The objective of this work was to evaluate to the sowing time of the Brachiaria brizantha forage intercrop with two upland rice cultivars on the agronomics characteristics of both species. It was used randomized blocks in experimental design arranged in factorial scheme 2x2+4, with four replicates. The first factor was constituted by the upland rice cultivars (BRS Primavera e BRSMG Curinga) and the second factor by two sowing times of B. brizantha forage (simultaneous sowing between rice and forage and sowing of the forage in the flowering of the rice). The additional treatments consisted of the sole crops upland rice cultivars and B. brizantha forage for each sowing time. In rice was evaluated the height of the plants, bedding, difficulty of the harvest, the number of panicles per area, grain per panicles, percentage of full and empty grains, 100-grain mass and grain yield. In the B. brizantha forage was evaluated the height of the tillers, the total dry mass and the rate of cultural growth. It was observed that the B. brizantha forage interfered in the productivity components of both upland rice cultivars and difficult significantly the harvest of the rice. The upland rice cultivars showed small competitive capacity with the B. brizantha forage when the establishment of the forage occurred simultaneously to the rice. However, to the measure that the sowing was occurred with the established rice already, the B. brizantha forage had his growth suppressed.

Seed hydration is considered the most important external factor interfering on germination. This study evaluated the tolerance of Gliricidia sepium (Jacq.) Steud seeds to water and salt stresses during germination. Seed germination was observed in four 100-seed replications, in polyethylene glycol (PEG-6000) or sodium chloride (NaCl) solutions with four osmotic potentials levels (0; -0.5; -1.0 and -2.0 MPa), arranged according to a completely random design, simulating water and salt stresses, respectively, using four replications of 100 seeds. The germination percentage and germination velocity index were estimated. Percentage germination of the control seeds averaged 94%, and reduced to 77.6% and 44.3% in -1.0 MPa NaCl and PEG solutions, respectively. No germination was observed in -2.0 MPa. Germination velocity index showed the same trend. Gliricidia sepium seeds showed less tolerance to water than to salt stress, and in this condition they are not tolerate to osmotic stress up to -0,5 MPa.

An experiment was carried out at a greenhouse of Plant Science Department of the Universidade Federal Rural do Semi-Árido (UFERSA), Mossoró-RN, in the period of May to June of 2008, with the evaluate the agronomic performance of rocket in function of their times of decomposition of Ipomoea asarifolia incorporated. A completely randomized desing with six treatments and four replications. The treatments consist of: T1 (45 days incorporated); T2 (30 days incorporated); T3 (15 days incorporated); T4 (0 days incorporated); T5 (336g vaso-1bovine manure); T6 (Control no fertilized soil). The rocket cultivar grown was cv. Cultivada. The evaluated traits were: plant height, number of leaves per pot, dry mass and yield of grains. All the times traits were significantly affected by the amounts of Ipomoea asarifolia incorporated. Height mean value for plant height, dry mass and yield of grains were obtained in the time 11,8 days incorporated of 18,3 days for number of leaves.

The lettuce is a leafy vegetable and when it is cultivated in regions of intense solar radiation it can¿t develop it's full genetic potential. In this direction this work had the objective of evaluating the productivity of the Butterhead lettuce cultivar using different types of screens in the region of the Submédio São Francisco. The experiment was carried out in raised planting beds, using black screens with 30 and 50% of shading, white screens and in the open sun. The statistical design was the factorial 2x4 and the means were compared by the Turkey test at 5% of probability. In each treatment a termohigrometre and temometers at 40 cm from the ground were coupled with a black globe to get the radiant thermal load, the temperature of the air and the humidity index. At the end of the trial chlorophyll, the diameter of the head, plant height, the number of leaves per plant, the leaf area, fresh and dry weight of plants were collected. The screens affected the parameters analyzed and the treatment PS and TB of shading were the best for commercial parameters.

The present work had the aim to study the seasonal variation of the groundwater quality for irrigated at Lagoa de Salsa region in the district of Tibau (RN) during in the rainfall and drought season of 2008 and 2009. Sample water 24 were collected in aquifer distributed spatially in produced area in region at the two stationsalong. The variables electrical conductivity, Na, Ca, Mg, SAR, CO3, HCO3 and Cl were analyzed. The results showed that majority of the groundwater for irrigation in the Tibau microregion have use limitation. The concentrations for rain season was low in relation drought season, decreased salinity risk to mayoral parameters analyzed.

