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ADUBAÇÃO FOSFATADA EM CANA PLANTA E SOCA EM ARGISSOLOS DO NORDESTE DE DIFERENTES TEXTURAS
2014
DANIELA BATISTA DA COSTA | PATRÍCIA KARLA BATISTA DE ANDRADE | SILAS ALVES MONTEIRO DA SILVA | DJALMA EUZÉBIO SIMÕES NETO | FERNANDO JOSÉ FREIRE | EMÍDIO CANTÍDIO ALMEIDA DE OLIVEIRA
The present work studied the productivity of plant and ratoon cane in soils with different physical, chemical and mineralogical particulars submitted to phosphate fertilization. Randomized block field experi- ments were located at Japungu Distillery (Paraíba State), at Sugar Cane Experimental Station of Carpina (Pernambuco State) and at Bom Jesus Sugar Cane plant (Pernambuco State), from where Argisoils of sandy, mid and clayey textures were selected respectively. The doses of 0, 40, 80, 120, 160 and 200 kg ha - 1 P 2 O 5 were applied at the bottom of the furrow (fertilization foundation). In the subsequent ratoon cane were applied 0 and 40 kg ha - 1 P 2 O 5 (topdressing) for each of the doses applied at the planting. It was concluded in this study that the productivity of sugarcane plant was positively influenced by phosphorus fertilization planting. The ratoon cane only responded nicely to phosphorus coverage in the less weathered medium texture Argisoils; Phospho- rus fertilization of ratoon sugarcane coverage in clay and weathered Argissolos did not promote increased productivity, restricting its recommendation in Argissolos with these characteristics.
Show more [+] Less [-]CRESCIMENTO, CONSUMO E EFICIÊNCIA DO USO DA ÁGUA PELA MAMONEIRA SOB ESTRESSE SALINO E NITROGÊNIO
2014
REGINALDO GOMES NOBRE | GEOVANI SOARES DE LIMA | HANS RAJ GHEYI | LAURIANE ALMEIDA DOS ANJOS SOARES | ALEXSANDRO OLIVEIRA DA SILVA
Considering the potential of castor beans as an alternative for the production of renewable en- ergy and the lack of information regarding management techniques for its cultivation, this study was conducted to evaluate the effect of different levels of irrigation water salinity (ECw) associated with nitrogen fertilization rates (DN) on growth, water consumption and efficiency of water use by castor bean cv. BRS Energia. The experiment was conducted in lysimeters under field conditions, atCCTA/UFCG, adopting a randomized block designin 5x5factorial scheme with three replications. Treatments consisted of five levels of ECw (0.4, 1.4, 2.4, 3.4 and 4.4 dS m-1) associated with five doses of nitrogen (50, 75, 100;125 and 150 mg kg-1). The increase in water salinity from 0.4 dS m-1 caused linear decrease in the absolute growth rate(TCAap), total leaf area(AF)at 35 days after sowing (DAS), the water consumption and water use efficiency (EUA) for castor bean cv. BRS Energia. Increasing levels of water salinity promoted increase in relative growth rate (TCRap). Nitrogen rate of 114 mg kg-1 increased TCRap and 150 mg kg-1of N promoted greater EUA. Increasing levels of nitrogen at- tenuated at 120 DAS, the effect of electrical conductivity up to salinity level of 2.4 dS m-1 on the leaf area pro- moting higher specific leaf area. There was a significant interaction between ECw and nitrogen levels on elec- trical conductivity and pH of drainage water. Keywords: Ricinus communis L. Quality of water. Mineral nutrition.
Show more [+] Less [-]IMPACT OF GLYPHOSATE ON MICROBIAL ATTRIBUTES OF SOI L PLANTED WITH TWO SPECIES OF PASSION FRUIT
2014
ERIKA VALENTE DE MEDEIROS | KRYSTAL DE ALCANTARA NOTARO | CIDNEY BARBOSA BEZERRA | ANTÔNIO RICARDO SANTOS DE ANDRADE | GUSTAVO PEREIRA DUDA
Glyphosate is one of best known agrochemicals and i s used to prevent the spread of weeds. However, little is known about the impact of this c hemical on non-target organisms such as the soil mi crobial community. Therefore, the objective of this study w as to evaluate the effect of glyphosate on the micr oorgan- ism population and the microbial attributes of soil s cultivated with yellow and sweet passion fruits. The experi- mental design used was complete randomized blocks i n a 3 x 2 factorial scheme with the times of soil s ample collection (0, 5 and 47 days after herbicide applic ation- DAH) and the two species of passion fruit ye llow ( Passiflorae dulis f. flavicarpa O. Deg.) and sweet ( Passiflora alata Dryand) as the factors,with three replica- tions. No impact of the glyphosate herbicide was fo undon the bacterial communities of soil. However, a mild and transitory impact was observedon the fungal pop ulations, encouraging these populationsat 47 DHA. G ly- phosate changed the carbon microbial biomass and so il microbial attributes, except for total organic c arbon. Multivariate, principal component analysis revealed that the total bacteria, endospore-forming bacteri a, total fungi, carbon microbial biomass and metabolic quoti ent attributes of soil are the most sensitive facto rs for pre- dicting the impact of glyphosate on biological indi cators of soil planted with two species of passion fruit yellow ( P. edulis f. Flavicarpa ) and sweet ( P. alata ).
