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Made available in DSpace on 2018-11-26T17:48:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Assessment of host infection and distribution patterns are crucial to understand the underling mechanisms that shape parasitic plant spread in natural ecosystems. However, such data remain scarce for mistletoes inhabiting Brazilian campo rupestre vegetation, old-growth montane fire-prone grasslands. We evaluated the host range and distribution patterns of the mistletoe Psittacanthus robustus (Loranthaceae) at seven 1-ha plots located at in Serra do Cipo, southeastern Brazil. We investigate if the frequency of parasitism by P. robustus is directly related to the relative abundance of host tree species in the community, and how prevalence and intensity of infection vary among different host tree species. Average mistletoe density was 120 individuals ha(-1), which parasitized eight host species, including trees and shrubs in five families. Four tree species, Vochysia thyrsoidea, Qualea cordata (Vochysiaceae), Trembleya laniflora and Miconia ferruginata (Melastomataceae), comprised 95% of infected individuals. Twenty two percent of 1,108 trees sampled were parasitized by P. robustus, with host specificity within species in Myrtales Clade. Prevalence increased with host height for all tree species, with a highly aggregated distribution in few taller host trees within rocky outcrop patches in campo rupestre. The unveiling patterns of host infection and mistletoe distribution, support future studies addressing plant-plant, bird-plant and fire-plant interactions that might shape infection dynamics of this widespread mistletoe species in campo rupestre. (c) 2017 Elsevier GmbH. All rights reserved. Univ Estadual Campinas, Inst Biol, Programa Posgrad Ecol, BR-13083970 Campinas, SP, Brazil Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Bot, BR-31270901 Belo Horizonte, MG, Brazil Univ Estadual Paulista, Dept Zool, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Campinas, Inst Biol, Dept Biol Anim, CP 6109, BR-13083970 Campinas, SP, Brazil Univ Estadual Paulista, Dept Zool, BR-13506900 Rio Claro, SP, Brazil FAPESP: 2007/59444-4

In T. cruzi, a causative agent of Chagas disease, phosphoenolpyruvate carboxykinase (TcPEPCK) is associated with carbohydrate catabolism. Due to its importance in the metabolism of the parasite, it has become a promising target for the development of new drugs against Chagas disease. Aiming to investigate different approaches for ligands screening, TcPEPCK was immobilized on amine-terminated magnetic beads (TcPEPCK-MB) and kinetically characterized by liquid chromatography tandem mass spectrometry activity assay with a KMapp value of 10 ± 1 μM to oxaloacetate as substrate. Natural products library affords highly diverse molecular frameworks through their secondary metabolites, herein a ligand fishing TcPEPCK-MB assay is described for prospecting ligands in four ethanolic extracts of Brazilian Cerrado plants: Qualea grandiflora (Vochysiaceae), Diospyros burchellii (Ebenaceae), Anadenanthera falcata (Fabaceae) and Byrsonima coccolobifolia (Malpighiaceae). The chemical characterization of eleven identified ligands was carried out by liquid chromatography tandem high-resolution mass spectrometry experiments. Senecic acid, syneilesinolide A, phytosphingosine and vanillic acid 4-glucopyranoside are herein reported for the first time for Q. grandiflora, D. burchellii, A. falcata, respectively. In addition, the specificity of the assay was observed since only catechin was fished out from the ethanolic extract of B. coccolobifolia leaves, despite the presence of epicatechin epimer.

