In order to study the effect of nitrogen sources upon the yields and nutrition of corn for silage and on the chemical attributes of a Cambisol, at Northern of Minas Gerais, Brazil, under calcareous water. The cultivar used was Decalb 390®, with a spacing of 0,8 m x 0,2 m. The base fertilization consisted in 330 kg ha-1 of formulation 4-30-10 and 50 kg ha-1 of FTE-BR12. Two equal dosages of 40 kg ha-1 of K2O, in the KCl form, were applied 45 and 60 days after corn sowing (DAS), phenologic phases V7 and V10 . The experiment it was realized in a randomized blocks design with six repetitions, been the treatments constituted by: ammonium sulfate (topdressing manuring), urea (topdressing manuring), Crotalaria juncea (before de maize crop). The Nfertilizers were applied parceled into three equal dosages of 40 kg ha-1, 30 DAS, with 15 days between fertilizations. The corn yields increased above control treatment average in 33, 27 and 14 t ha-1 with ammonium sulfate and urea topdressing and with C. juncea pre cropped, respectively. The ammonium sulfate use allows better recovery rate of the N applied by the extractor and higher uptake of Fe, Mn, Zn and S by the corn plants.

The aim of this study was to evaluate the performance of varieties of common bean in notillage on biomass of fallow vegetation as a function of crop fertilization. The study was conducted at Bujari, AC. The experimental design was a randomized complete block split plot with four replications. The experiment consisted in the cultivation of three varieties of common bean in no-tillage on weed straw, with and without fertilization at planting subplot. The variables analyzed were grain yield, final stand, number of pods per plant, number of grains per pod and weight of hundred grains. The data were submitted to the F test and means were compared by Tukey test (p<0,05). The bean variety Carioca Pitoco has better grain yield than the Carioca and Rosinha varieties on the first year of no-tillage system. The crop fertilization increases the yield of varieties of beans grown on straw till the fallow vegetation.

The P critical levels in plants depend from soil characteristics which reflect phosphate buffer power. In Pernambuco, soils mineralogical characteristics change at different regions where corn is cultivated. To evaluate P critical levels in corn plants in soil cultivated in different soils and contact periods of this element in the soil, aiming to study the relationships between these critical levels and P adsorption, it was realized an experiment using subsuperficial samples of a Vertissolo Ebânico órtico (VEo) (Mollisol), clay textured with predominance of 2:1 clay mineral and a Nitossolo Vermelho distroférrico (NVdf) (Nitosol), high clay content, predominantly hematitic, colleted at the semi - arid and humid regions of Pernambuco State, Brazil, respectively. The P doses were defined in function of the levels 0; 0.2; 0.4; 0.8 and 1.0 from the P Maximum Capacity of Adsorption (CMAP) of each soil and were incubated by 90; 60; 30; 15; and 0.5 days. The experiment was real- ized into a greenhouse in a factorial scheme (5x5x2), five P levels, five incubation periods and two soils, in randomized blocks delineation with three replicates each. Corn plants were more efficient to utilize P in NVdf, the soil with higher CMAP. The corn shoot critical levels decreased in accordance to the period of incubation in VEo, the soil with lower CMAP.

The objective was to evaluate the effect of the omission of macronutrient and micronutrient boron in dry matter production, the characterization of the symptoms of nutritional deficiencies and mineral composition in plants of ipeca, an experiment was conducted in greenhouse conditions by the technique the missing element and visual diagnosis. A randomized block experimental design with four repetitions and the treatments were: complete and omissions of N, P, K, Ca, Mg, S and B. The analytical results demonstrated that the production of dry matter was affected in all of the treatments with omission of nutrients and that the ipeca plants presented characteristic symptoms of nutritional deficiencies due to the omissions of N, P, K, Ca, Mg, S and B and the concentrations of the macronutrients and of the micronutrient boron in the different parts of the ipeca plant varied when a certain nutrient was omitted in the solution.

