•The effect of cover crops was evaluated in the field for 3 years.•Grasses used in medium to long term improve the physical quality of soil surface.•Legumes and grasses affect the physical attributes ...of the soil in different forms.•Multiple linear regression determined which variables are predominant in the S index.
Introducing cover crops during the rotation system and off-season can provide numerous benefits to the agricultural system, such as increased carbon stock and improved soil aeration. However, in the southern Amazon region, owing to the hot and humid climate, the cover crops used in agricultural production systems may not have the same beneficial effects in the Cerrado region. This makes it necessary to introduce and study new species of cover crops that have the potential to improve soil quality. The objective of this study was to compare, over time, the dry matter production of eight cover crops, and the effects of their cultivation on the physical attributes of the soil in the southern Amazon region. The experiment was conducted in a randomized complete block design with analyzes carried out over the 3 years of the experiment, in three replicates. The treatments were composed of eight cover crops: crotalaria (Crotalaria spectabilis), pigeon pea (Cajanus cajan), velvet-bean (Mucuna aterrima), buckwheat (Fagopyrum esculentum), ruziziensis grass (Urochloa ruziziensis), brizantha grass (Urochloa brizantha), pearl millet (Pennisetum glaucum), and finger millet (Eleusine coracana), and three evaluation years (2014, 2015, and 2016). The cover crops used in the experiment were selected based on their adaptation to the growing conditions and because they have characteristics of agricultural interest. In addition, cover crops chosen can be used in soybean-maize rotation systems, soybean-maize succession systems, as well as in agriculture-livestock integration systems through integrated cultivation systems. Using undisturbed soil samples, were analyzed the physical variables: porosity, mechanical resistance to root penetration and water retention. Pore size distribution was calculated using the first derivative of the equation of van Genuchten and S index was determined by the angle of inclination of the soil water retention curve inflection point. The results show that leguminous and grassy cover crops act differently under physical soil attributes over time. The results indicated that the cultivation of grasses, such as P. glaucum, increased the values of macroporosity (0.18 m3 m−3) in the 0.00–0.10 m layer at the end of the third year of cultivation, consequently, reduced the value of soil density (up to 1.14 Mg m−3) and mechanical resistance to root penetration (up to 1.77 MPa). The largest accumulation of dry matter was obtained with the cultivation of U. brizantha, which consequently proved to be the best cultivation option in the off-season in the southern Amazon region. The study provides a better understanding of the influence of cover crops on the physical attributes of the soil, which will contribute to making the correct recommendation of cover crops that can improve the physical properties of the soil in agricultural frontier regions in the southern Amazon rainforest.
We re-evaluate the Basel Committee on Banking Supervision’s (BCBS) proposed framework with the credit-to-GDP gap as an anchor indicator relative to the countercyclical capital buffer (CCB), and ...propose an alternative approach that focuses on credit-to-GDP growth. We estimate Bayesian structured time series models (STM) fully and recursively for 34 countries and evaluate whether these state components and related indicators can anticipate crises over the following three years. Using an early warning framework similar to the original BCBS one, we find leading indicators that outperform the credit-to-GDP gap in anticipating banking crises, with lower noise-to-signal (NS) ratios and similar sensitivities to threshold variation (assessed using receiver operational characteristics (ROC)). Moreover, the credit-to-GDP gap fails an exercise using limited information, suggesting that the 10% anchor on this indicator that was put forward by the BCBS can be misleading in countries with short credit series. Finally, we present an illustrative panel of CCB use with our leading indicators.
•Restricted Maximum Likelihood has a higher accuracy in Fields with higher anisotropy.•Kriging with Method of Moments has higher accuracy in areas with lower anisotropy.•Spatial variability in soil ...chemical fertility used in Precision Agriculture must be modeled.•Directional effects in geospatial data must be considered in variogram modeling.•Synthetic data with variable levels of trend and anisotropy were simulated.
Precision Agriculture (PA) commonly uses interpolation to generate maps for site-specific management. Semivariogram modeling with kriging interpolation considerers several parameters such as trend and anisotropy, which require proper estimation to return reliable maps. Often present in agricultural fields, these directional effects can also account for machine traffic and crop/soil management. Despite modeling trend and anisotropy being desirable for creating soil fertility maps, these effects are often disregarded during semivariogram modeling. Hence, this study evaluates whether semivariogram modeling considering anisotropy and trend influences the improvement of maps used in precision agriculture. Predicted performance and trends identified in the data when modeling anisotropy were evaluated considering two sampling grid densities, using the method of moments (MoM) and restricted maximum likelihood (REML) to estimate semivariogram parameters. Different levels of trend and anisotropy were tested on four types of virtual fields with 100 repetitions, and two experimental fields. Data were processed in an automated manner for virtual field generation, sampling extraction, semivariogram modeling, kriging, and cross-validation. Metrics were then subjected to bootstrapping and the differences were compared using confidence intervals. Results indicate that modeling directional effects improved the accuracy of kriging-generated maps. REML resulted in the best variability estimation in strong anisotropy, whereas MoM was more efficient in fields with weaker anisotropy. Modeling anisotropy was particularly useful in experimental fields, where trend was considered a function of spatial covariates. Consequently, semivariogram modeling must consider both directional effects to provide accurate soil fertility maps for precision agriculture.