This experiment aimed to objective evaluate the appearance of the fruits and taste of waterde-coconut during the storage. Were harvested fruit cultivar Green Dwarf with six months of age, from the municipality of Rio do Fogo-RN then were transported to the laboratory Agriculture of UFERSA, which were previously assessed on the appearance of the fruits and taste of water. Part of the fruit has been coated with paraffin, and the other part remained untreated. Then, the fruits were stored in cold with temperature of 12±1ºC e 90±2% UR. Where they remained for 28; 35; 42; 49; 56 e 63 days. In each period the fruits were evaluated on their appearance and taste of the water using a hedonic scale of nine points, ranging from extremely liked and disliked. The experimental design was completely randomized, factorial arrangement 2x6, two types of coating fruits (fruits with and without paraffin), six times the storage of fruits (28, 35, 42, 49, 56 e 63 dias) with three replicates of 05 fruits, was used to test Friedman average of a 5% probability. The coating with paraffin kept good appearance of the fruits for a longer period of time in relation to fruit without paraffin. The taste of the water, practically, did not differ with the coating fruits.

The aim of this work was the study of proline and aminoacids accumulation in two cowpea ultivars, previously identified as tolerant (Pitiúba) and sensitive to salinity (TVu 2331), along the stress exposition time. Plants of both cultivars were exposed to NaCl 75 mM (salt stress), added at rate of 25 mM day-1 in nutritious solution and its behavior was compared with control ones, kept at the same environmental conditions. In general, salt stress inhibited more the growth in TVu 2331 cultivar. The stressed plants of this cultivar also presented larger proline accumulation in their leaves, suggesting the existence of a protection mechanism. TVu 2331 cultivar also presented tendency of more accumulation of aminoacids in the leaves and roots, which could have occurred due its higher growth inhibition.

This work aimed to evaluate melon cultivars under salt stress conditions. The work was carried out in green house of the Tecnology and Social Sciences Department (DTCS) of the University of the Stete of Bahia (UNEB), at Juazeiro - BA. The experimental design was totally randomized, with four replications in a factorial squeme 3 X 4 (cultivars and salt solutions) and the averages were compared by Tukey test at 5% probability. Melon seeds of the cultivars AF682, Gaúcho e Sancho were sowed in 15 L vases with previously salinizied soils with the conductivities 0,17; 2,23; 4,95 e 6,10 dS.m-1. The emergence percentage and emergence speed rate (IVE) were evaluated. Once the plants have reached blossoming, the were harvested and the fresh matter weight was obtained. After that the plants were dried at 75oC for 72 hours, for dry matter obtention. Were also messuered shoots length and number of leaves per plant. The relative chlorophyll index was obtained after 13, 20, 26 and 40 days after sowing, in three leaves per plant, with a portable chlorophyllmeter Minolta. The leaves of all plants were fotocopied and identified for leaf area (cm2) evaluation. The salt stress induced by the 6,10 dS.m-1 condictivity brought up the information that AF682 cultivar, is less tolerant to soil salinity than Gaúcho and Sancho cultivars.

The present work had as objective to evaluate the influence of pre-germinatives treatments to overcome dormancy in seeds of albizia (Albizia lebbeck) with different colorations. It took place an experiment at greenhouse UFERSA, in Mossoró-RN, in completely randomized design with the treatments distributed in outline factorial 8x2, with the factors treatments for pre-germination and classes of seeds (clear seeds and dark seeds), in four replications of 25 seeds. The germinative pré-germinative consisted either in the immersion of the seeds in sulfuric acid for ten, 15 and 20 minutes; immersion in sodium hypochlorite for ten, 15 and 20 minutes; cutting in the tegument in the opposite side of the embryonic axis and the control (the control was represented by intact seeds). Were analyzed the following parameters: first germination count, germination speed index, and percentage of germination. . By considering the results, it was observed that the dark seeds were better than clear seed. The immersion treatments in sulfuric acid for 10 and 20 minutes and the cutting in the tegument were the most efficient for the break of seeds dormancy.

The purpose of this work was to verify soil respiration kinetics in two sites in the semi-arid region of Paraíba, Northeast of Brazil. The first was a Mimosa hostilis Benth (jurema preta) colonized site, and the other was a degraded area without vegetation. Soil respiration was estimated every hour during a period of 12 hrs. Absorption of the liberated soil CO2 was obtained using a KOH 0.5 N solution. The amount of absorbed CO2 was determined through titration with a HCl 0.1 N solution. Temperature was measured at the surface and 10 cm deep in the soil in both areas. It was observed that the highest level of microbial activity, at the jurema preta site, occurred from 10:00 to 12:00 o¿clock AM. The lowest level of microbial activity was observed when temperature reached 50 oC. In the degraded area, microbial activity reached a maximum at 14:00 o¿clock PM due to the reduction of soil temperature.