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Recurrent selection is an effective and well‐known breeding method recommended for quantitative traits. However, the method has not been applied so far for traits typically controlled by numerous major loci, which is the case of resistance to anthracnose in common bean (Phaseolus vulgaris L.). In this study, we report the effectiveness of a recurrent selection program in developing common bean progenies with resistance to multiple races of Colletotrichum lindemuthianum, the causal agent of anthracnose in this crop. A total of 10 common bean lines, with distinct and complementary resistance profiles to races 65, 73, 81, and 89 of C. lindemuthianum, were intercrossed to establish a base population (Cycle 0). From Cycle 0, five iterative cycles of recombination, inoculation, and selection were carried out. Our results demonstrate that this recurrent selection approach can effectively combine resistance in common bean to different isolates from multiple races of C. lindemuthianum. A progressive increase in the number of progenies resistant to a higher number of C. lindemuthianum isolates was observed over the selection cycles. The genetic gain from CI to CV was 38.75% when the progenies were evaluated against a mixture of isolates from the four races of the pathogen. The reliance on specific genes makes race‐specific anthracnose resistance in common bean vulnerable to breakdown. By allowing optimal combinations of different anthracnose resistance genes, this dynamic recurrent selection approach is an attractive option for the development of common bean cultivars with increased stability and durability for anthracnose resistance. [ABSTRACT FROM AUTHOR]

Background Children with congenital Zika syndrome (CZS) have severe damage to the peripheral and central nervous system (CNS), greatly increasing the risk of death. However, there is no information on the sequence of the underlying, intermediate, immediate, and contributing causes of deaths among these children. The aims of this study are describe the sequence of events leading to death of children with CZS up to 36 months of age and their probability of dying from a given cause, 2015 to 2018. Methods and findings In a population-based study, we linked administrative data on live births, deaths, and cases of children with CZS from the SINASC (Live Birth Information System), the SIM (Mortality Information System), and the RESP (Public Health Event Records), respectively. Confirmed and probable cases of CZS were those that met the criteria established by the Brazilian Ministry of Health. The information on causes of death was collected from death certificates (DCs) using the World Health Organization (WHO) DC template. We estimated proportional mortality (PM%) among children with CZS and among children with non-Zika CNS congenital anomalies (CA) by 36 months of age and proportional mortality ratio by cause (PMRc). A total of 403 children with confirmed and probable CZS who died up to 36 months of age were included in the study; 81.9% were younger than 12 months of age. Multiple congenital malformations not classified elsewhere, and septicemia unspecified, with 18 (PM = 4.5%) and 17 (PM = 4.2%) deaths, respectively, were the most attested underlying causes of death. Unspecified septicemia (29 deaths and PM = 11.2%) and newborn respiratory failure (40 deaths and PM = 12.1%) were, respectively, the predominant intermediate and immediate causes of death. Fetuses and newborns affected by the mother's infectious and parasitic diseases, unspecified cerebral palsy, and unspecified severe protein-caloric malnutrition were the underlying causes with the greatest probability of death in children with CZS (PMRc from 10.0 to 17.0) when compared to the group born with non-Zika CNS anomalies. Among the intermediate and immediate causes of death, pneumonitis due to food or vomiting and unspecified seizures (PMRc = 9.5, each) and unspecified bronchopneumonia (PMRc = 5.0) were notable. As contributing causes, fetus and newborn affected by the mother's infectious and parasitic diseases (PMRc = 7.3), unspecified cerebral palsy, and newborn seizures (PMRc = 4.5, each) were more likely to lead to death in children with CZS than in the comparison group. The main limitations of this study were the use of a secondary database without additional clinical information and potential misclassification of cases and controls. Conclusion The sequence of causes and circumstances involved in the deaths of the children with CZS highlights the greater vulnerability of these children to infectious and respiratory conditions compared to children with abnormalities of the CNS not related to Zika., Author(s): Maria da Conceição N. Costa 1,2, Luciana Lobato Cardim 1, Cynthia A. Moore 3, Eliene dos Santos de Jesus 2,4, Rita Carvalho-Sauer 2,5, Mauricio L. Barreto 1,2, Laura C. [...]

