The anthracnose is important disease in the pre an d postharvest phases. Several species of Colle- totrichum ( C. gloeosporioides, C. acutatum, C. musae e C. magn a ) are responsible for inciting this disease. The pathogen infects many fruit trees in tropical and t emperate regions, causing considerable damage and l oss in all phases of cultures. Characteristic symptoms are dar k necrotic lesions depressed, subcircular or angula r shaped, and there may be coalescing. Infections have a spec ial feature: the phenomenon of quiescence. This pro cess has important implications, particularly in post-harves t, because the damage from infections reflect only this phase. The intensity of the disease have been striking at temperatures from 24 to 28 °C and in the presence o f high relative humidity. The understanding of some aspect s of the biology of the pathogen (the process of qu ies- cence) and the epidemiology of the disease is cruci al, since much has not yet been fully clarified, es pecially when the aim is to achieve sustainable management.

The adoption of management practices that reduce water losses is essential to conserve moisture and improve soil temperature, especially in arid and semiarid environments of the Brazilian Northeast, characterized by high evapotranspiration and the adoption of irrigation with saline water, which harms growth and yield of commercial crops. Given these factories, an experiment was conducted in Nova Floresta, Paraíba, from August 2010 to February 2011 in Oxisoil, in order to evaluate the production of bell pepper and soil moisture in grooves with side trim, and application of biofertilizer and mulch cattle. The experimental design was randomized blocks with four replications using a factorial 2 x 2 x 2 for the ground beef with and without biofertilizer, with and without residues of sisal fiber (Agave sisalana), with and without the side facing the grooves, to reduce lateral water losses by infiltration of water with polyethylene plastic film. From the results, the lining of the lateral grooves provided higher values of soil moisture, number of fruits, fruit mass, plant production and productivity, bell pepper plants. It was also found that the combination of biofertilizer and mulch the ground beef remained wetter in the first 15 cm depth.

The vegetation of the Caatinga has different types of unique landscapes, in which little is known. Considering the situation, this study aimed to perform a phytosociological survey in area of Ca atinga, located in Bom Jesus, Piauí. Were systematically re leased 15 quadratic plots with 400 m², with spacing of 80 m between plots and between lines. Within each sampli ng unit were measured all individuals with circumfe rence at breast height (CBH) ≥ 6 cm, as measured in these individuals the CBH and the total height. With this, it were calculated the phytosociological parameters, diamet er distribution and diversity index of Shannon-Wean er (H'). In this survey we sampled 640 individuals represent ing 36 species, which provided a density of 1600 in d ha -1 and an estimated basal area of 17.02 m² ha -1 . The species most representatives were Copaifera langsdorffi Desf., Ptyrocarpa moniliformis Benth., Pterodon abruptus (Moric.) Benth and Combretum glaucocarpum (Mart.) Eichl. , with about 43% of the sampled and 40% in the area of ecological importance. The result of the diversity index of Shannon-Weaner was 2.96 nats in d -1 .

The carnauba (Copernicia prunifera (Miller) HE Moore) is a native fruit species to the north- east of Brazil and its exploration is based mainly on the extract of wax powder from leaves. The objective of this study was to evaluate the effect of different management strategies of cutting leaves, developmental stages and leaf age on leaf traits and physical-chemical attributes of carnauba wax in a natural population of carnauba palm located at the Cajazeira Farm, municipality of União, Piauí state, Brazil. The selected plants were identi- fied and classified in two developmental stages: capoteiro and adult palm. The management strategies cutting leaves were: one cut in August; two cuts, the first in August and the second in December; and one cut in De- cember. The leaves were separated according to age into new and old leaf. It was performed the individual analysis of variance of leaf number (LN), wax powder production (WP), ratio WP/LN, moisture content, impu- rities content and wax yield for each management systems as well as the analysis of the different managements. Leaf age presented as the attribute of greater relevance in the commercial use of carnauba. The best manage- ment strategy for cutting leaves of carnauba consists of a single annual cut in December.

Our objective was to evaluate the chemical composit ion and in vitro digestibility of dry matter of hydrolyzed sugar cane in different storage times . We conducted the trial in the Forage Sector at UN IFENAS, campus of Alfenas (MG) in 2010. The data were analy zed as completely randomized design in factorial sc heme 2 (sugar cane without lime and hydrolyzed with 1.0% of lime, basis of fresh matter) x 6 (six times of storage: 0, 24, 48, 72, 96 and 120 hours), with three replicate s. The sugar cane stored without lime showed lower dry mat- ter (DM), crude protein, neutral detergent fiber an d acid detergent fiber contents compared to hydroly zed sugar cane. However, the hydrolyzed sugar cane showed hig her contents of organic matter (OM) and total diges tible nutrients. We reported higher in vitro digestibility of DM and OM when the sugar cane was not hydrolyzed. This can be explaining by better chemical compositi on of sugar cane without lime. The storage of sugar cane without lime shows results more interesting because the chemical composition and digestibility is bett er than hydrolyzed sugar cane. So, we not recommended using lime on the sugar cane. Moreover, the sugar cane w ith- out lime can be stored until 96 hours after cut.

