Efeito do extrato aquoso de folhas de Polymnia sonchifolia (yacon) em ratas diabéticas

Polymnia sonchifolia is a medicinal plant used as hypoglycemic agent and other ends. The aim was to evaluate the yacon effect on diabetes in Wistar female rats, which was divided in 4 groups: non-diabetic (n=24) given (gavage) 32.4 mg kg -1 of an aqueous extract of plant (treated group) or vehicle (non-treated group), and one diabetic group (n=24) with similar treatment compared to non-diabetic rats. Diabetes was induced using streptozotocin (i.v. route, 40 mg kg -1). Glycemia was monitored after rodent adaptation period, 15 days after diabetes induction, and each 10 days after yacon/vehicle in early treatment. During experiment period, body weights, food and water intake were daily measured. The rats (non-diabetic or diabetic) given yacon extract treatment presented no significant difference related with glycemia, body weight gain, and food and water intake. Thus, further studies such increase of rat number in agreement with different glycemic levels and increase of the plant extract dose are necessary.

Estudo morfológico comparativo das cascas e folhas de Stryphnodendron adstringens, S. polyphyllum e S. obovatum - Leguminosae

The genus Stryphnodendron (S.) belongs to the family Leguminosae, subfamily Mimosoideae, which includes mostly trees of tropical and subtropical South America. Extracts of the stem bark are used traditionally by the local population to treat leucorrhoea and diarrhoea, as anti-inflammatory and antiseptic agents (antimicrobial) and to promote blood clotting and wound healing, and in a few cases of gastric ulcers. A review of the literature presented a previous morpho-anatomical study only for S. adstringens (Mart.) Coville. The aim of the present work is to compare morpho-anatomically the stem bark and leaves of three species of Stryphnodendron, known popularly as barbatimão: S. adstringens, S. polyphyllum and S. obovatum, in order to help botanical identification and contribute to quality control. Macro- and microscopical evaluation of the stem barks revealed no significant differences among the species. Morphological analyses of the leaves revealed differences in size, coloration, and pubescence. The leaves of S. adstringens are the largest, glabrous, and concolor. The leaves of S. polyphyllum are smaller, pubescent, and discolor; whereas the leaves of S. obovatum are the same size as those of S. polyphyllum, however, they are glabrous, and discolor.

Toxicidade aguda do sulfato de cobre e do extrato aquoso de folhas secas de nim para o caramujo (Pomacea canaliculata)

Snails can become an environmental and economic problem, causing substantial losses. The objective of this work was to estimate the acute toxicity of copper sulfate pentahydrate (CuSO4.5H2O) and the aqueous extract of dried neem leaves on snails (P. canaliculata) under laboratory conditions. In order to estimate the lethal concentration 50% (LC (I)50;96h), snails were exposed to six increasing copper sulfate concentrations (0.0; 0.01; 0.03; 0.05; 0.07 and 0.1 mg L-1) and six increasing concentrations of aqueous extract of dried neem leaves 0.0; 100; 125; 150; 175 and 200 mL aqueous extract of dried neem leaves L-1 water, equivalent to (0.0; 1.18; 1.47; 1.77; 2.06 and 2.36 mg azadirachtin L -1), in triplicate and one control treatment in an entirely random delineation. Estimated LC (I)50;96h, of copper sulfate was 0.02 mg copper sulfate L-1, with a 0.01 mg L-1 lower limit and a 0.03 mg L-1 upper limit. Estimated lethal concentration 50% of the aqueous extract of dried neem leaves was 142.75 mL L-1, equivalent to 1.68 mg L-1 of azadirachtine, with a 130.89 mL L-1 (1.54 mg L-1) low limit and 155.69 mL L-1 (1.83 mg L -1) as the upper limit.

