The use of pioneer plants, mainly nitrogen-fixing leguminous trees, associated to the secondary and climax species, has been making possible good results in the land reclamation. However, it is important to establish the appropriate spacing among the form species obtaining a fast covering and protection of the soil, without there is strong competition of the plants for light, water and nutrients. So, the objective of this work was to evaluate the growth of the Hymenaea courbaril and leguminous trees at, in system quincux, in different spacings. The treatments, in factorial scheme 3 x 3 with three replicates, corresponded to three species of pioneer leguminous trees (Acacia mangium, Senna multijuga and Leucaena leucocephala combined with Hymenaea courbaril) and three spacings among pioneer plants (4 x 2; 4 x 3 and 4 x 4 m). After one and two years of planting determined the height, stem diameter at ground level and crown diameter of pioneer plants and Hymenaea courbaril. Acacia mangium showed growth characteristics superior to those of Senna multijuga and Leucaena leucocephala, however, no influence of spacing between species in relation to these characteristics. The growth characteristics of the Hymenaea courbaril were not influenced by pioneer species associated, however, the denser spacing between the pioneer species favored the greatest increase.

This work deals with the survey of the family Acanthaceae in the region of Xingó, in the States of Alagoas and Sergipe. Five species belonging to three genera were found: Anisacanthus trilobus Lindau, Justicia aequilabris (Nees) Lindau, Ruellia asperula (Mart. ex Nees) Lindau, R. bahiensis (Ness) Morong and R. paniculata L. Descriptions, illustrations, comments about geographic distribution and key to the recognition of the taxa are provided.

The purpose of this study was to evaluate the effects of weed interference with Brachiaria brizantha pasture establishment and regrowth after cutting. Two experiments were conducted simultaneously in randomized complete blocks with four replications. In the first test, forage was grown together with weeds for 0; 7; 14; 21; 28; 35; 42; 49; 56, and 63 days after forage emergence (DAE) and in the second, the forage was maintained weed-free for the same periods. The weed population was evaluated during coexistence period between weeds and forage crop. The forage yield and leaf / stem ratio of B. brizantha were evaluated after forage cutting (63 DAE), and 119 and 289 DAE. Weed growth was strong in coexistence with B. brizantha during pasture formation, causing a reduction in forage yield. The period considered critical in the competition between the weed and forage community lasted from 9 to 26 DAE. However, there were also significant effects on the regrowth of B.brizantha after the second forage cut, in the dry season, showing that pasture recovery after cutting was prejudiced by the competing weeds during the pasture establishment. The competition did not affect the photoassimilate partitioning between leaves and stems in the forage plant.

The objective of this study was to evaluate the utilization effects of two native cacti named mandacaru (Cereus jamacaru DC.) and xiquexique [Pilosocereus gounellei (A. Weber ex K. Schum.) Bly ex Rowl.] associated with sabiá (Mimosa caesalpiniifolia Benth.) and flor de seda (Calotropis procera (Ait.) R.Br.) about the nutrient intake, daily weight gain, and feed conversion in sheep feedlot. Twenty Morada Nova male hair sheep with an average weight of 15.40, were allocated in a randomized block design, with four treatments and five replicates. The experimental treatments consisted of four diets (30% native cacti + 30% shrub hay + 40% concentrate, on dry matter basis): T1- xiquexique + sabiá hay; T2- xiquexique + flor de seda hay; T3- mandacaru + sabiá hay e T4- mandacaru + flor-de-seda hay. The concentrate consisted of 100.0% algaroba (Prosopis juliflora (Sw) DC) pods. No significant difference was observed for daily weight gain which averaged 88.77 g, and also for voluntary intakes of dry matter, organic matter, ether extract, total carbohydrates, nonfiber carbohydrates, total digestible nutrients and digestible energy in relation to g/day, %BW and g/kg0.75. Significant differences were observed for intake of water in g/day.

The objective of present work was of classifying, consonant the Brazilian System, profiles of soils of ecosystems, as subsidies to evaluation of soil quality. The fieldwork was driven at the place Chã de Jardim, municipal district of Areia, PB, Brazil. They were open trenches, in different agrosystems - sabiá population (T1), of pinus (T2), and traditional cultivation-degraded area (T3), where they were made the description and it collects of soil materials for accomplishment of the chemical and physical analyses. The soils were classified in the Brazilian System of Classification of Soils. Being adopted an operational sequence, the profiles of respective areas were classified as: Entisol, Oxisol and Inceptisol In terms of quality of soil and starting from an arbitrated minimum indication, it was verified that profiles under pinus population and sabiá have position privileged in relation to degraded area. In spite of drop reservation of nutrients of profiles (dystrophic), the recycling in the soil under leguminous (T1) it is more efficient, since the reservation of nutrients in the Entisol is smallest among the compared sub superficiality.