The main goal aim of this work was study the parameters that influence in the spatial variation of the chlorophyll "a" in the surface water of the Orós reservoir, Ceará state, Brazil. It was studied the compari- son of the water in that reservoir, too. Twelve water samples were taken in seven different sites in the reservoir. They were sampled every two months from April/2008 to April/2010. Total phosphorus, water temperature, water transparency and the chlorophyll "a" production were analyzed. To assessment the eutrophication be- tween the sampled sites it was used the Hierarchical Cluster Analysis. Results showed that the eutrophicationallowed observes that the water temperature, water transparence and total phosphorus are influential in the chlorophyll "a" production. The increasing of the water temperature increase the chlorophyll "a" concentration. Hierarchical Cluster Analysis showed that the sampled sites 1 and 2 are similar in relation to water eutrophication and it separates the water in two different groups. The group 1 was formed because of the both high sedi- ment concentration and the low levels of chlorophyll “a” and the group 2 was formed because of the both highwater temperature values and high chlorophyll "a" concentration.

Ni was the last nutrient characterized like essenti al for plants. Its essentiality is due to participa - tion as constituent of urease enzyme, which makes i t extremely important for the metabolism of N. Thus , the objective of this study was to investigate the grow th, content and accumulation of urea and nutrients in cowpea bean plants ( Vigna unguiculata (L.) Walp.) ‘IPA 206’ according to nickel rate and two soil types. The experi- ment was carried out in a greenhouse at Universidad e Estadual do Norte Fluminense Darcy Ribeiro, using a 5 x 2 factorial scheme in a randomized block design wit h four replications. Treatments consisted of foliar applica- tions of five nickel concentrations (0, 20, 40, 60 and 100 mg L -1 Ni) in the form of NiCl 2 .6H 2 O and two soils, a Typic Quartzipsamment and a Tb dystrophic Red-Yello w Ultisol. Ni rates promoted Ni toxicity symptoms j ust on young leaves of bean. These symptoms were charac terized by small reddish spots that have not progre ssed during the time and did not influence on the plants development. The foliar application of Ni increase d levels of this micronutrient in stems, mature leaves, youn g leaves and pods of cowpea bean, indicating high m obility of this micronutrient in the plant, but did not alt er the urea contents, indicating no effect on the a ctivity of urease enzyme. The dry mass of the shoots and the c ontent of others nutrients were not affected by fol iar appli- cation of Ni. Plants grown in Ultisol showed higher growth and higher content of urea and Cu in mature leaves; K and B in mature leaves, young leaves and twigs an d Zn in mature leaves and stem.

The soil management system can modify the natural d istribution of the soil attributes and, con- sequently, the variability of the soil aggregation and organic matter content. Thus, the aim of this w ork was to evaluate the aggregate stability and organic matter content spatial distribution on a Haplic Cambisol under sugar cane cultivation in the Southern Amazonas Sta te, Brazil. A 70 x 70 m square mesh, with regular 1 0 me- ters intervals, was designed over the cultivation a rea, resulting in 64 sample points. Soil blocks wit h preserved structure were collected at 0.0-0.2 m depth in orde r to analyze the aggregate stability and organic ma tter con- tent. The data were submitted to the descriptive an d geostatistical analysis. The soil attributes pres ented a spa- tial dependence structure and the greater range was observed for the mean weighted diameter and aggreg ate class <1.00 mm. Also, there is a spatial relation a mong the mean geometric diameter, mean weighted dia meter and aggregate classes (> 2.00 and 2.00-1.00 mm).

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.

The Caatinga is a vegetation that occurs exclusively in Brazil, typically in the Northeastern region and studies on the floristic composition and phytosociological are prerequisites for understanding the behavior, distribution and structure of the vegetation. Therefore, this study aimed to conduct a phytosociological survey of an area approximately 191 hectares of Caatinga, located within of the Unity Conservation area Grota do Angico Natural Monument, Sergipe state, Brazil. To conduct this study, we used the method of fixed area and the process of systematic sampling, where all individuals included in the 30 plots that showed CAP (circumference at breast height) greater than 6 cm were measured. In total of the survey, we identified 24 species in 20 genres and 12 families. The families with the higher number of species were Fabaceae, Euphorbiaceae e Anacardicaceae. Poincianella pyramidalis (Tul.) L. P. Queiroz, Jatropha mollissima (Pohl.) Baill., Bauhinia cheilantha, Anadenanthera colubrina (Vell.) Brenan. and Mimosa tenuiflora were the most representative species for the phytosociological indices (density, cover, frequency and important value index). The basal area at the study site was 6,95 m2 ha-1 and the volume 28,42 m3 ha-1.