Suppression of Rust and Brown Eye Spot Diseases on Coffee by Phosphites and By‐products of Coffee and Citrus Industries

The rust and brown eye spot, caused by Hemileia vastatrix and Cercospora coffeicola, respectively, are the most important fungal diseases on coffee in South America. Their management is mainly by chemical treatment, and there is no genetic resistance to brown eye spot known so far. Considering the need for developing alternative products for their control, the goal of this work was to evaluate the effects of phosphites and by‐products of coffee and citrus industries on rust and brown eye spot. Formulations of coffee and citrus industry by‐products, phosphites and their combination with fungicide were evaluated in field experiments, and their effect on fungal urediniospores and conidia was evaluated in vitro. In the field, treatments were applied individually or in combination and the in vitro assays were performed with manganese phosphite (Reforce Mn), potassium phosphite and citrus industry by‐product (Fortaleza), copper phosphite and coffee industry by‐product (Fitoforce Full), and fungicide. The severity and incidence of rust and brown eye spot on coffee leaves, yield, and leaf retention were evaluated in the field. Percentage of spore germination was evaluated in vitro for both fungi, whereas mycelial growth was evaluated for C. coffeicola only. The treatments Fortaleza, Reforce Mn and Fitoforce Full suppressed both diseases with a reduction in defoliation. In the year 2012, the plants treated with Reforce Mn and Reforce Mn + Fortaleza showed a yield increase of 72 and 88%, respectively, which was similar to the results shown by the fungicide treatment. In vitro inhibition of germination of H. vastatrix urediniospores and of C. coffeicola conidia was observed and suggests that the products exert some toxic effects to both fungi. Finally, the results observed indicate that the combined use of by‐products of plant‐processing industries and phosphites is an alternative and can be added efficiently to the management of coffee diseases.     

Length–weight relationships of five fish species of headwater streams from upper Paraná River Basin,Southeastern Brazil

The length‐weight relationships (LWRs) of five fish species are reported. The fishes were sampled between September and December 2016 with seine net (4 mm mesh size) in 15 headwater streams from the upper Paraná River basin, Southeastern Brazil.     

Assessing Genetic Diversity of Brazilian Reef Fishes by Chromosomal and DNA Markers

Little is known on genetics of Brazilian coral reef fish and most of this information is limited to chromosome characterization of major representative species. The diploid chromosome number in marine fish varies from 2n= 22–26 to 2n = 240–260. Despite of this apparent diversity, most studied marine species have a diploid complement with 48 acrocentric chromosomes. This latter trend is mostly observed among Perciformes, an important major taxon of coral reef fishes. Studies in the families Pomacentridae, Pomacanthidae and Chaetodontidae, for example, have shown a common karyotype pattern entirely formed by 48 uniarmed chromosomes. However, rare numerical and structural chromosome polymorphisms and cryptic chromosome rearrangements involving heterochromatin segments and/or nucleolar organizing sites have been reported among such fishes. Although new chromosome forms can contribute to the establishment of genetically isolated populations, their role in reef fish speciation at marine realm still is an open question. More recently, genomic DNA analyses using RAPD and microsatellites, and sequencing and RFLP of mitochondrial DNA have increasingly been used in Atlantic reef fish species. Genetic homogeneity over wide geographical ranges has been reported for different fish groups, in contrast to several cases of population substructuring related to environmental constraints or evolutionary history. Amazonas outflow and upwelling on the Southeastern coast of Brazil are believed to be strong barriers to dispersal of some reef species. Moreover, it is suggested that the pattern of speciation and population structure at South Atlantic is quite distinctive from Pacific Ocean, even when comparing closely related taxa. Further genetic studies are strongly encouraged in Brazilian reef fishes in order to provide a reliable scenario of the genetic structure in this important and diverse fish group.     

Contemporary pollen flow,mating patterns and effective population size inferred from paternity analysis in a small fragmented population of the Neotropical tree <Emphasis Type="Italic">Copaifera langsdorffii</Emphasis> Desf. (Leguminosae-Caesalpinioideae)