Piper umbellatum L. leaves, commonly found in the Amazon, Cerrado and Atlantic rain forest regions of Brazil, are widely used as a traditional medicine to treat gastrointestinal disorders and ...inflammation, among others diseases. Also, previous scientific studies demonstrated that P. umbellatum has gastroprotective and anti-inflammatory activity.
To investigate the phytochemical profiles and the intestinal anti-inflammatory effect of the hydroethanolic extract of P. umbellatum (HEPu) leaf on ulcerative colitis in rats.
In this study, the chemical composition of HEPu was analyzed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography coupled to mass spectrometry (LC/MS). Also, this work studied the effects of HEPu on ulcerative colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS, 30 mg/mL in 20% ethanol) by intrarectal administration in rats. Simultaneously, animals were pre-treated orally with HEPu (30, 100 and 300 mg/kg), mesalazine (500 mg/kg), or vehicle. At the end of the experimental period, clinical signs of ulcerative colitis were evaluated by determination of weight loss, gross appearance, ulcer area and histological changes. Reduced glutathione (GSH), lipoperoxides (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD), myeloperoxidase (MPO) and catalase (CAT) activities were determined in colon tissues. Also, pro-inflammatory mediators such as tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL- 1β) were quantified by immunoassay on the surface of fluorescent-coded magnetic beads (Luminex MagPix System).
GC-MS analysis showed the presence of 17 different phytochemical compounds in the HEPu. LC/MS analyses revealed the presence of compounds in HEPu as protocatechuic acid, ferulic acid, kaempferol, rosmarinic acid, apigenin and ursolic acid. Treatment with HEPu significantly ameliorated weight loss, macroscopic damage, ulcerated area and histopathological changes such as sub-mucosal edema, cell infiltration, ulceration and necrosis (p < 0.001). Furthermore, HEPu (30, 100, and 300 mg/kg, p.o) inhibited the levels of oxidative parameters, such as MPO (49%, 53%, and 62%, p < 0.001), NO (20%, 19%, 22%, p < 0.01), and MDA (75%, 83%, 70%, p < 0.001), whereas increased the antioxidant activities such as SOD (208%, 192%, 64%, p < 0.001), GSH (94%, 75%, 49%, p < 0.01), and CAT (92%, 69%, 108%, p < 0.01). The extract also inhibited the pro-inflammatory cytokines TNF-α (81%, 85%, 85%, p < 0.001) and IL-1β (95%, 79%, 89%, p < 0.001) levels.
Together, these results revealed that P. umbellatum L. is a promising source of metabolites to be used in the treatment of inflammatory bowel disease.
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In the present paper the anti-diabetic effects of stem-bark extract (ethanol 70%) of
Vatairea macrocarpa, a traditional diabetes mellitus treatment widely used in Brazil, are reported. The extract ...was administered orally at a dose of 250 or 500
mg/kg, for 22 days, to normal and streptozotocin-diabetic rats. In extract treated (500
mg/kg) diabetic rats serum and urinary glucose, urinary urea, food and fluid intake were decreased, while body weight gain was increased, all of which indicate an improvement in diabetic state (
p
<
0.05). No effects of the extract were observed in non-diabetic rats. In extract treated (500
mg/kg) diabetic group HOMA-R (homeostasis model for assessment of insulin resistance) was lower at the end of 22 days, as compared to diabetic non treated control group. Insulin was the reference substance used in the experiments. In an oral glucose tolerance test, the time to reach maximal glycemia was greater in diabetic 500
mg/kg treated group than in control group. These anti-diabetic effects could be related to an improved insulin resistance, although a possible effect on pancreatic B-cell function cannot be excluded. Thus, our data of sub-chronic experiments suggest that long-term use of
V. macrocarpa stem-bark extract may be helpful in treating diabetic conditions.
Fridericia chica, Bignoniaceae, is a tropical tree-creeper used as a traditional remedy for a number of diseases, highlighting inflammation. Our objective was to corroborate the popular ...anti-inflammatory use of the hydroethanolic extract from the leaves (HEFc) and of its isolated 4′,6,7-trihydroxy-5-methoxyflavone (5-O-methylscutellarein) 1, described here for the first time. Quantitative analysis indicated 8.77 ± 0.23 mg/g of this compound in the extract. Neither HEFc nor 1 was cytotoxic in vitro. In LPS-induced peritonitis in mice, oral pre-treatment with HEFc or 1 led to decreased leukocyte migration to the peritoneal cavity and a reduction in the concentrations of pro-inflammatory cytokines (TNFα and IL-1β). Also, the anti-inflammatory cytokine IL-10 was enhanced following treatment with 1. Overall, these results validate the traditional use of Fridericia chica as anti-inflammatory, and indicate that the compound 5-O-methylscutellarein may participate in this effect.
