In Brazil, the production of watermelon with seeds is highly representative. However, available information about fruit quality of different varieties grown in the same environment is still rare, which makes it necessary to carry out trials that can fill this gap. Thus, the present study aimed to evaluate the postharvest quality of different varieties of watermelon (Crimson Sweet, Charleston Gray, Sugar Baby, Fairfax and Tendersweet), grown under conventional conditions in Mossoró - RN. The experiment was carried out from September to November 2008 in the experimental field of the Federal Rural University of the Semiarid (UFERSA). The data for the fruit quality were recorded in the Laboratory of Postharvest of UFERSA. The experiment was set under a completely randomized design with six replications and each replication consisted of a fruit. The quality characteristics were analyzed: fruit fresh mass (kg), fruit dimensions (greater length and width), overall appearance, pulp yield in percentage, seed characteristics, pH, acidity, vitamin C, soluble solids and SS/TA ratio. The physical determinations showed variations for fruit fresh mass (4.2 to 9.7 kg), pulp yield (42.0 to 58.5%), rind thickness (1.1 to 2.5 cm), as well as to the number and mass of seeds. In the physical-chemical determinations it was observed phenotypic uniformity among the varieties for almost all variables and, although all of them favorable to consumption, this result indicates narrowing of the genetic basis of varieties, which makes it necessary the evaluation of other genotypes.

This work aimed to evaluate the effect of the use of calcium nitrate on the reduction of stress in the melon plants exposed to excess salt in the irrigation water. The experiment was carried out at the Centro de Ciências e Tecnologia Agroalimentar (CCTA/UFCG), Pombal-PB, from 09/19/2009 to 11/20/2009, using the hybrid melon 'Hales Best Jumbo'. The treatments consisted of the use of two levels of salinity of the irrigation water (0.3 and 5.0 dS m-1) versus rates of N in the form of calcium nitrate (5.5; 6.25; 7.0; 8.5 g N per plant). The experimental design was in randomized blocks, in factorial scheme 2x4, with four repetitions. The highest rates of photosynthesis, stomatic conductivity, transpiration, leaf area, total dry mass and the fruit yield per plant were observed in melon plants irrigated with water of low salinity (0.3 dS m-1) compared to the ones with the saline water (5.0 dS m-1), and for the rates of N between 6.10 and 8.5g of N per plant for both levels of salinity. The suply of N in the form of calcium nitrate was effective on reducing the stress in melon plant the caused by the salinity of the irrigation water up to the rates of 6.20g of N per plant. In absolute terms we can affirm that the best performance of the melon plant was achieved with the dose of 6.25g of N per plant when irrigated with water of low salinity.

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.

This experiment was carried through with objective to evaluate bromatologicament the aerial part and the root of 11 (eleven) to cultivate of cassava, thus determining information for the animal consumption. The experiment was developed in the Experimental Station "Felipe Camarão" pertaining to Empresa de Pesquisa Agropecuária do Rio Grande do Norte S/A - EMPARN, situated in São Gonçalo do Amarante - RN. The following variable had been evaluated: Dry substance, mineral substance, organic substance and rude protein, of the root and aerial part and fiber in acid detergent, fiber in neutral detergent, etéreo extract, insoluble nitrogen in acid detergent, insoluble protein in acid detergent,, total carbohidrates and not-fiber carbohidrates only of the aerial part of the cassava. The used experimental delineation block-type complete was casualizados, with four repetitions. The experimental treatments had been the following ones to cultivate of cassava, proceeding from the Experimental Stations of da EMEPA, EMBRAPA Mandioca e Fruticultura, EMPARN: Cigana Preta, Surrão, Pão da Tarde, Manteiga, Salangó, Osso Duro, Amazonas, Eucalipto, Monge, Bahia Preta e Bravo Preto. It concludes that we must limit the consumption of the aerial part of any to cultivate of the cassava the what concerns amount of indigestível fiber. On the other hand, to cultivate studied them present an excellent Rude Protein concentration. To cultivate Brave if it detaches for presenting one high amount of protein (12.88%).

Macambira is a bromélia used in the alimentation of man and domestic animals on Northeast of Brazilian, especially in times of drought. The study was conducted to evaluate at identifying breaking dormancy methods and verifying how temperature and light can affect germination of its seeds. In the first experiment, the seeds were treated the following treatments: immersion in acetone, in alcohol, to eter, hot water, wash in running water, dry cold and dry heat, aiming at breaking dormancy and control. Were determinate the percentage of germination, first count of germination, index of velocity of germination and the mean time of germination. In the second experiment, after treatment of immersion in acetone during 60 minutes, the seeds were germinated under the following conditions: continued light and 25 ºC constant; continued light and 30 ºC constant; continued light and 35 ºC constant; continued light and temperatures (35 ºC/8 h and 20 ºC/16 h); continued dark and 25 ºC constant; continued dark and 30 ºC constant; continued dark and 35 ºC constant; continued dark and temperatures (35 ºC/8 h and 20 ºC/16 h); alternation of light (dark/16 h and light/8 h) and temperature of 25 ºC constant; alternation of light (dark/16 h and light/8 h) and temperature of 30 ºC onstant; alternation of light (dark/16 h and light/8 h) and temperature of 35 ºC constant; alternation of light and temperature (dark/20 ºC/16 h and light/35 ºC/8 h) and alternation of light and temperature (dark/25 ºC/16 h and light/35 ºC/8 h). It follows that the immersion in acetone during 60 minutes was the treatment more efficient to promote the of vigor and germination of seeds. The seeds do not germinate in the light absence, behaving as fotoblásticas positive.

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.

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.

The Alismataceae (excluded Limnocharitaceae) comprises twelve genera of herbaceous aquatic plants. Only two of its genera (Echinodorus and Sagittaria) are native to the Neotropics. A survey of the species of Alismataceae confirmed the occurrence of four taxa of Sagittaria and eleven of Echinodorus from the semi-arid region of northeastern Brazil. Analytical keys to differentiate the genera and species are provided, as well as illustrations of their taxonomic characteristics and data on their geographical distribution. Echinodorus macrocarpus to be considered synonymous with E. pubescens. Echinodorus reticulatus is considered as a different species from E. longipetalus. There are five excluded taxa from the Brazilian semi-arid region: E. grandiflorus, E. macrophyllus, E. martii, E. bolivianus, and E. decumbens.

The aim of this study was to evaluate silicon (Si) and two phosphorus (P) extraction methods in "Latossolos" under corn and sorghum. The experiments were conducted in green-house, in a completely randomized, with corn for the 5x2x2 factorial arrangement, consisting of five P rates (0, 96, 192, 288 and 480 mg dm-3) in the absence and the presence of 300 mg dm-3 of slag in two "Latossolos" and four replicates, while for sorghum the experimental design was 5x2, and is used only one soil. The experimental plots were subjected to two incubation periods, the first with slag (only half of the plot) and then with lime. In the first experiment two plants were cultivated corn pot for 45 days and then ten plants of sorghum for 60. After the experiments took place the collection of plants being evaluated for plant height, stem diameter and dry weight of maize shoots and just shoot dry matter of sorghum, the levels of Si and P in samples soil and plants. The medium texture soil showed better correlations of Si and P. For the Olsen P method as both the Mehlich 1 had good correlation. Sorghum showed higher correlation coefficients than corn.