Screening of plants found in Amazonas State for lethality towards brine shrimp

226 methanol and water extracts representing 74 mainly native plant species found in Amazonas State, Brazil, were tested at a standard concentration of 500 μg/mL for lethality towards larvae of the brine shrimp species Artemia franciscana. Several cytotoxic plant species were identified in this work: Aspidosperma marcgravianum, A. nitidum, Croton cajucara, Citrus limetta, Geissospermum argenteum, Minquartia guianensis, Piper aduncum, P. amapense, P. capitarianum, P. tuberculatum and Protium aracouchini. The results were analyzed within the context of the available traditional knowledge and uses for these plants.

Screening of plants found in the State of Amazonas, Brazil for activity against Aedes aegypti larvae

Ethanol, methanol and water extracts representing mostly native plant species found in the Amazon region were prepared, respectively, by maceration, continuous liquid-solid extraction and infusion, followed by evaporation and freeze-drying. The freeze-dried extracts were tested for lethality toward Aedes aegypti larvae at test concentrations of 500 mg / mL. In general, methanol extracts exhibited the greatest larvicidal activity. The following 7 methanol extracts of (the parts of) the indicated plant species were the most active, resulting in 100% mortality in A. aegypti larvae: Tapura amazonica Poepp. (root), Piper aduncum L. (leaf and root), P. tuberculatum Jacq. (leaf, fruit and branch). and Simaba polyphylla (Cavalcante) W.W. Thomas (branch).

Biomass accumulation, photochemical efficiency of photosystem II, nutrient contents and nitrate reductase activity in young rosewood plants (Aniba rosaeodora Ducke) submitted to different NO3-:NH4+ ratios

The rosewood (Aniba rosaeodora Ducke) is a native tree species of Amazon rainforest growing naturally in acidic forest soils with reduced redox potential. However, this species can also been found growing in forest gaps containing oxide soils. Variations in the forms of mineral nitrogen (NO3- or NH4+) may be predicted in these different edaphic conditions. Considering that possibility, an experiment was carried out to analyze the effects of different NO3-:NH4+ ratios on the growth performance, mineral composition, chloroplastid pigment contents, photochemical efficiency photosystem II (PSII), and nitrate redutase activity (RN, E.C.1.6.6.1) on A. rosaeodora seedlings. Nine-month-old seedlings were grown in pots with a washed sand capacity of 7.5 kg and submitted to different NO3-:NH4+ ratios (T1 = 0:100%, T2 = 25:75%, T3 = 50:50%, T4 = 75:25%, and T5 = 100:0%). The lowest relative growth rate was observed when the NO3-:NH4+ ratio was equal to 0:100%. In general, high concentrations of NO3- rather than NH4+ favored a greater nutrient accumulation in different parts of the plant. For the chloroplastid pigment, the highest Chl a, Chl b, Chl tot, Chl a/b and Chl tot/Cx+c contents were found in the treatment with 75:25% of NO3-:NH4+, and for Chl b and Cx+c it was observed no difference. In addition, there was a higher photochemical efficiency of PSII (Fv/Fm) when high NO3- concentrations were used. A linear and positive response for the nitrate reductase activity was recorded when the nitrate content increased on the culture substrate. Our results suggest that A. rosaeodora seedlings have a better growth performance when the NO3- concentrations in the culture substrate were higher than the NH4+ concentrations.

In vitro screening of Amazonian plants for hemolytic activity and inhibition of platelet aggregation in human blood

In the present study, different aerial parts from twelve Amazonian plant species found in the National Institute for Amazon Research's (INPA's) Adolpho Ducke Forest Reserve (in Manaus, Amazonas, Brazil) were collected. Separate portions of dried, ground plant materials were extracted with water (by infusion), methanol and chloroform (by continuous liquid-solid extraction) and solvents were removed first by rotary evaporation, and finally by freeze-drying which yielded a total of seventy-one freeze-dried extracts for evaluation. These extracts were evaluated initially at concentrations of 500 and 100 µg/mL for in vitro hemolytic activity and in vitro inhibition of platelet aggregation in human blood, respectively. Sixteen extracts (23 % of all extracts tested, 42 % of all plant species), representing the following plants: Chaunochiton kappleri (Olacaceae), Diclinanona calycina (Annonaceae), Paypayrola grandiflora (Violaceae), Pleurisanthes parviflora (Icacinaceae), Sarcaulus brasiliensis (Sapotaceae), exhibited significant inhibitory activity towards human platelet aggregation. A group of extracts with antiplatelet aggregation activity having no in vitro hemolytic activity has therefore been identified. Three extracts (4 %), all derived from Elaeoluma nuda (Sapotaceae), exhibited hemolytic activity. None of the plant species in this study has known use in traditional medicine. So, these data serve as a baseline or minimum of antiplatelet and hemolytic activities (and potential usefulness) of non-medicinal plants from the Amazon forest. Finally, in general, these are the first data on hemolytic and inhibitory activity on platelet aggregation for the genera which these plant species represent.