We examine the eudicot order Myrtales, a clade with strong Gondwanan representation for most of its families. Although previous phylogenetic studies greatly improved our understanding of intergeneric and interspecific relationships within the order, our understanding of inter-familial relationships still remains unresolved; hence, we also lack a robust time-calibrated chronogram to address hypotheses (e.g., biogeography and diversification rates) that have implicit time assumptions. Six loci (rbcL, ndhF, matK, matR, 18S, and 26S) were amplified and sequenced for 102 taxa across Myrtales for phylogenetic reconstruction and ten fossil priors were utilized to produce a chronogram in BEAST. Combretaceae is identified as the sister clade to all remaining families with moderate support, and within the latter clade, two strongly supported groups are seen: (1) Onagraceae+Lythraceae, and (2) Melastomataceae+the Crypteroniaceae, Alzateaceae, Penaeaceae clade along with Myrtaceae+Vochysiaceae. Divergence time estimates suggest Myrtales diverged from Geraniales ∼124Mya during the Aptian of the Early Cretaceous. The crown date for Myrtales is estimated at ∼116Mya (Albian-Aptian). BioGeoBEARS showed significant improvement in the likelihood score when the "jump dispersal" parameter was added. South America and/or Africa are implicated as important ancestral areas in all deeper nodes. BAMM analyses indicate that the best configuration included three significant shifts in diversification rates within Myrtales: near the crown of Melastomataceae (∼67-64Mya), along the stem of subfamily Myrtoideae (Myrtaceae; ∼75Mya), and along the stem of tribe Combreteae (Combretaceae; ∼50-45Mya). Issues with conducting diversification analyses more generally are examined in the context of scale, taxon sampling, and larger sets of phylogenetic trees.

The ant-plant mutualism mediated by extrafloral nectaries (EFNs) is based on the provision of extrafloral nectar (a sugar-rich liquid) in exchange for ant defense against herbivores. The extrafloral nectar production can vary depending on the intensity or types of leaf damage caused by different mouthparts of insect herbivores (i.e., sucking or chewing insects). However, it is poorly known how the type of herbivore damage changes the outcomes of tri-trophic interactions. Here, we address how the damage inflicted by different herbivore groups affects extrafloral nectar production and ants’ attendance and aggressiveness. Through an experimental field study, we tested whether the type of leaf damage, sucking or chewing, changes extrafloral nectar volume and sugar concentration, and subsequently ant composition and behavior. We evaluated the extrafloral nectar production and ant attendance and aggressiveness before and after simulated herbivory in Qualea parviflora (Vochysiaceae), a Brazilian savanna EFN-bearing plant. We found that only plants with sucking damage increased the sugar concentration of their extrafloral nectar, only plants with chewing damage increased ant abundance, and surrogate herbivore predation differed before and after simulated herbivory only for sucking damage. We provided the first evidence that the type of damage can influence ant aggressiveness via changes in extrafloral nectar production, translating to changes in the outcomes of this ant-plant mutualism. Ultimately, studies should consider the effects of herbivore damage type when studying insect-plant interactions.

a b s t r a c t Knowledge about plant defense systems against herbivory is crucial to understanding trophic relation- ships in terrestrial ecosystems. Distinct defenses may act either alone or in combination during foliar sprouting. In our study, we explored the effect of the three most conspicuous defenses found in the leaves of Qualea multiflora (Vochysiaceae) during foliar sprouting, which are: (1) the presence of tri- chomes, (2) foliar toughness and (3) activity of extrafloral nectaries (EFNs). In addition, we quantified foliar herbivory at different leaf stages. We determined that the three defenses evaluated vary in effec- tiveness during leaf development. The number of trichomes was higher during early leaf development, toughness at the end, and the activity of EFNs (biotic defense) during the middle period. Foliar herbivory was similar at different leaf ages. The results indicate that Q. multiflora synchronizes its foliar defenses in order to optimize performance in anti-herbivory protection over time.

This study aimed to isolate and characterize microsatellite markers for Qualea grandiflora and to test their transferability to congeneric species Qualea multiflora and Qualea parviflora. These three species are widespread in the Cerrado, the largest, richest and probably the most threatened tropical savanna in the world. We characterized ten markers in 40 individuals belonging to two populations of Q. grandiflora and eight markers in 20 individuals belonging to one population of Q. multiflora and Q. parviflora. In Q. grandiflora, considering all 40 analyzed individuals, the number of alleles per locus ranged from eight to 21, and the average was 11.60. The mean number of alleles per locus was 8.8 and 7.3 in each population. The observed and expected heterozygosities (Ho and He) within populations varied from 0.235 to 0.944 and from 0.225 to 0.932, respectively. In Q. multiflora the number of alleles varied from two to 11 with an average of 5.75; the Ho ranged from 0.150 to 0.950, while He ranged from 0.191 to 0.817. In Q. parviflora, considering the seven polymorphic loci, the number of alleles ranged from two to 13, with an average of 7.5, while Ho ranged from 0.211 to 0.944, and He ranged from 0.193 to 0.906. The polymorphism level of the microsatellite markers here described enable them as powerful tools for future population genetic studies in these species, helping to answer ecological and evolutionary questions.

