Several microorganisms produce polysaccharides, deemed to protect the bacteria from several environmental stresses. This paper aims to evaluate the protective effect of exopolyssacharides to different abi- otic stresses in bacterial isolates from “sabiá” ( Mimosa caesalpiniifolia ) nodules. 303 fast growing isolates were qualitatively evaluated for exopolyssacharide production and tested in vitro for tolerance to two levels of acidity, joint aluminum and acidity, three salinity levels; 11 antibiotics and three herbicides. Most isolates re- sisted media acidity, acidity with aluminum, salinity, and ampicillin, cefotaxime, gentamicin and vancomycin antibiotics and 2,4D herbicide, while being sensitive to ciprofloxacin, chloramphenicol, streptomycin, kanamy- cin, nalidixic acid, rifampicin and tetracycline antibiotics and paraquat and glyphosate herbicides. There was no connection between exopolyssacharide production and abiotic stress tolerance.

The objective was to evaluate the effect of the omission of macronutrient and micronutrient boron in dry matter production, the characterization of the symptoms of nutritional deficiencies and mineral composition in plants of ipeca, an experiment was conducted in greenhouse conditions by the technique the missing element and visual diagnosis. A randomized block experimental design with four repetitions and the treatments were: complete and omissions of N, P, K, Ca, Mg, S and B. The analytical results demonstrated that the production of dry matter was affected in all of the treatments with omission of nutrients and that the ipeca plants presented characteristic symptoms of nutritional deficiencies due to the omissions of N, P, K, Ca, Mg, S and B and the concentrations of the macronutrients and of the micronutrient boron in the different parts of the ipeca plant varied when a certain nutrient was omitted in the solution.

With purpose of evaluating the salinity’s effe cts of the nutrient solution at different stages of development of the culture of pepper grown in a hyd roponic system, an experiment was conducted in a pr o- tected environment at the Department of Environment al Sciences, Federal University of the Semi - Arid (UFERSA). The experimental design was completely ra ndomized design with 15 treatments and three replic a- tions. The treatments consisted of five levels of s alinity of the nutrient solution (1.2, 3.49, 5.69, 7.07 and 9.23 dS m -1 ), applied at three stages of crop development (24, 85 and 120 days after the transplanting) .The leve ls salt obtained by mixing two sources of water (water supply (AB) and waste water desalination (RD)) .Th e nu- tritive’s solution salinity above 1,2 dS m -1 reduced the growth and yield of pepper grown in c oconut fiber sub- strate. The nutrient solutions prepared with water saline waste can be used in the pepper’s grown nutr ition in coconut fiber substrate with the lowest yield loss for increment the electrical conductivities (CEs), when ap- plied at 85 and 120 days after the transplanting , corresponding to fruiting phase.

The crisphead lettuce is a greenery adapted to grow in regions with mild temperatures and lack of rain. The objective of this work was to evaluate the performance of crispheadlettuce cultivars (Del ícia, Teresa, Lucy Brown, Raider Plus, Mauren, Angelin), under tropical climate in city Cáceres-MT, in two h arvest times.The experiment followed the randomized comple te block , with four replications, were arranged in 6 x 2 factorial, being, six cultivars in the crisphead le ttuce and two harvest time. Was evaluated the total and com- mercial production, commercial dry matter mass, com pactness, plant diameter, “head” diameter, health a nd was estimated the proportion of stem in the “head”. The cultivars Teresa and Delícia exhibit the total pro duction upper in relationship the other cultivars evaluated in the experiment, with productions of 631.1 and 5 89.3 g plant -1 , respectively. The second harvest, at large, has w as upper in relationship first, with 607 g plant -1 . The cultivar Teresa, in the second harvest, exhibit the upper result from the commercial production with 4 79.6 and 483.6 g plant -1 , in the first and second harvest, respectively. Th e cultivar Teresa, in the second harvest, exhibit the upper evaluate from compactness. The cultivars Teresa and Delícia were the most suitable for culti vation from weather of Cáceres - MT, and the harvested mus t be performed at 67 days after sowing.

The aim of this study was to identify the main cat egories of use of native plants in a rural com- munity from Caicó Municipality, Rio Grande do Norte , Northeastern Brazil. From March 2007 to August 20 08 semi-structured and structured interviews were cond ucted with 23 local specialists (woodsmen, witch do ctors, healers, growers and housewives) aged over 35. We d escribe the uses of 69 species grouped in seven cat egories which are: medicinal, food, wood, mystic , fuel, fo dder and household. The families with the largest r epresenta- tion in the interviews were Fabaceae (14 species), Euphorbiaceae (6 species), Cucurbitaceae and Cactac eae (3 species each). By calculating the value in use, it was found that Amburana cearensis (Allemão) A. C. Sm. (cumaru) and Mimosa tenuiflora (Willd.) Poir. (jurema preta) stood out as the spe cies with the highest number of citations and nominated uses. The medicinal use was related to 62 species (89.85 %). Barks and root s were the most consumed parts. The data indicate that the flora of the Potiguar Seridó has a great potential of use and that this community will often use local plant reso urces in their everyday life, for many different pu rposes. Keywords : Caatinga. Ethnobotany. Phytoterapy. Northeastern of Brazil.