Divergence studies are essential for the conservation of genetic resources and guidance in genetic improvement programs. This study aimed to assess the phenotypic dispersion of half-sib progenies ...using Gower's algorithm and the non-metric multidimensional scaling analysis based on qualitative and quantitative traits. Twenty-two half-sib progenies of African mahogany (Khaya senegalensis) were evaluated in a randomized block design with 22 treatments (progenies/origin), with 30 replications and one plant per plot, totaling 660 plants. The total tree height (cm), diameter at soil level (cm), chlorophyll A and B, presence of bifurcation, presence of lateral branches, stem tortuosity, and the phytosanitary and nutritional status according to a rating scale were evaluated. Data analysis was performed at the progeny mean level for the quantitative traits and the modal value was used for the qualitative traits. The technique used presented the distance between the progenies of K. senegalensis in a graphical form. The dispersion of the progenies in the graph is indicative that there is phenotypic variation in the progeny test, allowing to select individuals with characteristics of interest to improve mahogany for Piauí. Gower's algorithm applied to mixed data and non-metric multidimensional scaling are efficient methods to describe phenotypic similarities between progenies.
Sphenodesme involucrata var. paniculata (C. B. Clarke) Munir is native as well as endemic to South India. Its leaves are used in folklore medicine to treat pain and rheumatism.
This study was aimed ...to investigate the chemical characterization, anti-nociceptive and mode of action underlying the anti-inflammatory effects of methanol extract of S. involucrata leaves (MESi).
Phytoconstituents of MESi was analyzed using colorimetric and liquid chromatography–mass spectrometry (LC-MS) methods, and the oral acute toxicity was evaluated in mice up to 2000 mg/kg. The anti-nociceptive effect was evaluated in hot plate and writhing tests; whereas the anti-inflammatory effect was investigated using carrageenan, cotton pellet and lipopolysaccharide (LPS)-induced peritonitis models at doses of 100, 200 and 400 mg/kg. Additionally nitric oxide (NO) and inflammatory cytokines levels were also evaluated.
MESi exhibited the high content of phenolics and flavonoids as well as compounds like austricine, benzylglucosinolate, gossypin, justicidin B and cirsimarin were detected in LC-MS. In the acute toxicity study, oral administration of MESi did not cause any toxic effect and mortality up to 2000 mg/kg body weight in mice. In the anti-nociceptive tests, MESi augmented the latency period at higher dose (400 mg/kg), on the other hand attenuated writhings at the dose of 400 mg/kg by 87.87% (p < 0.001). In the carrageenan induced paw oedema MESi significantly inhibited the oedema formation at dose 400 mg/kg by 32.1%; besides, anti-inflammatory effect was registered in the cotton pellets-induced inflammation model at doses 200 and 400 mg/kg by 27.09% (p < 0.001) and 35.47% (p < 0.001) respectively. On the other hand, MESi appreciably reduced leukocyte, neutrophils infiltration, nitric oxide, TNF-α and IL-1β levels and increased the IL-10 level in the (LPS)-induced peritonitis model.
The results conclude that MESi has no acute toxic effect and it demonstrated potent anti-nociceptive and anti-inflammatory activities. Its anti-nociceptive activities are probably mediated through peripheral and central mechanisms. The anti-inflammatory effect of MESi involved the inhibition of neutrophils migration and the modulation of Th1 and Th2 cytokines, besides the attenuation of production of PGE2 and NO. LC-MS analysis revealed the predominant presence of the austricine, benzylglucosinolate, gossypin, justicidin B and cirsimarin compounds, which are possibly involved in the anti-nociceptive and anti-inflammatory effects of MESi. The current study provided supportive evidence for the folklore use of S. involucrata in the treatment of pain and inflammatory conditions.
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Ellagic acid (EA), a plant-derived polyphenol, exhibits antioxidant, anti-inflammatory, and gastroprotective effects. Its gastroprotective mechanisms have not been fully elucidated nor have its ...effects on chronic ulcer previously been described. Toward these ends, the antiulcer activities of EA were evaluated in acute (ethanol and indomethacin) and chronic (acetic acid) ulcer models in Wistar rats. In this study, oral administration of EA significantly prevented the gastric ulceration caused by ethanol, indomethacin, and acetic acid treatments. Its gastroprotective mechanism in ethanol-induced ulcer were partly due to intensification in the endogenous production of nitric oxide, an antioxidant effect by replenishing depletion of endogenous nonprotein sulfhydryls and attenuation of tumor necrosis factor-α increase, whereas in indomethacin ulcer, it is partly due to a reduction in the plasma level of leukotriene B4. In acetic acid ulcer, promotion of ulcer-healing effects was partly due to attenuation of the elevated levels of the inflammatory cytokines TNF-α, interferon-γ, and interleukins-4 and -6. These findings suggest that ellagic acid exerts its antiulcer activity by strengthening the defensive factors and attenuating the offensive factors.
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