Ethnopharmacological relevance The species Qualea grandiflora and Qualea multiflora , which belong to the Vochysiaceae family, are common in the Brazilian savannah (Cerrado biome), and the local inhabitants use these species to treat external ulcers and gastric diseases and as an anti-inflammatory agent. Studies have demonstrated that these plants contain compounds that exhibit pharmacological activities; however, the risks associated with their consumption are not known. Material and methods In the present study, the mutagenicity of polar and apolar extracts from Qualea grandiflora and Qualea multiflora were assessed by employing the Ames assay with and without metabolic activation. Additionally, phytochemical analyses (HPLC–ESI-IT-MS, HPLC–UV-PDA and GC–IT-MS) were performed to identify the chemical constituents present in these species, including the evaluation of physico-chemical properties, such as polarity or apolarity of the organic compounds, which are related to each fraction obtained. These studies provide important information regarding the biochemical behaviour of these compounds. Results All extracts exhibited mutagenicity, inducing frameshift mutations and base substitutions in DNA. Phytochemical analysis identified terpenes, ellagic acid derivatives and phytosteroids. Conclusions The mutagenicity observed might be due to the presence of pentacyclic triterpenes and polyphenols, which are able to generate reactive oxygen species (ROS) and result in the potential to cause DNA damage. The genetic risk identified in this present work shows that special attention should be considered for the use of compounds obtained from these plant species in medicinal treatments. Further studies must be conducted to identify safe therapeutic doses.

We investigated the pattern of aluminum (Al) accumulation in leaf tissues of native hyperaccumulator Vochysiaceae species Qualea grandiflora, Callisthene major, and Vochysia pyramidalis, from the Brazilian Cerrado. Non-accumulator Sclerolobium paniculatum was used as a control species. We expected a strong compartmentalization of Al in non-active leaf cell compartments such as cell walls and vacuoles in Al-accumulating species and the absence of Al in critical metabolic sites such as the chloroplasts. Plant leaves were harvested in the field and cut in small segments for histological analysis; hematoxylin dye was used for Al localization in tissues. Results of soil analysis of the three sites and the concentration of Al in leaves indicated that there is no direct relationship between Al availability in soils and Al hyperaccumulation among the Vochysiaceae species evaluated. The cross-sections of leaf tissues showed hematoxylin color in the palisade and spongy parenchyma cells (chloroplast) of Q. grandiflora and C. major. The vascular system of Q grandiflora was not colored, but some cells from the xylem region of C. major were stained. In contrast, the adaxial and abaxial epidermal cells of V. pyramidalis were colored by hematoxylin, as were some cells from the vascular bundle, but color formation was not observed in the cells of palisade parenchyma. Al was not detected in leaves of S. paniculatum. We concluded that, although hyperaccumulation of Al is a common trait in the Vochysiaceae family, the processes of storage and detoxification in leaf tissues differ among the species. Two of the three hyperaccumulator species use chloroplasts as a sink for Al, with no apparent signs of toxicity. Therefore, the physiological role of Al in plant tissues remains to be elucidated. (C) 2010 Elsevier B.V. All rights reserved.