This study was aimed to carried out a floristic survey in four communities that are localized in the São Miguel do Gostoso municipality - RN, focusing on the Leguminosae species and its potential use. Field research was carried out between May and October/2007, for acquire information about the use of plants and samples of them in the local communities. The study registered 102 species pertaining 73 genera and 30 families. Leguminosae/Fabaceae (25), Asteraceae (10) and Euphorbiaceae (8) were the most representative families in number of species and the genus Mimosa L. and Senna Mill., with five species each. Most species of Leguminosae (68%) have economic value and are recognized seven categories of use: medicinal (8), technology (7) fuel (8), construction (6), fodder (14), veterinary (2) and other (9). Although many species have different types of utilities, Poincianella pyramidalis (Tul.) L.P.Queiroz stood out from others by being quoted in all use categories considered.

The accelerated process of environmental degradation in the São Francisco Drainage Basin (BHSF) has generated a high demand for seeds destined to the production of plant propagules. However there is no information about the commercial value of the diaspores of forest species which occur in the BHSF. The objective of this study is to propose a system to evaluate the worthiness of the kilogram of seeds for 22 plant species of the Caatinga, based in the following parameters: geographic distribution, endemism, level of threat, functional group, processing, collection effort, classification of seeds and number of seeds per kilogram. Field studies were conducted in five municipalities of the the region of the central valley of the São Francisco River and on five islands located in the main channel of the São Francisco River, from August 2007 to September 2008. The prices calculated using our system varied from R$ 10.00 for Syagrus coronata Mart. Becc. (Arecaceae) and R$ 44.15 for Handroanthus spongiosus (Rizzini) S.O.Grose (Bignoniaceae). From a 50% cut percentage in a cluster multivariate analysis we identified the occurrence of three groups: a group with seeds of lesser commercial value (average value of R$ 18.80.Kg-1), a second group with intermediate commercial value (R$ 28.21.Kg-1) and a third group with seeds of higher commercial value (R$ 32.85.Kg-1). We hope that this study will contribute to the process of conservation and ecological restoration of Caatinga, and also to the improvement of the socio-economic conditions of the local population from the commercialization of these seeds.

This work aimed to evaluate the effect of cut height on jurema-preta control. Thus, two trials were carried out, one in September 15th and other in December 15th of 1997. The experimental area had 1,400 m². Treatments were the height cuts of 25; 50; 75 and 100 cm from the soil. Evaluations were done when more than half of plants were showing 50% of their regrowth with a diameter of 0.7 cm. The experimental design was in randomized blocks with split-plot, being the height cut the parcel and the cut the sub-parcel. In the first trial and at the end of the 3rd cut, the higher mortality of 84.6% was found among plants cut at 75 cm and the higher number of regrowth was observed in plants cut at 100 cm, but the stem diameter was not affected by treatments. In the second trial and at the end of the 3rd cut, the higher mortality of 50% was found among plants cut at 100 cm and the other variables were not affected by cut height. The control of jurema-preta may be done in September, cutting the plants at 75 or 100 cm from the soil and always cutting the regrowth plants when they reach 0.7 cm of diameter. The jurema-preta control by standardization cut in December was inefficient regardless the cut height.

Phylogeography has become a powerful approach for elucidating contemporary geographical patterns of evolutionary subdivision within species and species complexes. The aim of this paper was to evaluate the extracted quality of DNA and amplification of noncoding chloroplast DNA for phylogeography studies in Ficus bonijesulapens. The comparative analysis of protocol DNA extraction was based in the CTAB method and protocol from Mogg and Bond. DNA samples were assessed for successful PCR amplification of universal primers for the amplification of noncoding regions of cpDNA. Amplified DNA was separated by electrophoresis, stained with ethidium bromide and photographed under UV light. The protocol Moog e Bond produced the best DNA quality. This method will be used because it produces a high quality DNA in a short time and is less expensive. The primers HA, SG, BF, Q16, F32, FV, DT, CS and JA provided the strongest support for the inferred phylogeography, genetic diversity centers and for successful management in tree-conservation programmes.

Lettuce has highlight as an important crop for human consumption, to having good flavor and important nutritional characteristics and potassium is one of the main nutrients that crop. This work aimed to evaluate the influence of potassium in morphological and physiological lettuce responses in South of Tocantins State. The experimental design was randomized block in factorial scheme of 4 x 6 with three replications. Four levels were evaluated of K2O: 0; 100; 200 and 300 kg ha-1 in six development stages: 15; 22; 29; 36; 43 and 50 days after emergency. Was determine the specific leaf area, net assimilation rate, relative growth rate and abso-lute growth rate, as well as the leaf, stem and root weight. During the duration of the experiment occurred high temperatures that caused a physiological disorder known as tipburn, which compromises calcium uptake by the plant. The potassium levels did not influence the morphological and physiological responses of lettuce as well did not significant differences among levels for leaf, stem and root weight. The partition of assimilates in the plants was influenced by crop management whit significant variation among evaluation times.