidase activities, enhanced malondialdehyde concentrations rate of electrolyte leakage and decreased acetolactate synthase activity in response to nicosulfuron all suggest that D. alata is sensitive to this herbicide.

Soybean is the most widely grown oilseed in the world. It is an important source of protein and oil which are derived from its seeds. Drought stress is a major constraint to soybean yields. Finding alternative methods to mitigate the water stress for soybean is useful to maintain adequate crop yields. The aim of this study was to evaluate the morpho-physiological, biochemical and metabolic changes in soybean plants in two ontogenetic stages, under exposure to water deficit and treatment with zinc sulphate (ZS), potassium phosphite (PP) or hydrogen sulphide (HS). We carried out two independent experiments in the V4 and R1 development stages consisting of the following treatments: well-watered control (WW, 100% maximum water holding capacity, MWHC), water deficit (WD, 50% MWHC), PP + WW, PP + WD, HS + WW, HS + WD, ZS + WW and ZS + WD. The experimental design consisted of randomized blocks with eight treatments with five replicates. Morphological, physiological and metabolic analyses were performed 8 days after the start of the treatments for both experiments. We identified two tolerance mechanisms acting in response to compound application during water stress: the first involved the upregulation of antioxidant enzyme activity and the second involved the accumulation of soluble sugars, free amino acids and proline to facilitate osmotic adjustment. Both mechanisms are related to the maintenance of the photosynthetic parameters and cell membrane integrity. This report suggests the potential agricultural use of these compounds to mitigate drought effects in soybean plants., (© 2019 Scandinavian Plant Physiology Society.)

There are a substantial amount of suppliers for roller mills in the market, but there is a lack of scientific evidence of a roller mill's capacity to improve particle size reduction/distribution or homogenization. In this concise paper, we evaluate the use a roller mill in the final steps of compounding semisolid dosage forms. We performed three simple tests to verify these claims: 1) particle size evaluation through dynamic light scattering and scanning electron microscopy techniques, 2) content uniformity through high-performance liquid chromatography technique, and 3) cross contamination through a cleaning validation method. Dynamic light scattering and scanning electron microscopy techniques of benzoyl peroxide 5% (gel) and testosterone 1% (cream) showed a significant reduction on particle diameter. Content uniformity testing of creams containing progesterone 5%, estradiol 0.1%, and estriol 0.4% showed better homogeneity when using the roller mill. Finally, the proposed cleaning procedure decreased the presence of the compounded preparation to a "none-detection" level after the procedure. This suggests that the roller mill used does, in fact, play a role in the final aspect and quality of pharmaceutical semisolid dosage forms., (Copyright© by International Journal of Pharmaceutical Compounding, Inc.)

Crambe abyssinica is widely cultivated in the off-season in the Midwest region of Brazil with great potential for biodeisel production. Low precipitation is characteristic of this region, which can drastically affect the productivity of C. abyssinica. Signaling molecules, such as nitric oxide (NO), can potentially alleviate the effects of water stress on plants. Here we test whether nitric oxide, applied by donor sodium nitroprusside (SNP), can alleviate the occurrence of water deficit damages in Crambe plants and maintain physiological and biochemical processes. Crambe plants were sprayed with three doses of SNP (0, 75, and 150 μM) and were submitted to two water levels (100% and 50% of the maximum water holding capacity). After 32 and 136 h, leaves were analyzed to evaluate the concentration of NO, water relations, gas exchange, chlorophyll a fluorescence, chloroplastidic pigments, proline, malondialdehyde, hydrogen peroxide, superoxide anions, and the antioxidant enzymes activity. Application of SNP allowed the maintenance of gas exchange, chlorophyll fluorescence parameters, and activities of antioxidant enzymes in plants exposed to water deficit, as well as increased the concentration of NO, proline, chloroplastidic pigments and osmotic potential. The application of SNP also decreased the concentration of malondialdehyde and reactive oxygen species in plants submitted to water deficit. Thus, the application of SNP prevented the occurrence of symptoms of water deficit in Crambe plants, maintaining the physiological and biochemical responses at reference levels, even under stress conditions., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

In Brazil, the expansion of agricultural activity and the associated indiscriminate use of herbicides such as glyphosate is directly related to the loss of biodiversity in the Cerrado. The identification of plant species as bioindicators of herbicide action, especially species native to the area, can help in monitoring the impacts of xenobiotics in the remaining Cerrado. Thus, this study was designed to evaluate the possible use of the native Cerrado species Pouteria torta as a bioindicator of glyphosate action via changes in physiological performance. At 16 months after sowing, the effect of glyphosate was evaluated by applying the following doses: 0 (control), 25, 50, 100, 200, 400, 800, and 1200 g a.e. ha-1. In response to glyphosate, P. torta exhibited reductions in photosynthesis and chloroplastid pigment content, as well as accumulation of shikimic acid and the occurrence of chlorosis and necrosis. These changes demonstrate the high sensitivity of P. torta to glyphosate and its potential for use as a bioindicator of this herbicide.