Distribution of parasitic plants is directly linked with the distribution of host species and behavioral patterns of seed dispersers. Psittacanthus robustus (Loranthaceae) is a neotropical hemiparasite that mainly colonizes species of the family Vochysiaceae. Vochysia thyrsoidea is the main host of P. robustus and is commonly found in areas of cerrado rupestre (rocky savanna), an abundant vegetation in our study site. We conducted the study in the ecological park Parque Ecologico Quedas do Rio Bonito (PEQRB), over an area of 2.82 ha of cerrado rupestre . The objective of this work was to investigate population structure, parasitic behavior (mistletoe grip height and circumference of host branch), and spatial distribution of Psittacanthus robustus on a population of Vochysia thyrsoidea . We sampled 267 V. thyrsoidea individuals and found that the population had a random distribution pattern. Seventy-nine individuals (29.6% of the sample population) hosted the hemiparasite, to a total of 193 P. robustus individuals. The number of mistletoe individuals per host plant ranged between 1 and 12. The V. thyrsoidea individuals most infested with mistletoes were those reaching greater heights. The correlation between height of host plant and preferred grip height was highly significant, with the preferred grip height being the uppermost portions of host plants. The crown size of P. robustus individuals ranged between 10 and 230 cm. The main disperser of P. robustus fruit was found to be swallow-tanager Tersina viridis viridis . Its activities led to a clumped pattern of spatial distribution of the hemiparasite along with higher infestation in larger trees.

The polysaccharide (VTh) extracted with water from the gum exudate of the trunk Vochysia thyrsoidea gave a solution of high viscosity and was homogeneous, with M w 92.5 × 10 3 and d n /d c = 0.212. Partial hydrolysis gave a main chain of →4)-β- d -Glc p A-(1 → 2)-α- d -Man p -(1→ repeating groups. Since VTh contained 24% GlcA, neither its monosaccharide ratio (GC–MS of alditol acetates) nor methylation results were accurate. It was therefore carbodiimide-reduced to CR 3 VTh, which contained Ara, Xyl, Man, Gal, and Glc in a molar ratio of 28:4:29:19:25: methylation analysis showed mainly nonreducing end-units of Ara f (25%), Ara p (8%), and Gal p (8%) and side-chain units of 3- O - (6%) and 3,4-di- O -subst. Gal p (12%). Main-chain units of Man p were 2,3-di- O -substituted (17%), showing that they were substituted at O-3 by side chains, but there was less side-chain substitution of Glc p units, which were mainly 4- O -substituted (12%). Most Ara f units in VTh and CR 3 VTh were single nonreducing end-units, and were present in groups of α- l -Ara f -(1 → 3)- d -Man p and α- l -Ara f -(1 → 3)-[α- l -Ara f -(1 → 4)]-β- d -Gal p -(1 → 3)-α- d -Man p . Other degradation products derived from VTh agreed with this structure. The degree of side-chain substitution of the same main chain was greatest with the gum exudate polysaccharide of V. tucanorum , and progressively less with those of V. thyrsoidea , and V. lehmannii . High-viscosity aqueous solutions were formed by the gum of V. thyrsoidea , in contrast with those of V. lehmannii and V. tucanorum .

The distribution of seed fatty acids of 16 species of Vochysiaceae native to Brazil, corresponding to the genera Callisthene , Qualea , Salvertia and Vochysia , and amounting to 57 samples, were studied. The methyl esters of the fatty acids were analyzed by GC–EIMS. For most species, fatty acid patterns are seemingly useful for species characterization. Intraspecific variability of samples of Salvertia grandiflora seems to have geographic significance. With one exception, palmitic and oleic acids predominate in the fatty acids distribution of Qualea and Callisthene . Q. grandiflora possesses exceptional amounts of lauric acid. Relatively high amounts of either C 20– C 22 (saturated or monounsaturated) or stearic acids characterize Salvertia and Vochysia . UPGMA analysis of fatty acids distribution based on Euclidean distances resulted in a cluster combining Callisthene and all samples of Qualea , except Q. grandiflora . Samples of Vochysia are combined into several clusters. The dendrogram is suggestive of taxonomic relationships, allowing the distinction of taxa down to the sub-sectional level. V. pyramidalis , from section Ciliantha , subsection Ferrugineae , has closer chemical affinities with species of section Vochysiella , subsection Decorticantes . Comparing with monomers of polysaccharide seed cell walls of Vochysiaceae, fatty acid patterns revealed lower intraspecific variability and higher taxonomic resolution.

