Considering the importance of studies in communities dynamics, especially in vegetation sites with anthropogenic disturbs as Caatinga of Northeastern Brazil, was evaluate the edge effect caused by the opening of a oil duct on the dynamics of plants in three physiognomies of Caatinga (open shrub, riparian shrub dense and shrub dense) over 15 months (May/2007, January/2008 and August/2008), taking into account the hypothesis that there are differences in the dynamics in areas near edge and more distant. In each situations were evaluated edge and interior, so much in terms of trees in five plots of 10×10 m contiguous as of regeneration of the plants in plots of 2×2 m. Were calculate mortality, recruitment and growth rates in the edge and interior. Most important differences in terms of edge and interior occurred in open shrub Caatinga. The largest fluctuations in the values of density and diameter occurred at the edge, which indicates that the opening of the duct caused greater interference in this situation.

The aim of this research was to examine the response of utilization of wastewater and organic manure on the growth of sunflower (Helianthus annuus L. cv. Embrapa BRS Oásis). The study was carried out from April to July 2009 in a greenhouse. Sunflower plants were irrigated with wastewater and tap water combined with doses of humus (w/w) of 0.5, 1.0, 1.5 and 2.0% and two controls (wastewater + mineral NPK and tap water + NPK) with three replications. Humus application did not show significant effect on any variable analyzed except duration of post-harvest where all treatments presented duration more than the established by the market, while the wastewater was efficient in all assessments, promoting substantial increases in the growth of sunflower.

Some physical and chemical characteristics of Mimosa caesalpiniaefolia Benth. wood were analyzed in order to study its potentiality as alternative specie to produce tannins. The polyphenols (tannins) were avaliated by Stiasny reaction. The wood from this specie showed an average of 41.1% and 58.9% for heartwood and sapwood respectively. The average quantity of extracts was 9.0%. The contents of cellulose, hemicellulose and lignin were 32.8%, 33.2% and 24.6% respectively. The averages of polyphenols (Stiasny index) for heartwood and sapwood, were 96% and 42% respectively. The highest tanni ns content was in the heartwood with content of 11.5%. The results showed that is possible to use Mimosa caesalpiniaefolia as a source of condensed tannins.

The aim of this work was to evaluate methods for overcoming Jitirana's (Merremia cissoides) seeds dormancy. The treatments were: immersion of Jitirana's seeds in sulfuric acid during 20, 25, 30, 35, 40, 45, 50, 55 and 60 minutes and control (no treatment). The experiment was carried out in the completely randomized design, with ten treatments and four replications, with 20 seeds each. The variables evaluated were: germination percentage, germination speed index, medium time for germination, dry weight and height of seedling obtained 16 days after sowing. The immersion of seeds in sulfuric acid during 50 minutes is an efficient method to overcome dormancy and promotes germination, enabling quickly and greater Jitirana's seedling emergence.

The purpose of this study was to evaluate the effect of diazotrophic bacteria inoculation and nitrogen fertilization on grain yield and nitrogen accumulation in rice plants. We used seeds of rice cultivars IR42 and IAC4440, which were inoculated with peat containing the strains ZAE94 (BR 11417 - Herbaspirillum seropedicae) and M130 (BR 11340 - Burkholderia sp.). We used the first 20 cm of an Albaqualf Ecological Series. The experiment was conducted in a completely randomized design with four replications and four plants per pot. We applied three levels of nitrogen (0, 50 and 100 kg N ha--1) and evaluated the parameters of shoot dry weight, nitrogen accumulation in shoots and grains, in addition to grain yield and the quantification of population of diazotrophic plants. Positive effects of inoculation were observed in both cultivars studied in all parameters evaluated, mainly in the accumulation of nitrogen in plants and grains.

Mycorrhizal fungi has been shown to affect some species of parasitic nematodes, in many cases reducing oviposition and the number of galls on the root system of infected plants. In order to evaluate the biocontrol potential of arbuscular mycorrhizal fungi to reduce the infectivity of Meloidogyne incognita in tomato plants, an experiment was conducted with a randomized block design with eight replications in a factorial with thefollowing treatments: with and without M . incognita, with presence and absence of fungal species Glomus clarum Nicolson & Schenck, Gigaspora albida Schanck & amp; Smith and Acaulospora scrobiculata Trappe. The fungus G. clarum significantly reduced the gall index (46.4%) and the number of egg mass (78.8%) of the nematode on tomato seedlings. The percentage of root colonization is not in itself an indicator of efficiency in controlling fungal infectivity of M. incognita in tomato plants, since A. scrobiculata exhibited a high degree of colonization (77.6%) and was not effective in controlling nematode reproduction. The species of mycorrhizal fungi differ in efficiency in reducing the infectivity of M. incognita in tomato seedlings.