Atividade anti-micobacteriana de extratos de folhas de Byrsonima crassa Nied

In this study, the antimycobacterial activity of chloroformic and methanolic extracts obtained from Byrsonima crassa leaves was evaluated. Antimycobacterial activity was assessed through the microtechnique named Microplate Alamar Blue Assay (MABA) and the promising active principles were identified by spectrophotometric analysis. The chloroformic extract presenting 62.5 μg mL-1 minimum inhibitory concentration (MIC) showed to be active against tuberculosis bacillus. The MIC value of the methanolic extract was 1000 μg mL-1. For the chloroformic one , phytochemical analysis indicated that antimycobacterial activity might be related to the presence of triterpenes.

rastreamento histoquímico, fitoquímico e biológico de folhas de Plinia cauliflora (DC.) Kausel (Myrtaceae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Doses de Nitrogênio na Produção de rabanete fertirrigado e determinação de clorofila por medidor portátil nas folhas

The relative chlorophyll determination is used to predict the need for nitrogen fertilization aiming to increase production in various cultures. The objective of this study was to evaluate the soil nitrogen dose response added to the soil via fertigation in radish production and the relation between chlorophyll and cultivar Redondo Vermelho leaf nitrogen content. Transverse diameter of root, leaf area, green index, leaf N contents, shoots (stem) production, number of commercial and noncommercial roots, and the total commercial mass roots were evaluated. The N doses didn't interfere in the radish production and the readings taken with portable chlorophyll meter are not very accurate in ascertaining the level of N on radish plant growth.

Sementes de feijão-caupi (Vigna unguiculata L. (Walp), tratadas com extrato de folhas de nim (Azadirachta indica A. Juss.) avaliação da germinação e da incidência de fungos

This study aimed to evaluate the effect of aqueous extract of neem on germination and fungi incidence on seeds of three cultivars (Serrinha, BR 17 and Maranhão) of cowpea. Neem leaves were dryed, crushed and prepared dilutions of 0.5; 1.0; 2.0, 4.0 g dm -3and control. The fungi incidence was evaluated by the test filter paper and germination according to the Rules for Seeds Testing (Regras para Análise de Sementes). In the three cultivars analyzed, reduction in the incidence of Aspergillus sp and Fusarium sp was observed. In relation to the influence of extracts of neem leaves on seed germination, significant effect of extract in Maranhão cultivar was observed, where all concentrations differed from the control, and propovided a considerable increase in the percentage of normal seedlings. It was concluded that the leaf extract of neem was effective in controlling Aspergillus sp, Fusarium sp , Phoma sp and Macrophomina phaseolina at different concentrations in different cultivars and seed germination was stimulated for the Maranhão cultivar.

Dinâmica de cátions na raiz e folhas de berinjela cultivada sobre doses crescentes de potássio oriundas de duas fontes

This study was conducted at the Department of Plant Production, Sector Horticulture, UNESP - Botucatu, SP, Brazil, in order to assess the dynamics of cationic nutrients in roots and leaves and effects on dry matter production of roots and shoots in eggplant grown on conditions of increasing doses of potassium from two distinct sources (KCl and K 2SO 4). The experiment was arranged in randomized blocks in factorial 2 × 4 (two sources of potassium, KCl and K 2SO 4 and four doses of each source equivalent, 250, 500, 750 and 1000 kg ha -1 K 2O) comprising eight treatments with three replicates. For the experiment we used Oxisol medium texture (615 g of sand, silt 45 g and 340 g clay per kg soil). The characteristics evaluated were: soil electrical conductivity, mass of shoot and root material, content and ratio of K +, Ca 2+ and Mg 2+ in roots and leaves of eggplant. We conclude that excessive doses of sources of K 2O affected the production of dry matter of roots and shoots, as well as electrical conductivity. The accumulation and the relationship of Ca2+/K+, Mg 2+/K + were affected by increased K + concentration; K 2SO 4 was the fertilizer that was less damaging.