Ziziphus joazeiro es un árbol fructífero endémico del bioma Caatinga, situada en la región semi- árida del noreste brasileño. No obstante su amplia importancia económica y ecológica, las informaciones sobre la comunidad de insectos asociados a esa especie vegetal son insuficientes. Así, el objetivo de este trabajo fue realizar un levantamiento de los insectos asociados a las flores de Z. joazeiro y observar el horario donde ocurre el mayor número de visitas. El estudio fue realizado dentro del bosque de Z. joazeiro ubicado en el Campus de la “Universidade Federal Rural do Semi-Árido”, municipio de Mossoró, Estado de Rio Grande do Norte, Brasil. El muestreo fue efectuado durante el pico de floración entre los meses de noviembre y diciembre de 2010. Una vez por semana se observaron cuatro árboles de Z. joazeiro, al acaso, desde las 05:00 hasta las 17:00 horas. Cada árbol fue observado durante 15 minutos y los insectos capturados con red entomológica. Los insectos asociados a Z. joazeiro pertenecen al orden Hymenoptera, representados por las familias Apidae, Vespidae, Crabronidae y Leucospidae y, al orden Diptera, con las familias Syrphidae, Muscidae, Calliphoridae, Tabanidae, Dolichopodidae, Stratiomydae, Otitidae y Micropezidae. De todas las familias, Apidae, específicamente, Apis mellifera L., fue la que tuvo mayor frecuencia de visitas, con 48%, seguidas por Vespidae (31.4%) y Syrphidae (9%). En general, los insectos visitaron las flores de Z. joazeiro en mayor frecuencia durante el período matutino, con picos entre las 7:00 y 8:00 horas y entre las 11:00 y las 12:00 horas del día.

This work aimed to evaluate strategies for weed management on the quality of watermelon in the subsequent growing melons in no-tillage (NT) and conventional (SPC). The experiment was conducted in split plot in randomized block design with four replications. The plots were evaluated both tillage systems (no tillage and conventional tillage) and sub-plots, nine strategies for weed management (covering with polyethylene film, with weeding at 14 days after transplanting (DAT) at 14 and DAT 28, 14 and 42 DAT, at 14, 28 and 42 DAT, the DAT 28, at 28 and 42 DAT, the DAT 42 and a control without weeding). We evaluated density and weed dry weight at 14, 28 and 42 DAT and at harvest of watermelon (80 DAT). For watermelon, were evaluated for fruit quality characteristics (longitudinal and transverse length, pulp thickness, firmness, pH and soluble solids). The SPD reduced the density and dry mass of weeds, requiring the completion of only one weeding between 28 and 42 DAT, whereas the SPC was necessary to carry out weeding at 14 and 28 DAT. The SPD and the polyethylene film in the conventional tillage system allow the realization a second crop in the area in succession to the melon, reducing weed interference and providing satisfactory results in the quality characteristics of watermelon.

This study had the objective to evaluate the action of aqueous (EAC), ethanolic (EEC) and decoction (EDC) extracts of juremapreta bark Mimosa tenuifloraand aqueousroot extract (EAR) on the control of alternaria black spot on watermelon, as well as evaluating the mode of action of these extracts, either by presenting toxicity to the pathogen and the ability to alter the metabolism of the host by activating protective enzymes. M.tenuiflora extracts were tested for inhibition of germination, mycelial growth and sporulation of A.cucumerina in vitro. Under controlled conditions (in vivo), the plants were sprayed with the four extracts in three concentrations (05, 4.0 and 10 mg.mL-1) 48 hours before inoculation. The evaluations were based on disease severity and determination of enzymatic activity. In the field the four extracts were sprayed at two concentrations (4.0 and 10 mg.mL-1), evaluating the severity of the disease with the help of descriptive scale. The EAC inhibited 100% germination, mycelial growth and sporulation of A.cucumerina in vitro. The EAC induced synthesis of β-1,3 glucanase and peroxidase, reducing 97% of the disease, in a controlled environment and 31% in the field, being superior to the other extracts and commercial fungicides: copper oxychloride which controlled 79% and 21% for environmental controlled and field respectively, and tebuconazole + trifloxystrobin which controlled 15% in the field. These extracts showed potential to control alternaria leaf spot is caused toxicity to the pathogen or by inducing resistance.

This study aimed at assessing the influence of different seasons of the year (dry and rainy) on urea nitrogen (MUN) concentration of buffalo milk in a commercial herd from Rio Grande do Norte state. The region is characterized by a rainy tropical climate with a dry and wet season from August to January and February to July, respectively. Samples were collected monthly from the cooling tank between February 2010 and February 2011, in the morning. Next, they were homogenized and packed in 40-mL plastic flasks, containing the preservative Bronopol® and later sent to the laboratory for urea nitrogen analysis. Although March 2010 exhibited greater ureanitrogen concentration (25.4 ± 4.4 mg/dL) and November the lowest mean (12 ± 0.4 mg/ dL), there was no significant variation in milk urea nitrogen in samples collected from cooling tanks during the rainy and dry seasons.

The cassava flour is a product known in the Brazil as part of daily meals of the population, mainly in northern and northeastern country. Much of this product is processed by hand, making it difficult to standardize the heterogeneity mainly from the manufacturing processes themselves. In this sense, the physical and chemical attributes of handmade cassava flour sold in Acre, the levels of the Brazilian legislation, were to evaluate. Samples of 20 brands of handmade cassava flour were collected from commercial establishments in Rio Branco, Acre, classified and analyzed for nutrient composition. The results that the flours analyzed, classi- fied as Group Thick and low acidity, are in accordance with the legislation limits for moisture content and starch, but only 10% to be consistent with the actual classification. 25% of the samples were disqualified and 75% were classified as "out of type", which implies that the flour trade of Rio Branco are not in accordance with the standards of the current Brazilian legislation.