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.

The aim of this study was to evaluate the production of Freshwater Angelfish (Pterophyllum scalare) in different stocking densities in cages polycultured with Amazon River Prawn (Macrobrachium amazonicum). Four treatments were evaluated (1; 2; 3 and 4 fish.10 L-1) using two ponds and 24 experimental units. Water quality parameter reached adequate levels for the species. Production data were submitted to ANOVA. Fish produced in the lowest density showed higher values of final weight and standard length, and lower total biomass in comparison with the others treatments. Feed conversion rate, survival, batch uniformity and body factor were not significant different among treatments. The highest density tested produced more fish and gross yield than the others treatments. The density 20 fish.10L-1 is recommended to produce Freshwater Angelfish in cages polycultured with Amazon River Prawn.

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.

The objective of this study was to compare the weather data obtained from both conventional (CWS) and automatic (AWS) weather stations, in Jaboticabal, SP, Brazil (latitude: 21º14'05" S, longitude: 48º17'09" W and altitude: 613,68m), from July 1997 to June 2002. Daily data were collected and analyzed statistically by regression analysis. The results showed a good relationship between CWS and AWS, specially for air mean temperature, minimum temperature, maximum temperature and rainfall. Air humidity and atmospheric pressure showed the highest errors, respectively equal to 5,69% and 3,64 hPa. Wind velocity at 2m did not show good precision and accuracy because its estimation for CWS.

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 present work objectified to detect tendencies of long period in the annual averages of the air temperature. We analyzed minimum, mean, and maximum temperature, absolute minimum, and absolute maximum. Twenty-four meteorological stations on the Northern Northeast (Ceará, Rio Grande do Norte, Paraíba and Pernambuco) were used. We used the historical series from 1961 to 1990. To identify the tendencies, we used the analysis of lineal regression analysis. The Student's t-test was used to verify the statistical of the coefficients of lineal regression. We observed an increase of the minimum, mean, maximum temperature, and absolute minimum. The absolute maximum temperature didn't present significant tendencies of increase nor of decrease. We conclude that has had a decrease of the annual thermal amplitude of the temperature on the Northern Northeast, mainly, due to the increase of the night temperature.

The knowledge about the magnitude of the genetic variability of collection is great importance to the success and longevity of plant breeding programs. Same authors affirm to exist genetic variability in elephant grass (Pennisetum purpureum), being expanded with the use of millet (P. glaucum) in the hybridization. This work presents considerations on genetic variability in elephant grass germplasm and the main methodologies used to assess this variability. Based on the works studied, the methodologies (principal component, canonical variables and agglomerative methods, based in the euclidian and Mahalanobis distances; Jaccard' index and cluster' methods, based in the Ney & Li distances) were efficient in to determine the genetic variability in most genotypes studies in Brazil and other countries, both biometric and molecular level, way be exploited by breeding programs through methods of selection intra and interspecific hybridizations.

Excessive salt can to promote water soil retention, reducing your availability to plants. Besides, they can interfere in protoplasm metabolism. The plants ability to survive in salinity conditions is an important factor to geographic distribution and agriculture in salinized regions. The objective of this work was to verify the effects of the NaCl in the growth, dry matter distribution and N, K, Ca, Mg, Na, and Cl content in young plants. The experiment was conducted in 'Leonard' pots, with nutrient solutions, with NaCl (0, 25, 50 and 100 mmol L-1). Increasing of NaCl concentration reduces growth and total dry matter. There was an increase of N and K content, in shoots, and N and Mg content in roots. There was an reduction in Mg content in shoots, and reduction of Ca content in roots with increasing of NaCl. Leucaena plants were inefficient to exclude Na and Cl, in shoots principally.

In order to evaluate the effects of chemicals amendments sulphuric acid and gypsum to decrease sodicity in a saline-sodic soil of Irrigated Perimeter of Condado, Paraiba State, Brazil, an experiment was carried out in a green house of the Departamento de Solos e Engenharia Rural, Centro de Ciencias Agrarias, Universidade Federal da Paraiba, Areia, Paraiba State, Brazil. The experiment was conducted in 2x5 factorial design referring to chemical amendments sulphuric acid and gypsum at levels equivalent to 0; 1.8; 3.6; 5.4 and 7.2 g kg-1 of sulphate (SO4 -2). The chemical amendments exercised positive effects on reduction of exchangeable sodium percentage and pH in saturation extract evidencing improvement in relation to sodicit and alkalinity of the soil. The gypsum was superior to sulphuric acid in reduction of exchangeable sodium percentage and soluble sodium content in the soil solution.

To evaluate the effect of the temporary replacement of shrimp ration (RC) by chicken ration (RF) in the culture of Litopenaeus vannamei shrimp, juvenils (1.07 ± 0.26 g), were cultivated (52/m2) for 30 days in 50 L boxes, with constant aeration, 0% of water exchange and fed with 10% of its biomass/day at 08:00 and 16:00 h, according to the treatments: (1) RC; (2) 1 week RC + 1 week RF, alternate; (3) RF and (4) 1 day RF + 1 day RC, alternate; with 5 repetitions each. There was no difference (P <0.05) in the weight of shrimp on the basis of treatments applied at the beginning (Kruskal-Wallis, P = 0003), 15 days (Kruskal-Wallis, P = 0.98) and at 30 days (Kruskal-Wallis, P = 0.07) to experiment. The Specific Growth Rate (rm ANOVA, P = 0.28) and survival (Friedman, P = 0,34 the animals were significantly similar, indicating that these parameters were not affected by treatments, with the possible replacement of shrimp ration by chicken ration, as a measure of containment of expenditure, for short intervals of time. Studies are needed to validate these results in earth ponds.