The objective of this study was to optimize the enzymatic pretreatment process of extracting menthol, a major component of the essential oil stored in the trichomes of fresh leaves of Mentha arvensis, by the action of the crude enzymatic extract previously produced by the Aspergillus niger fungus cultivated in cactus pear. Under the experimental conditions of 42 °C, 141 min and 58 mL of enzyme in 442 mL of water, there was an increase of 186.63% in the hydrodistillation yield, which represents an acceptable positive deviation of 12.54% compared to the predicted value of the model obtained by experimental design. Trichome rupture can be confirmed by scanning electron microscopy (SEM) and the chemical structure of the obtained menthol was not modified according to gas chromatography and infrared spectroscopy. The enzymatic pretreatment applied before the hydrodistillation step was successful and proves the potential of the association of biotechnological techniques with a physicochemical process. [ABSTRACT FROM AUTHOR]

We determined the size-mass relationships for two populations of the freshwater crab Trichodactylus fluviatilis Latreille, 1828 in the Atlantic Forest along the southeastern coast of Brazil. Different mathematical models (linear, exponential, and power) and body variables (carapace length (CL) and width (CW)) were used to determine the best relationships to estimate the biomass of males, females, and all individuals sampled. The values of the body variables and biomasses did not differ between the sexes or the populations studied. Considering data for all individuals and for males only, the best relationships to estimate the biomass of T. fluviatilis were determined using the power model and CW in the Macuco population and the power model and CL in Mestre Álvaro (model selection using small-sample corrected Akaike's Information Criteria). The best relationships in females were calculated using the linear and power models and CW in the two streams. The slopes of the power model equations determined by both body variables did not differ between the sexes in either stream, but differences were observed when all individuals of the populations were considered. The results support the use of carapace length and width as predictors of the biomass of T. fluviatilis and the population-specificity of size-mass relationships, which requires the determination of one specific equation for each population studied. The biomass estimation of T. fluviatilis through size-mass relationships contributes to the evaluation of the role of these macroconsumers in the detritus-based food webs of Atlantic Forest streams. [ABSTRACT FROM AUTHOR]

We evaluated the effect of leaves of native and exotic tree species on the feeding activity and performance of the larvae of Triplectides gracilis, a typical caddisfly shredder in Atlantic Forest streams. Leaves of four native species that differ in chemistry and toughness (Hoffmannia dusenii, Miconia chartacea, Myrcia lineata and Styrax pohlii) and the exotic Eucalyptus globulus were used to determine food preferences and rates of consumption, production of fine particulate organic matter (FPOM), growth and survival of shredders. We hypothesized that the consumption rates of leaves of Eucalyptus and their effects on the growth and survival of shredders could be predicted by leaf chemistry and toughness. The larvae preferred to feed on soft leaves (H. dusenii and M. chartacea) independently of the content of nutrients (N and P) and secondary compounds (total phenolics). When such leaves were absent, they preferred E. globulus and did not consume the tough leaves (M. lineata and S. pohlii). In monodietary experiments, leaf consumption and FPOM production differed among the studied leaves, and the values observed for the E. globulus treatments were intermediate between the soft and tough leaves. The larvae that fed on H. dusenii and M. chartacea grew constantly over five weeks, while those that fed on E. globulus lost biomass. Larval survival was higher on leaves of H. dusenii, M. chartacea and S. pohlii than on E. globulus and M. lineata leaves. Although E. globulus was preferred over tougher leaves, long-term consumption of leaves of the exotic species may affect the abundance of T. gracilis in the studied stream. Additionally, our results suggest that leaf toughness can be a determining factor for the behavior of shredders where low-quality leaves are abundant, as in several tropical streams. [ABSTRACT FROM AUTHOR]