Efeito de produtos químicos sobre a mancha bacteriana (xanthomonas perforans) e na ativação de proteínas relacionadas à patogênese em tomateiro

The present study aims to evaluate the effect of fungicides and antibiotics to control bacterial spot (Xanthomonas perforans) in tomato, and the activation of pathogenesis-related proteins. Hybrid tomato AP 529 was used to assess the severity of disease. The treatments consisted of spraying with acibenzolar-S-methyl, fluazinam, pyraclostrobin, pyraclostrobin + methiran, copper oxychloride, copper oxychloride and mancozeb + oxytetracycline, and inoculated and non-inoculated controls. After three days of treatment, all plants were inoculated with X. perforans (10 6 CFU / mL). Leaf discs were collected for assessment of peroxidase, polyphenol oxidase, β-1,3 glucanase, phenylalanine ammonia lyase and protease. The area under the disease progress curve (AUDPC) was calculated with the data of severity. All treatments had reduced AUDPC compared to the inoculated control. Fungicides acibenzolar-S-methyl, pyraclostrobin, and pyraclostrobin + methiran had more satisfactory results in reducing the severity of bacterial spot on tomato. The products based on pyraclostrobin together with acibenzolar-S-methyl induced enzymatic activities of peroxidase, polyphenoloxidase and β-1,3 glucanase, indicating that these products may be related to the induction of resistance to bacterial spot on tomato plants.

Controle da mancha angular do feijoeiro com uso de fungicidas e seu efeito na produção das plantas

The angular leaf spot of dry bean caused by the fungus Phaeoisairopsis griseola is a very important disease on dry bean crops in Brazil. In propitious weather conditions, susceptible cultivars have significant losses due to this disease. In these conditions, fungicide usage is an important step for angular leaf spot management. Since the effects of this method of control on plant physiology are not known, this study had the following objectives: a) Verify the action of fungicide in physiological changes in dry beans (photosynthesis rate and stomatal conductivity); b) evaluate the efficacy of some fungicides for the control of angular leaf spot; and c) examine the effects of these fungicides on other agronomic parameters; weight of 100 grains, number of grains per pod and number of pods per plant. The dry bean cultivar used in this study was Perola. Four trials were conducted, two in a net greenhouse and two trials under field conditions. A spray of piraclostrobin, tebuconazol and tebuconazol+ trifloxistrobin increased photosynthesis rates, although stomatal conductivity was not changed. In addition, sprays of tebuconazol, piraclostrobin, metiram+piraclostrobin and azoxistrobin provided better levels of disease control and also higher weight of 100 grains, with the exception of azoxystrobin for this parameter.

Herbivoria em soja: Efeito na composição química das folhas e na biologia da lagarta da soja e do percevejo verde pequeno

The objective of this research was to study the effect of previous herbivory in the chemical composition of soybean leaves, and its influence on Anticarsia gemmatalis (Hüeb.) and Piezodorus guildinii (West.) development. Two soybean genotypes, 'Embrapa 4' and 'BR 37', were chemically analyzed. The caterpillars were fed on these genotypes leaves and the bugs on string beans, both injured and non- injured (control), totalizing 4 treatments with 50 replications for each treatment. Herbivory was performed by releasing 3rd instar velvetbean caterpillar. The caterpillars were taken out when 30%-40% of foliar area were consumed. After that, leaves and string beans were used in the experiment. The results obtained during this research indicate that leaves chemical composition was altered and that, in general, A. gemmatalis larvae and P. guildinii nymph have presented better development when fed on non-injured soybean plants, being 'Embrapa 4' genotype the most efficient one concerning insects development.