Cryptic species in Pagamea coriacea sensu lato (Rubiaceae): evidence from morphology, ecology and reproductive behavior in a sympatric context

In this study we explore morphological and ecological variation in sympatric populations of Pagamea coriacea s.l. - a species complex from white-sand vegetation in the Amazon. A total of 147 trees were sampled and monitored at three nearby sites in Central Amazon, Brazil. Multivariate analyses of morphology indicated two distinct groups (A and B), which also differed in bark type, each containing subgroups associated with sexual dimorphism. However, a single hermaphroditic individual was observed within group B. As expected, all pistillate plants produced fruits, but 23% of the staminate plants of group B, and 5% of group A also produced fruits. This variation suggests that the sexual systems of both groups are between dioecy and gynodioecy. There was an overlap in flowering phases between the two groups, but the pattern of floral maturation differed. Ecologically, plants of group B were found in more shaded habitats and over sandstone bedrocks, while group A was prevalent in deeper sandy soils as canopy plants. The significances of morphological and environmental differences were tested by a multivariate analysis of variance, and a canonical discriminant analysis assessed the importance of variables. The coexistence in sympatry of two discrete morphological groups in the P. coriacea s.l., with different habitat preferences and reproductive behaviors, indicates they represent distinct species.

Evaluation of Sexual Dimorphism in the Efficacy and Safety of Simvastatin/Atorvastatin Therapy in a Southern Brazilian Cohort

Background: Dyslipidemia is the primary risk factor for cardiovascular disease, and statins have been effective in controlling lipid levels. Sex differences in the pharmacokinetics and pharmacodynamics of statins contribute to interindividual variations in drug efficacy and toxicity. Objective: To evaluate the presence of sexual dimorphism in the efficacy and safety of simvastatin/atorvastatin treatment. Methods: Lipid levels of 495 patients (331 women and 164 men) were measured at baseline and after 6 ± 3 months of simvastatin/atorvastatin treatment to assess the efficacy and safety profiles of both drugs. Results: Women had higher baseline levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) compared with men (p < 0.0001). After treatment, women exhibited a greater decrease in plasma TC and LDL-C levels compared with men. After adjustment for covariates, baseline levels of TC and LDL-C influenced more than 30% of the efficacy of lipid-lowering therapy (p < 0.001), regardless of sex. Myalgia [with or without changes in creatine phosphokinase (CPK) levels] occurred more frequently in women (25.9%; p = 0.002), whereas an increase in CPK and/or abnormal liver function was more frequent in in men (17.9%; p = 0.017). Conclusions: Our results show that baseline TC and LDL-C levels are the main predictors of simvastatin/atorvastatin therapy efficacy, regardless of sex. In addition, they suggest the presence of sexual dimorphism in the safety of simvastatin/atorvastatin. The effect of sex differences on receptors, transporter proteins, and gene expression pathways needs to be better evaluated and characterized to confirm these observations.

Host plants of root-knot nematodes

Root-knot nematodes were found attacking Coffea spp. and also roots of a few weed species usually found in the coffee orchards in São Paulo. C. arabica cv. Catuaí, C. arabica cv. Mundo Novo, Timor Hybrid and a few plants of C. racemosa showed to be susceptible to Meloidogyne exigua. Roots of Ageratum conyzoides, Amaranthus viridis, Bidens pilosa, Coffea arabica cv. Mundo Novo, Coffea racemosa, Commelina virginica, Digitaria sanguinalis, Galinsoga parviflora, Gnaphalium spathulatum, Porophyllum ruderale, Portulaca oleracea, Pterocaulon virgatum and Solanum americanum were disfigured by M. incognita M. arenaria was found attacking roots of Eleusine indica and Gnaphalium spathulatum, and the presence of an unidentified Meloidogyne species was verified in roots of the following species: Vernonia ferruginea, C. arabica x C. canephora, Eupatorium pauciflorum, Coffea canephora cv. Kouillou, Coffea eugenioides, Coffea racemosa, Coffea stenophylla, Euphorbia pilullifera, Solanum americanum, Ageratum conyzoides, Phyllanthus corcovadensis, and Emilia sagittata.

Infection by microorganisms on soybean seeds obtained from plants treated with growth regulators

This research, deals with the effects of exogenous growth regulators on infection by microorganisms on soybean (Glycine max cv. Davis) seeds. To study the influence of the chemicals, soybean plants were sprayed with gibberellic acid (GA) 100 ppm, (2-chloroethyl) trimethylammonium chloride (CCC) 2,000 ppm, succinic acid-2,2-dimethy1hydrazide (SADH) 4,000 ppm, indolylacetic acid (IAA) 100 ppm, 2,3,5-triiodobenzoic acid (TIBA) 20 ppm (three applications), and Agrostemin (1g/10 ml/ 3 1). Application of growth regulators did not affect infect ion by microorganisms on soybean seeds. The prominent fungus isolated was Phomopsis sojae. Alternaria and Fusarium spp. were isolated from seeds. The presence of a bacterium on the seeds was observed. The delay in harvest and high humidity increased the number of seeds from which Phomopsis was recovered.