The presence of canopy cover may influence the amount of organic detritus and stored water in bromeliad tanks and, consequently, the colonization of these ecosystems by aquatic invertebrates. The aim of this study was to determine the effects of canopy cover on the colonization of the tank-bromeliad Aechmea lingulata in the restinga, an ecosystem composed of a variety of plant communities in the sandy coastal plains of Brazil. We hypothesized that the taxonomic composition of invertebrate communities would differ between bromeliads covered and not covered by a dense canopy (shaded and unshaded bromeliads). Prior to the beginning of the experiment, bromeliads of similar size were carefully washed to remove all organisms and organic detritus, and their tanks were filled with 1.0 L of spring water. On days 7, 14, 21, 30, 45, 60 and 90, four bromeliad tanks of each shade treatment were sampled to determine invertebrate communities, stored water and organic detritus. Average daily values of water temperature and light intensity were higher in unshaded than in shaded bromeliads. The amount of fine particulate organic matter (FPOM) and stored water did not differ between treatments, but the amount of coarse particulate organic matter (CPOM) was higher in shaded bromeliads. Ostracoda, Hydracarina and Oligochaeta were the most abundant taxa in bromeliad tanks. Among insects, Culicidae, Chironomidae and Ceratopogonidae were the most representative. Invertebrate colonization occurred quickly and values of abundance were higher in unshaded bromeliads compared to shaded bromeliads. The values for biomass and richness did not differ between treatments or colonization times, and the taxonomic composition of invertebrate communities was similar throughout the experiment. Our results showed that canopy cover had a small influence on the colonization of tanks of A. lingulata in restinga, not corroborating the proposed hypothesis. These findings were likely due to the lack of variation in environmental conditions that are relevant to the colonization process, such as stored water and FPOM. However, because the amounts of CPOM were higher in shaded bromeliads, the taxonomic composition of invertebrate communities could have differed if typical shredders were present. [ABSTRACT FROM AUTHOR]

The Mikania laevigata (Asteraceae) is a Brazilian medicinal plant used to treat respiratory tract diseases. It is produced on a large scale for phytotherapic formulation. No studies on the endophytes of Mikania laevigata have been described in the literature. The endophytic fungi isolated from the leaves of M. laevigata cultivated in a floral garden located in the south region of the Bahia state, Brazil, were investigated. After surface disinfection, the performing the isolation procedure, a total of forty endophytic fungi were obtained and grouped into different morphospecies. The fungi were characterized by molecular sequencing the ITS rDNA regions, and they were identified by comparing the results published Gen Bank sequences. The phylogenetic analyses revealed four major clades of fungi from the sequenced ITS-rDNA regions: Nodulisporium sp. (3 isolates), Hypoxylon sp. (3 isolates), Daldinia sp. (1 isolate) and Xylaria luteostromata (aunique isolate).The Xylariaceae Genus was the dominant group of fungi associated with Mikania laevigata. [ABSTRACT FROM AUTHOR]

The objective of the present work was to determine the effects of colored shading on the density of glandular and tectorial trichomes, and on the yield, productivity and composition of the essential oil of Ocimum selloi Benth. Plants were cultivated for 90 days under full sunlight or under ChromatiNet 50% red or blue netting. The highest density of glandular trichomes was observed in plants that had received full sunlight. None of the light treatments altered the yield of oil, although productivity was higher in plants grown under full sunlight by virtue of the greater leaf biomass that accumulated under such conditions. The compositions of the oils varied according to the quality of light. Although the qualitative profiles of the oils of plants grown under full sunlight or red shading were similar, that obtained from plants grown under blue shading presented a larger number of constituents. The highest level of methyl chavicol (93.2%), the major component of the oil, was observed in plants grown under full sunlight. [ABSTRACT FROM AUTHOR]

Ocimum selloi is an herbal species popularly used in Brazil as antispasmodic. Herein, we report the antispasmodic effect of O. selloi essential oil (OS) in segments of guinea-pig ileum. OS did not reduce the tonus of the ileum. In contrast, OS reduced the contraction induced by carbachol (100 μM), BaCl2 (0.03 M) and low- and high-K(+) concentrations (25 and 60 mM, respectively). OS shifted the concentration-response curve for calcium to the right in a parallel manner. GC/MS analysis showed that OS consists mostly of methyl chavicol (97.57%). These results suggest that OS antispasmodic effect is mediated through calcium channel blockade. In addition, OS effect and mode of action could be accounted for methyl chavicol.

Ocimum selloi essential oil (2, 20, and 200 mg/kg; p.o.) reduced, in a dose-dependent way, the abdominal contraction induced by acetic acid (0.6%; i.p.) and the diarrhea episodes induced by castor oil in mice. At the higher dose (200 mg/kg; p.o.), the essential oil significantly reduced intestinal transit (P<0.05) in the charcoal meal test. The main component detected in O. selloi essential oil was methyl chavicol (98%; GC and GC/MS).These effects seems to support the use of O. selloi against diarrhea, intestinal spasm and visceral pain.