Considering that milk is susceptible to fraud, this study aimed to evaluate the effect of different concentrations of sodium citrate and fortifier in density and freezing point of milk. The addition of citrate in 0.1%, the maximum regulated by Brazilian legislation, was sufficient to decrease the average freezing point for 0.021 °H and increase the density average in 0.0008 g cm - 3 . In these samples was possible to add up to 5.6% water without exceeding the Brazilian standards density and freezing point. The fortifier added to milk in con- centrations higher than 0.05% decreased the average freezing point 0.0024°H compared to the control treat- ment. The average density difference only in the group with addition of 0.44% of tonic, an increase of 0.0034 g cm - 3 compared to the control treatment. However, the dilution recommended by the manufacturer (0.007%) not changed density and freezing point average of milk. The results showed that the addition of citrate in percent- ages permitted by Brazilians law was able to change the freezing point and the density of milk. It should be pointed that in direct UHT process the evaporation of water excess from milk with 0.1% of citrate is based on - 0.530 o H, it is possible that the removal of the incorporated water in UHT process could be incomplete, and can be present in percentages higher than 5%. Thus, the manufacturer recommended concentration of fortifier did not change the density and the freezing point of milk.

The objective of this study was to evaluate the g rowth of cowpea under the effect of herbicides fomesafen and bentazon + imazamox. The experiment w as conducted in a randomized block design, using th e split-plot scheme. In the plots were evaluated thre e weeds management systems (culture kept weeded by hoe- ing, with application of fomesafen (250 g ha -1 and the mixture of herbicides bentazon + imazamox (1.200 + 56 g ha -1 )) and in the subplots, 10 evaluation periods: 05, 12, 19, 26, 33, 40, 47, 54, 61 and 68 days after em er- gence (DAE). In each evaluation were collected rand omly in two of the four rows of the floor area of t he plots, three plants of cowpea to determine the following c haracteristics: leaf area, dry mass of leaves, stem , pods and total per plant, leaf area index, leaf area ratio, as well as the rates of absolute and relative growt h and of net assimilation. At harvest, we evaluated the number o f plants (stand), number of pods per plant, number of seeds per pod, 100-grain weight and grain yield. The fome safen caused severe intoxication in cowpea, delayin g flow- ering and harvest in seven days, while reducing pro ductivity. The mixture of the herbicides bentazon + ima- zamox did not affect the characteristics related to the growth of cowpea plants as well as the product ion compo- nents.

The morphogenesis determines the model of plant growth, and is, among other factors, under the influence of nutrient availability. In this context, the aim of this work was to evaluate the effect of using wastewater from the dairy industry (RLL) as a supplier of nutrients in the morphogenesis of grass Mombaça. For this we studied six doses of liquid dairy waste, corresponding to: 10, 50, 100, 150, 200 and 400 m³ ha-1 evaluated in four production cycles and compared to chemical fertilizer. The treatments were arranged in a completely randomized design with four replications compounds. We measured the characteristics of expansion and leaf appearance, leaf senescence, stem elongation and tillering. The application of wastewater from the dairy industry has positively influenced the leaf elongation rate, leaf appearance rate, stem elongation rate and the rate of tillering. A reduction in the rate leaf senescence and the phyllochron in the grass. The application of 400 m³ ha-¹ RLL guarantees satisfactory morphogenic indices in intensive grazing system, replacing up to 25% of phosphorus and potassium fertilization of 100%, having also a positive residual effect on the growth of grass. The liquid waste is a potential supplier of dairy grazing potassium for the pastures.