Desempenho de fungicidas no controle da mancha-de-macrospora na cultura do milho

Fungicide application is one of the control strategies of fungal diseases in corn leaves. In Brazil, there are no fungicides recorded for the control of corn macrospora leaf spot (MLS). The aim of this study was to assess the efficacy of 16 fungicides on MLS control in a protective, curative and eradicant form. Fungicides of the chemical groups of benzimidazoles, strobilurins and triazoles were used alone or in mixture, in completely randomized block design, with six replicates of five plants, totaling 30 plants per treatment. The experiments were carried out in a greenhouse with the single-cross hybrid AS 1565 in phenological stage of two to six expanded leaves, using an isolate of S. macrospsora from the same hybrid. The inoculum was deposited into the cartridge of plants at 48 hours after, 48 hours before and 10 days before fungicide applications for preventive, curative and eradicant action, respectively. The experiment was repeated twice. The data underwent analysis of variance (p<0.05), and the means of treatments were compared by using the Scott-Knott test (p<0.05). Severity was estimated at 21 days after inoculations. All fungicides significantly differed from the control treatment in the preventive, curative and eradicant action. For the preventive action, mean disease control was 85%. The mixture of triazoles plus strobilurins controlled, on average, 75% of the disease severity, while the isolated products such as strobilurins reduced it by 62%, benzimidazoles by 55% and triazoles by 38% for the curative action. The lowest control was obtained for the eradicant action, with mean reduction of 40.1% in the disease severity and no significant difference among fungicides.

Folhas de amoreira tratadas com vitamina e esterol e seus efeitos em parâmetros biológicos de Bombyx mori L.

This study aimed to evaluate the effects of adding different concentrations of the leaf additives nandrolone decanoate, ascorbic acid, retinol palmitate and retinol acetate on biological parameters of Bombyx mori larvae. The results showed that nandrolone and ascorbic acid, both at 0.5%, provide the best value for the development of the larvae of B. mori, values which do not correspond to significant increases in cocoon and silk production; 1.0% of retinol palmitate show negative effect to larvae development.

Concentração letal LC50 do extrato aquoso de folhas de terminalia catappa em guaru, phalloceros caudimaculatus

This trial was conducted in order to determine the 50% lethal concentration (LC (I) 50-96h) of the aqueous extract of dried leaves of Terminalia catappa, a plant with antifungal, antibacterial and antiparasitic activity. Due to the increasing use of herbal medicines in aquaculture, its use is an option for controlling diseases in fish. Toxicity tests are important before recommending any treatment, since some products have therapeutic concentration close to lethal. To conduct the study used 135 fish species Guarus (Phalloceros caudimaculatus), exposed to increasing concentrations of: 0.0, 50.0, 100.0, 150.0, 200.0, 250.0, 300.0 mL of stock solution per liter of water. The results were calculated by the method Trimmed Spearman Karbo, demonstrating that the 50% lethal concentration (LC (I) 50-96h) estimated was 208.52 mL / L, with lower limit of 187.79 mL / L and higher 231.54 mL / L. Observed changes in behavior of the test organisms at concentrations above 250 mL / L decrease in the levels of dissolved oxygen and pH. Concentrations below 250 mL /L result in mortality rate near zero, so the aqueous extract shown low toxicity.

Escala diagramática para quantificação da severidade de manchas em folhas de Eucalyptus globulus Labill. causadas por Teratosphaeria nubilosa (Cooke) Crous & U. Braun

The leaf spot (Mycosphaerella leaf disease = MLD) caused by Teratosphaeria nubilosa has caused damage in eucalypt plantations in southern and southeastern Brazil. The need to assess the disease in the field to evaluate of this damage, efficiency control, evaluation of germplasm induces to the necessity of having a visual scale for evaluation of disease. The objective was to develop a diagrammatic scale for young leaves and one for adult leaves of Eucalyptus globules for MLD. To do so, the leaves collected in the field were scanned for image analysis. The damaged area, the healthy leaf area and the external area of the same scale RGB (Red, Green, Blue) were determined. Subsequently, it was determinate the levels of severity depending on the sample distribution with seven levels for young leaves and six for adult leaves. For the visual acuity test and validate the scale, the leaves were evaluated for severity, with and without scale. With this proposed scales, the assessors showed good accuracy both for young and adult leaves with R2=0,98 and R2=0,80, respectively. The importance of the development of diagrammatic scales for assessing MLD in eucalyptus must to the fact that allows quantification of the symptoms accurately and precisely.