Effects of environment on quality of tomato transplanting plants

In order to study the effects of shading and unshading combined with N fertilizing on tomato transplanting plants, an experiment in greenhouse conditions was carried on. It was concluded that N is important to produce healthy and strong plants. Under shading plus N fertilization, plants are taller and have high nitrate contents, while under unshading plus N fertilization, plants have higher diameter and more developed root system.

Nutrient deficiencies in apple plants (Pyrus malus L.)

A trial was carried out with one year old 'Ohio Beauty apples (grafted on 'Doucin'), grown on sand cu1ture, receining nutrient solutions lacking the following nutrients at the time: N, P, K, Ca, Mg, S, and B. The main conclusions are as follows: as the adequate and inadequate levels from leaf analysis were, respectively: N -2.22 and 1.53%, P - 0,17 and 0.05%, K - 1.32 and 0.33%; Ca -0.9.4 and 0.52%, Mg - 0.37 and 0.06%; S -0.18 and 0.08%; B -62 and 2k ppm.

The cassava mite complex: III - new distribution records, mainly from Colombia and Africa. References to other plants

Uma lista de novas referências e ocorrências para ácaros tetraniquídeos da mandioca é apresentada.

Sexual dimorphism in Liolaemus occipitalis (Iguania, Tropiduridae)

The sexual dimorphism in size, morphology and color of the lizard Liolaemus occipitalis Boulenger, 1885 was studied. Thirty-two adult males and twenty-eight adult females were sampled from a population in the Jardim do Éden beach, near Tramandaí, Rio Grande do Sul, Brazil. Size related sexual dimorphism occurred in all compared body dimensions. The largest female was 59.6 mm in snout-vent length, and the largest male was 69.3 mm. Males and females also presented differences in ventral and dorsal color pattern, and in the presence of pre-cloacal pores. The results suggest that, in Liolaemus occipitalis, sexual dimorphism in size is determined by sexual selection, competition between males and by the high energetic cost for females a few months after hatching.

Reproductive biology and sexual dimorphism in Cnemidophorus vacariensis (Sauria, Teiidae) in the grasslands of the Araucaria Plateau, southern Brazil

The reproductive cycle and sexual dimorphism of the lizard Cnemidophorus vacariensis Feltrim & Lema, 2000 were studied on the basis of data gathered between August 2004 and August 2006 in Vacaria, Rio Grande do Sul, Brazil. Snout-vent length (SVL) of sexually mature males varied between 48.8 and 72.9 mm (x = 63.3 ± 6.0 mm; n = 76) and, for females, between 57.4 and 81.8 mm (x = 70.0 ± 5.9 mm; n = 73). Other morphological characteristics were also compared between sexes. Reproduction was seasonal, and observations indicate two clutches in the same reproductive season. Clutch size and other reproductive characteristics were analyzed as well as the relation between reproduction and environmental factors. Cnemidophorus vacariensis is apparently endemic to highland plateaus in southern Brazil and has been classified as vulnerable on some lists of threatened fauna in this country. Some suggestions for conservation measures are presented, due to the observed degradation of this species' environment.

Sexual dimorphism in Amphisbaena nigricauda (Reptilia, Squamata, Amphisbaenidae) from Southeastern Brazil

Amphisbaena nigricauda Gans, 1966 is a small, poorly known amphisbaenid endemic to the restinga of the states of Espírito Santo and Bahia, Brazil. We analyze 178 specimens collected in Vitória municipality, state of Espírito Santo, Brazil, to investigate whether this species show sexual dimorphism in pre-cloacal pores and in morphological characters. Sex was determined by a ventral incision and direct inspection of gonads. A PCA analysis was performed to generate a general body size measurement. A T test and the non-parametric Mann-Whitney test were used to assess whether this species show sexual dimorphism on five morphometric and five meristic characters, respectively. Sex could not be determined in 36 specimens because they were mutilated in the posterior portion of their bodies. The diagnosis of the species is redefined based on this sample size: the smallest number of body annuli changes from 222 to 192, the number of dorsal and ventral segments in an annulus in the middle of the body changes to 9-11/13-16 (instead of 10/16), and the autotomic tail annulus lies between annulus 7-10 (instead of 6-9). The number of tail annuli remained within the known range of variation of the species (19-24). None of the 80 females analyzed showed pre-cloacal pores, whereas within males 59 out of 62 specimens displayed four and two specimens displayed five pre-cloacal pores. A single male did not possess pre-cloacal pores, but showed irregular scales on its cloacal region. Sex-based difference based on presence or absence of pre-cloacal pores as well as males with wider head was seen in other Neotropical amphisbaenids. However, a pattern of body size differences between males and females has not been identified so far in the few amphisbaenid species studied in this regard. Further studies on this taxonomic group are still needed to elucidate the existence of general patterns of sexual dimorphism and to identify the selective pressures driving these patterns.