The Ceara State has a variety of species of non-traditional fruits that are consumed in natura and/or processed by local population, with economic potential for agro-industrial processing, however, still poorly studied. In this context, the aim of this research was to evaluate the genetic variability of puçazeiro ‘Coroa de Frade’, native tree from coastal vegetation of Beberibe, Ceará, Brazil, by physico-chemical and chemical characteristics of their fruits. Fifteen genotypes were evaluated. The traits analyzed were: soluble solids (SS), titrable acidity (TA) (% of citric acid), pH, SS/TA ratio, total sugars, reducing sugars, starch and, total and soluble pectin. The genotypes were characterized as a good alternative to the market of exotic fruits, showing high values of SS (20,40 a 31,00 °Brix) and low mean values of titrable acidity (0,27 a 0,58 % of citric acid), producing SS/TA ratio ranged between 37,5 and 102,43, with emphasis on the genotype '8', which pre- sented SS/TA ratio of 95.05. The genotypes showed fruit netting with high starch (> 1%). The values of total pectin (0.35 to 0.98%) and soluble pectin (0.13 to 0.74%) reinforcing the use of this fruits in the industry, with low cost to manufacture of candy and jellies. The repeatability analysis showed that most of the observed varia- tion among genotypes is associated with the genetic component. Therefore, it can be concluded that the studied genotypes of puçazeiro 'Coroa de Frade' showed wide genetic variability and have fruits indicated even for fresh consumption as well as for processing.

This study was carried out during April to August of year 2009, in field conditions at the horti- culture department Centro de Ciências Agrárias – Universidade Federal da Paraíba, in Areia – PB, aiming to evaluate the effect of nitrogen rates in the presence and absence of bovine manure in the sweet potato yield. The experimental design used was randomized blocks, with four repetitions in factorial scheme 6 x 2, being six nitrogen doses ( 0, 50, 100, 150, 200, 250 kg ha-1 of nitrogen) in the presence and absence of bovine manure. The evaluated variables were commercial roots average weight, commercial roots production plant-1 and com- mercial productivity of roots. The average weight of commercial roots, depending on nitrogen doses in the presence of bovine manure has increased in a linear way in order 0,31 g each kg of nitrogen applied, with maxi- mum weight 233,6 g with 250 kg of nitrogen ha-1. In bovine manure absence it was achieved average weight of 192,1 g. The maximum productivity of commercial roots plant-1 in the presence of bovine manure was 235,42 g, obtained with 243,75 kg ha-1 of nitrogen. In organic fertilizer absence, it was achieved the average of 127,1 g of commercial roots plant-1, depending on nitrogen doses. The dose of 183 kg ha-1 of nitrogen was responsible by maximum productivity of 13,6 t ha-1 of commercial roots, in the presence of bovine manure, while in its absence was achieved medium productivity of 7,9 t ha-1. The cattle manure increased the efficiency of nitrogen production characteristics of sweet potato and set nitrogen use in coverage and cattle manure at planting pro- vides marketable yield of sweet potato than the national average.

The systems of harvesting sugar cane can cause changes in fertility, quantity and quality of organic matter and the degree of oxidation, altering soil carbon stocks. Given this context, the objective was to evaluate the production of dry biomass (DB), soil fertility, the content of total organic carbon (TOC), the car- bon in particle size fractions (particulate organic carbon (COp) and organic carbon associated with minerals (COam)) and oxidizable organic matter fractions (F1, F2, F3, F4 and F1 / F4) in manual harvesting (CMa) and mechanized (CMe) of sugar cane. The sampling for biomass production was conducted in area of 1 m 2 at four points per plot, soil samples were collected at depths of 0.00 - 0.05; 0.05 - 0.10; 0.10 - 0.20 and 0.20 - 0.40 m. The average annual production of dry biomass in the area CMe was 17 times higher when compared to the area of CMa; The pH and phosphorus content was significantly lower in the larger depths area CMa when compared with that of Cme; the harvesting system caused significant CMe in TOC, COp and COam depth 0.00 - 0.05 m increases when compared to the CMa system; There were not significant differences in the oxidizable fractions (F1, F2, F3 and F4) of the organic carbon in the areas of CMa and CMe.