This work evaluated the effect of two methods of determination of soil water (laboratory method and field method) and four levels of soil water availability (20; 40; 60 and 80%) on biomass of the aerial part, crop evapotranspiration, leaf area, plant height and yield in pit of herbaceous cotton plant, cultivar CNPA-7H. The randomized blocks experimental design was used in factorial scheme 2 x 4, with three replications. The determination of available soil water by the field method overcame the results of the studied variables in relation to the laboratory method and it represents more real conditions of the readiness of water for the cotton plant. The leaf area and the evapotranspiration, determined by field method, increased significantly with the levels of available soil water. The management with the available water of 61.61% by laboratory method promoted the maximum leaf area of 1755.4 cm2 and, with 74.4% of levels of available water, the maximum evapotranspiration was of 238 mm. There were earnings of 0.2 g of biomass per unit of levels of available soil water by field method; already by laboratory method the maximum biomass of 17.6 g was reached with the management of levels of available water of 62.9%. The best response for the cotton incomes in pit was given by field method with earnings in the income of 0.26 g for the field method and of 0.11 g for the laboratory method per unit of available soil water.

The aim of this work was to evaluate some empirical equations performance used to estimate the evapotranspiration of reference in relation to the standard method Penman-Monteith FAO - 56 for the climatic conditions of the city of Eunápolis - BA. Climatic variables were used as referrals to the years of 2006 to 2007 obtained through the automatic platform collection of data from Hydrical Resources Superintendency of Bahia / National Institute for Space Research, where it was obtained the average for two years. In order to compare the values of ET0 estimated by empirical equations with the standard method Penman-Monteith (FAO 56), were considered the parameters of the regression equation (a and b), the coefficient of determination (r²), coefficient correlation c, estimate of the standard err (EEP), index of agreement (d), index of confidence or performance c, in the scales of one, three, five and seven days. The results obtained from this study reveal that the Hargreaves-Samani method overestimated the ET0 in 23% characterizing it as the less method to estimate it. The methods of Radiation and Blaney-Criddle satisfactorily met the estimate of ET0 for the climatic condition on the studied region.

Bactris gasipaes is an important Amazonian culture as the main source of hearts of palm. Techniques of plant tissue culture are promising tools in breeding programs of this culture. The objective of this study was to develop protocols for the in vitro establishment and callus induction in Bactris gasipaes shoot tips. Shoots were collected from young plantlets of B. gasipaes, which were disinfected with NaOCl 0.63, 1.25 and 1.88% (v/v), for 10, 20 and 30 minutes. After that, shoot tips were removed and inoculated in MS medium with factorial combinations of the growth regulators 2,4-D (0.0; 5.0; 10.0; 20.0 and 40.0 mg.L-1) and BA (0.0; 3.0 and 6.0 mg.L-1). The experimental design was entirely randomized, replicated three times with ten tubes containing one explant per plot. The disinfection was efficient for 20 minutes of immersion in NaOCl 1.25%, which resulted in 90% of explants without contamination and low oxidation. The greater callogenesis percentage was of 60%, reached at 10.0 mg.L-1 2,4-D and 3.0 mg.L-1 BA combination.

The purpose of this research was to make a floristic survey of the shrubby-arboreous stratum in three contiguous areas of Caatinga in the Cariri of Paraiba. The survey was accomplished in the "Estação Experimental Bacia Escola/UFPB", municipality of São João do Cariri, PB Brazilian Northeast. The experiment consisted of three areas of 3.2 ha, where three parallel transects had been established, in a distance of 20 m from each other, and there were marked ten parcels with equidistant systematic distribution (10 m x 10 m), having been sampled 30 parcels from each area. The floristic survey was carried through by the method of parcels. There was fulfilled a grouping analysis using the index of similarity of Jaccard. The number of parcels showed was enough to reflect the plantdiversity of the studied places; the families with highest number of species in the arboreous-shrubby stratum were Cactaceae and Euphorbiaceae; the species that had been common in the three areas, , were: Aspidosperma pyrifolium, Croton blanchetianus, Poincianella pyramidalis, Jatropha mollisssima, Malva sp., Pilosocereus gounellei, Spondias tuberosa and Opuntia palmadora. The arboreous habitat presented seven species, being higher to the shrubby component that was presented with five species. The more conspicuous arboreous elements had been: Poincianella pyramidalis (Caesalpiniaceae) and Aspidosperma pyrifolium (Apocynaceae). The most important shrubs were: Croton blanchetianus and Jatropha mollisssima (Euphorbiaceae). The analysis made by the index of floristic similarity indicated that the similarity was considered high by the three area, because they presented a Jaccard index higher than 0.25.