A total of 3029 cuttings were harvested from coppiced stumps of 96 trees representing six provenances of Vochysia guatemalensis. There was significant variation in diameter between provenances with tree stumps from La Ceiba in Honduras being the largest with a mean of 13.4 cm compared with 10.5 cm for Siquirres in Costa Rica. Regression analysis was utilised to determine the influence of provenance and diameter on the numbers of coppice shoots produced by each tree and the subsequent rooting ability of cuttings taken from them. Significantly more shoots and cuttings were produced on trees with larger diameters. There was also a significant provenance influence on shoot and cutting production. The fitted regression model predicted a difference of 20 cuttings from stumps of the same diameter between provenances Florencia, Costa Rica and La Ceiba, Honduras. In contrast to the positive effect of large stump diameter on the number of cuttings produced, the rooting ability of cuttings was negatively influenced by the diameter of the stump. The average rooting percentage of cuttings from individual provenances varied between 30% and 70% with an overall rooting percentage of 64%. The implications of these results for commercial vegetative propagation programmes are discussed.

The powdery mildew Uncinula heringeriana from leaves of Qualea grandiflora is described and validated. Uncinula viegasii sp. nov. from leaves of Q. parviflora , and U. alvimii sp. nov. from leaves of Bowdichia virgilioides are described from the cerrado of central Brazil. A key for identification of South American species of Uncinula is provided.

Vochysia divergens Pohl (Vochysiaceae) is a tree commonly found in wet soils of ‘Pantanal’ of Mato Grosso, Brazil, and used in folk medicine against infections and asthma. We have studied different extracts and some isolated compounds from this plant for antibacterial activity. From the extracts of the stem bark β-sitosterol, betulinic acid and sericic acid were isolated. The minimal inhibitory concentration (MIC) for Staphylococcus aureus were: ethanolic extract (MIC = 1.5 mg/ml); ethyl acetate extract (MIC = 2.0 mg/ml); and sericic acid (MIC = 1.0 mg/ml). Escherichia coli was resistant until 5 mg/ml.

Two trees of the family Vochysiaceae, Vochysiaferruginea and Qualea paraensis, were abundant in a Nicaraguan rainforest which was heavily damaged by Hurricane Joan in 1988, and both had recovered their previous densities by 1993. However, their regeneration followed quite different paths. Vochysia suffered complete mortality of adult trees in the hurricane, but rapid growth and high survivorship of its abundant seedlings and sprouts of saplings, restored its population density (though not yet its mean diameter at breast height) and indeed led to spatial ex- pansion. Qualea, however, showed 100% survival of trees during the hurricane but substantial mortality in the following years. Although seedlings and sprouts of Qualea are quite rare, ingrowth is sufficient to maintain the population so far. However, vine growth on Qualea (unlike Vochysia) is substantial. These two species are thus contrasting elements of the 'direct regeneration' which has been observed in this rainforest. The Vochysia pattern of death and recovery can be described as 'resilience', while the Qualea pattern of survival can be called 'resistance'. The regenerating Vochysia population is mostly seedlings and saplings, while that of Qualea is mostly adult trees. Depending on the pattern of regeneration, different management strategies will be appropriate for maintaining tree species subject to natural disturbances such as hurricanes and/or artificial ones such as logging.

A new rust fungus, Aplopsora hennenii sp. nov., is described on Qualea multiflora from the Brazilian cerrado. This is the first record of a member of the Uredinales on the Vochysiaceae.

The trunk wood of Qualea labouriauana contains, besides (2 R )-5,7,4′-trihydroxy-3′-methoxy-6,8-dimethylflavanone, (2 R )-5,7,4′-trihydroxy-8-methylflavanone, the biosynthetically interesting 2,2′-dihydroxy-4,6,4′,6′-tetramethoxy-3,3′-dimethylbenzophenone. From the trunk wood extract of Q. paraensis the first named flavanone crystallized out directly.

3,3′-Di-O-methyl and 3′-O-methyl-3,4-O,O-methylidene ellagic acids have been isolated from Callisthene major.