The wide use of the herbicide diuron has compromised surrounding uncultivated areas, resulting in acute and/or chronic damage to non-target plants. Thus, the aim of this research was to evaluate physiological and morphoanatomical responses in Bauhinia variegata L. plants to different doses of diuron. Seedlings of 90-day-old B. variegata were transplanted into 10liter pots. After an acclimation period (about 30 days), treatments consisting of different diuron doses were applied: 0 (control), 400, 800, 1600, and 2400g ai ha -1 . The experiment was conducted in a randomized block design in a 5×5 factorial scheme with five doses of diuron five evaluation times, and five replicates per treatment. Anatomical and physiological injuries were observed in leaves of Bauhina variegata 10h after diuron application. Disruption of waxes was observed on both sides of the leaves of plants exposed since the lowest dose. Plasmolysis in cells were observed in treated leaves; more severe damage was observed in plants exposed to higher doses, resulting in rupture of epidermis. The diuron herbicide also caused gradual reduction in the gas exchange and chlorophyll fluorescence variables. Among the morphoanatomical and physiological variables analyzed, the non-invasive ones (e.g., ETR, Y II , and F v /F m ) may be used as biomarkers of diuron action in association with visible symptoms. In addition, changes in leaf blade waxes and chlorophyll parenchyma damage may also be considered additional leaf biomarkers of diuron herbicide action., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The use of fungicides in maize has been more frequent due to an increase in the incidence of diseases and also the possible physiological benefits that some of these products may cause. However, some of these products (e.g., strobilurins and triazoles) may interfere with physiological processes and the formation of reproductive organs. Therefore, the effect of these products on plants at different developmental stages needs to be better understood to reduce losses and maximize production. The effect of the fungicide pyraclostrobin+epoxiconazole (P+E) was evaluated at different growth stages in meiosis, pollen grain viability and germination, physiology, and production of maize plants in the absence of disease. An experiment was carried out with the hybrid DKB390 PROII and the application of pyraclostrobin+epoxiconazole at the recommended dose and an untreated control at 3 different timings (S1 - V10; S2 - V14; S3 - R1) with 5 replications. Gas exchange, chlorophyll fluorescence, pollen viability and germination, as well as the hundred-grain weight were evaluated. Anthers were collected from plants of S1 for cytogenetic analysis. The fungicide pyraclostrobin+epoxiconazole reduced the viability of pollen grains (1.4%), but this was not enough to reduce production. Moreover, no differences were observed in any of the other parameters analyzed, suggesting that P+E at the recommended dose and the tested stages does not cause toxic effects., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Context: Familial nonmedullary thyroid carcinoma (FNMTC) accounts for approximately 5% of all thyroid tumors. Genetic mapping studies have identified four different chromosomal regions predisposing to FNMTC: fPTC/PRN (1p13.2-1q22), NMTC1 (2q21), MNG1 (14q32), and TCO (19p13.2)., Objective: Our objective was to map the gene predisposing to familial thyroid epithelial neoplasia in a large Portuguese family., Methods and Results: The clinical screening of a Portuguese family identified 11 members affected with benign thyroid lesions and five affected with thyroid carcinomas. Linkage analysis excluded the involvement of the fPTC/PRN, NMTC1, MNG1, and TCO loci. To map the gene predisposing to thyroid epithelial neoplasia in this family, a genome-wide linkage analysis was conducted, using DNA samples from 17 family members and high-density single-nucleotide polymorphism arrays. A genome-wide significant evidence of linkage, to a single region on chromosome 8p23.1-p22 was obtained, with a maximum parametric haplotype-based LOD score of 4.41 (theta=0.00). Linkage analysis with microsatellite markers confirmed linkage to 8q23.1-p22, and recombination events delimited the minimal region to a 7.46-Mb span. Seventeen suggestive candidate genes located in the minimal region were excluded as susceptibility genes by mutational analysis. Allelic losses in the 8p23.1-p22 region were absent in seven thyroid tumors from family members, suggesting that the inactivation of a putative tumor suppressor gene may have occurred through other mechanisms., Conclusions: Our results present evidence for the existence of a novel familial thyroid epithelial neoplasia susceptibility locus on chromosome 8p23.1-p22, providing the basis for the identification of a gene for this disease.

Linkage analysis has identified four familial non-medullary thyroid carcinoma (FNMTC) susceptibility loci: fPTC/PRN (1p13.2-1q22), NMTC1 (2q21), MNG1 (14q32) and TCO (19p13.2). To date, there is no evidence for the involvement of genes from the RAS/RAF signalling pathway in FNMTC. The aim of our study was to evaluate the role of the four susceptibility loci, and RAS/RAF signalling pathway genes, in FNMTC. In total, 8 FNMTC families, and 27 thyroid lesions from family members (22 papillary thyroid carcinomas (PTCs): 11 classic, 10 of the follicular variant and 1 of the mixed variant; 4 follicular thyroid adenomas (FTAs) and 1 nodular goitre (NG)), were evaluated for the involvement of the four susceptibility regions, using linkage and loss of heterozygosity (LOH) analyses. BRAF and H-, N- and K-RAS mutations were also screened in the 27 lesions and patients. Linkage analysis in seven informative families showed no evidence for the involvement of any of the four candidate regions, supporting a genetic heterogeneity for FNMTC. Twenty tumours (74%), of which 18 were PTCs, showed no LOH at the four susceptibility loci. The remaining seven tumours (four PTCs, two FTAs and one NG) showed variable patterns of LOH. Fourteen tumours (52%) had somatic mutations: BRAF-V600E mutation was observed in 9 out of the 22 PTCs (41%); and H-RAS and N-RAS mutations were detected in 5 out of the 22 PTCs (23%). Our data suggest that the four candidate regions are not frequently involved in FNMTC and that the somatic activation of BRAF and RAS plays a role in FNMTC tumourigenesis.