Pollen flow and dispersal patterns were investigated in a small, isolated forest fragment of the Neotropical insect pollinated tree Copaifera langsdorffii, using paternity analysis and eight microsatellite loci. We also investigated the coancestry and effective population size of progeny arrays for conservation and environmental restoration purposes. Open-pollinated seeds were collected from 15 seed trees within the forest fragment, in which all adult trees were mapped, measured and genotyped. Twenty seeds were also collected from the nearest neighbor tree located 1.2 km from the forest fragment. Our results show that levels of genetic diversity were significantly higher in adults than offspring and significant levels of inbreeding were detected in offspring (F = 0.226). From paternity analysis, we observed low levels of selfing (s = 8%) and pollen immigration (m = 8%) in the fragment, but very high levels were detected for the isolated tree (s = 20%; m = 75%), indicating that the population and the tree are not reproductively isolated and are connected by patterns of long distance pollen dispersal (maximum detected 1,420 m). Within the forest fragment, the pattern of pollen dispersal was a near neighbor pattern with 49% of the pollen being dispersed within 50 m. The effective population size of the progeny array was low, indicating the need to collect seeds from a large number of seed trees (at least 76) for conservation purposes. The results show that the spatial isolation of the population and isolated tree due to forest fragmentation has not disrupted genetic connectivity; however, spatial isolation does seem to increase selfing and correlated mating.     

Fast-acting excitatory amino acids are involved in the enhancement of the aversiveness of the electrical stimulation of the inferior colliculus by systemic injections of muscimol

Gradual increases in the electrical stimulation of the inferior colliculus produces progressive aversive responses from vigilance, through freezing, until escape. These responses are probably mediated by excitatory amino acids (EAA) mechanisms as microinjection of glutamate into the inferior colliculus can trigger freezing responses while microinjections of NMDA cause a mixture of immobility and escape responses. Moreover, it has been shown that the neural substrates for defensive behavior in this structure are regulated by GABA-benzodiazepine mechanisms. Indeed, these responses are depressed by muscimol and midazolam locally injected into the inferior colliculus. In this work we were interested in knowing how GABAergic mechanisms interact with the EAA-mediated neural substrates of aversion generated at the inferior colliculus level. We found that while intraperitoneal injections of muscimol caused the expected antiaversive effects, unexpectedly systemic injections of muscimol enhanced the aversive reactions induced by electrical stimulation of the inferior colliculus of rats. Local injections into the central nucleus of the inferior colliculus of GDEE-an AMPA/kainate receptor antagonist-inhibited whereas AP7-a NMDA receptor antagonist-did not influence these responses. It is suggested that systemic injections of muscimol inhibit GABAergic inputs to the inferior colliculus. The removal of these inhibitory influences reduce the well-known tonic inhibitory control exerted by GABAergic mechanisms on the neural substrates of aversion of the inferior colliculus. Activation of these neural substrates by fast-acting AMPA/kainate receptors trigger the initial steps of the defense reaction in the central nucleus of the inferior colliculus.     

Impact of biostimulant and saline water on cape gooseberry (Physalis peruviana L.) in Brazil

Production of Physalis peruviana L. has gained prominence in Northeastern Brazil. However, salinity limits the crop development in the Brazilian semiarid. Thus, this research aimed to evaluate the application of Acadian® biostimulant as mitigant of the deleterious effects of salinity on growth and gas exchange of P. peruviana plants. The experiment was combining different electrical conductivity of irrigation water (0.50, 1.23, 3.00, 4.44, and 5.50 dS m⁻¹) and biostimulant doses (0.00, 1.45, 5.00, 8.55, and 10.00 mL L⁻¹). The main variables evaluated were plant height, stem diameter, number of leaves, root length, leaf area, specific leaf area, leaf area ratio, absolute and relative growth rate for plant height, and gas exchange. Experimental results showed that an increase in electrical conductivity of irrigation water had negatively affected the growth components and gas exchange in P. peruviana. Also, the application of seaweed-based biostimulant improves the photosynthetic capacity (43.3%), reduces transpiration rate (26.5%) and water loss by this process, further it attenuated the deleterious effects of salinity on specific leaf area, leaf area ratio, and stomatal conductance. To further elucidate the effectiveness of biostimulant application as a mitigant of salt stress, research aimed at the biochemical and enzyme activities of the plant''s antioxidant system should be conducted to better understand this process.     

Synthetic Chalcone Derivatives as Inhibitors of Cathepsins K and B,and Their Cytotoxic Evaluation

A series of chalcone derivatives, 1 – 15 , were prepared by Claisen? Schmidt condensation and evaluated for their cytotoxicities on tumor cell lines and also against proteolytic enzymes such as cathepsins B and K. Of the compounds synthesized, (E)‐3‐(3,4‐dimethoxyphenyl)‐1‐phenylprop‐2‐en‐1‐one ( 12 ), (E)‐3‐(4‐chlorophenyl)‐1‐phenylprop‐2‐en‐1‐one ( 13 ), (E)‐3‐(4‐methoxyphenyl)‐1‐phenylprop‐2‐en‐1‐one ( 14 ), and (E)‐3‐(4‐nitrophenyl)‐1‐phenylprop‐2‐en‐1‐one ( 15 ) showed significant cytotoxicities. The most effective compound was 15 , which showed high cytotoxic activity with an IC₅₀ value lower than 1 μg/ml, and no selectivity on the tumor cells evaluated. Substituents at C(4) of ring B were found to be essential for cytotoxicity. In addition, it was also demonstrated that some of these chalcones are moderate inhibitors of cathepsin K and have no activity against cathepsin B.     

Biomarkers for susceptibility to infection and disease severity in human malaria

Malaria remains a major infectious disease that affects millions of people. Once infected with Plasmodium parasites, a host can develop a broad range of clinical presentations, which result from complex interactions between factors derived from the host, the parasite and the environment. Intense research has focused on the identification of reliable predictors for exposure, susceptibility to infection and the development of severe complications during malaria. Although most promising markers are based on the current understanding of malaria immunopathogenesis, some are also focused more broadly on mechanisms of tissue damage and inflammation. Taken together, these markers can help optimise therapeutic strategies and reduce disease burden. Here, we review the recent advances in the identification of malarial biomarkers, focusing on those related to parasite exposure and disease susceptibility. We also discuss priorities for research in biomarkers for severe malaria.     

Olfactory response of predatory mites to vegetative and reproductive parts of coconut palm infested by <Emphasis Type="Italic">Aceria guerreronis</Emphasis>

The phytophagous mite Aceria guerreronis Keifer is an important pest of coconut worldwide. A promising method of control for this pest is the use of predatory mites. Neoseiulus baraki (Athias-Henriot) and Proctolaelaps bickleyi Bram are predatory mites found in association with A. guerreronis in the field. To understand how these predators respond to olfactory cues from A. guerreronis and its host plant, the foraging behavior of the predatory mites was investigated in a Y-tube olfactometer and on T-shaped arenas. The predators were subjected to choose in an olfactometer: (1) isolated parts (leaflet, spikelet or fruit) of infested coconut plant or clean air stream; (2) isolated parts of non-infested or infested coconut plant; and (3) two different plant parts previously shown to be attractive. Using T-shaped arenas the predators were offered all possible binary combinations of discs of coconut fruit epidermis infested with A. guerreronis, non-infested discs or coconut pollen. The results showed that both predators were preferred (the volatile cues from) the infested plant parts over clean air. When subjected to odours from different infested or non-infested plant parts, predators preferred the infested parts. Among the infested plant parts, the spikelets induced the greatest attraction to predators. On the arenas, both predators preferred discs of coconut fruits infested with A. guerreronis over every other alternative. The results show that both predators are able to locate A. guerreronis by olfactory stimuli. Foraging strategies and implications for biological control are discussed.     

Leishmania?braziliensis-Reactive T Cells Are Down-Regulated in Long-Term Cured Cutaneous Leishmaniasis,but the Renewal Capacity of T Effector Memory Compartments Is Preserved

Leishmania (Viannia) braziliensis control and tissue damage relate to the effector immune response, which in turn affects clinical outcome. Leishmania reactive CD4⁺ and CD8⁺ T cells are expanded in long-term healed cutaneous leishmaniasis (hCL) patients but their functional characteristics remain to be determined. This study investigates antigen-specific recall in long-term healed CL caused by L. braziliensis infection. Healed CL subjects were grouped according to the time elapsed since the end of therapy: less than two years and two to five years. Activation phenotype (CD69⁺ or CD25⁺) and subpopulations of memory T cell phenotypes [central memory (Tcm): CD45RO⁺ CCR7⁺ or effector memory (Tem): CD45RO⁺ CCR7^-] were quantified in ex vivo blood mononuclear cells and after Leishmania antigens stimuli. A reduction in the percentage of activated Leishmania-responder CD4⁺ and CD8⁺ T cells in hCL was associated with the time elapsed since clinical cure. Percentage of CD69⁺ in TCD4⁺ and TCD8⁺ cells were negatively correlated with IL-10 levels. Ex vivo analyses showed contracted Tem CD4⁺ and Tem CD8⁺ compartments from hCL with long time elapsed since clinical cure, although renewal of these compartments was observed following in vitro exposure to leishmanial stimuli. Our results show that healed L. braziliensis infected patients exhibit a recall response to Leishmania antigens with evident expansion of effector memory T cells. Regulated leishmanial-specific response seems to emerge only about two years after initial contact with the parasite antigens.