Show more [+] Less [-]SENSIBILIDADE À SALINIDADE DE HÍBRIDOS TRIFOLIADOS E OUTROS PORTA-ENXERTOS DE CITROS
2014
MARCOS ERIC BARBOSA BRITO | PEDRO DANTAS FERNANDES | HANS RAJ GHEYI | ALBERTO SOARES DE MELO | WALTER DOS SANTOS SOARES FILHO | ROBI TABOLKA DOS SANTOS
In order to evaluate the sensitivity of citrus g enotypes: ‘Santa Cruz Rangpur’ lime, ‘Sunki Tropical’ mandarin, ‘Troyer’ citrange, ‘Volkamer’ l emon, and HTR-051 and HTR-069 trifoliate hybrids to salinity during the rootstock formation period in g reenhouse. The genotypes were subjected to five lev els of irrigation water salinity: control, tap water with electrical conductivity (EC w ) of 0.41 dS m -1 and water with EC w of 1.0, 2.0, 3.0 and 4.0 dS m -1 , made from salts NaCl, CaCl 2 .2H 2 O e MgCl 2 .6H 2 O, using the 7:2:1 propor- tion, respectively. The ‘genotypes’ and ‘salinity’ factors were arranged in factorial design (6x5), us ing a ran- domized block, with five blocks and four plants per parcel. The growth and physiological variables wer e evalu- ated registering the most significant effects to sa linity on total dry matter at all genotypes, highli ghting total dry matter accumulation in 'Volkamer' lemon and the hig hest decrease from increasing salinity it is observ ed in 'Troyer' citrange. The 'Volkamer' lemon and HTR – 0 69 can be recommended to formation of seedlings of cit- rus rootstocks under salinity due to its less sensi tivity in the formation of biomass.
Show more [+] Less [-]PARTIÇÃO DE BIOMASSA E ABSORÇÃO DE NUTRIENTES PELO FEIJOEIRO COMUM
2014
RODINEI FACCO PEGORARO | DARIO OLIVEIRA | CRISTIANO GONÇALVES MOREIRA | MARCOS KOITI KONDO | ARLEY FIGUEIREDO PORTUGAL
Studies related to the absorptions and nutrient partitioning in organs of irrigated beans are scarce and very important for the improvement of different fertilization models. This study aimed to evaluate the growth of irrigated common bean in winter, through biomass production and nutrients uptake to organs and shoots. We used a randomized block design with three replications and seven composed of time periods of plant collection (10, 20, 30, 40, 50, 60 and 70 days after plant emergence) with separation in leaves, stem, flower+pod and grains. After determination of dry matter, the content of N, P, K, Ca, Mg and S absorbed by shoots and components of bean was estimated. Nonlinear sigmoid and gaussian models were fitted to characterize biomassa production and nutrient uptake during bean growth. The absorption of by bean decreasing in the following order, in kg ha-1: 138 K, 112 N, 66 Ca, 16 P, 11 S and 7 Mg, indicating the high absorption of K and N and demand of K replacement by top dressing. During the initial growth stage, leaves were responsible for 80% of macronutrients accumulation in shoots. In the final growth stage, grains exported 90, 75 and 65% of P, N and Mg absorbed, showing its high export rate.
Show more [+] Less [-]CULTIVO DE FEIJÃO E MILHO EM SUCESSÃO A PLANTAS DE COBERTURA
2014
JOSÉ LUIZ RODRIGUES TORRES | MATHEUS DE ANDRADE CUNHA | MARCOS GERVASIO PEREIRA | DINAMAR MARCIA DA SILVA VIEIRA
Growing cover crops preceding planting common beans and corn may influence the yield of these cash crops. This study aimed to evaluate the biomass production and decomposition of crop residue cover and yield of maize and beans grown on these soils as coverings of plants. The experiment was conducted under field conditions in the 2011/12 harvest in Uberaba. With a randomized block designed in a split - plot scheme, seven cover crops were used : sunn hemp ( Crotalaria spectabilis ), jack bean ( Canavalia ensiformis DC.), mil- let ADR300, ADR500 and ENA2 ( Pennisetum glaucum L.), Sorgo (S orghum bicolor L.) and brachiária ( Urochloa brizantha cv Marandú), and subplots in annual succession crops (maize and bean). The millets ADR300, ADR500 and ENA2 among Poaceae and jack beans between Fabaceae produced more dry biomass (9.8, 8.9, 8.6 and 3.8 t ha - 1 ), respectively; after 150 days of decomposition of plant residues of sunn hemp, jack bean, sorghum, brachiaria, millet ADR500, millet ENA2 and millet ADR300 were in the order of 67.9; 71.7; 53.8; 61.7; 49.9; 45.5 and 46.7%, respectively; the maize yield was higher when the culture was grown on resi- dues of millet ENA2 (7.2 t ha - 1 ) and jack bean (6.8 t ha - 1 ), while the bean was higher when grown on millet ADR300 (1.3 t ha - 1 ) and sunn hemp (1.2 t ha - 1 ).
Show more [+] Less [-]MEDICINAL PLANTS FROM BRAZILIAN CAATINGA: ANTIBIOFILM AND ANTIBACTERIAL ACTIVITIES AGAINST Pseudomonas aeruginosa
2014
DANIELLE SILVA TRENTIN | KARINE RIGON ZIMMER | MÁRCIA VANUSA SILVA | RAQUEL BRANDT GIORDANI | ALEXANDRE JOSÉ MACEDO
The Caatinga biome covers a vast area in northeastern Brazil and presents a high level of biodiversity. It is known that about 400 plant species are used by semi-arid local communities for medical purposes. Based on ethnopharmacological reports, this study aims to screen 24 species from Caatinga regarding the ability to prevent biofilm formation and to inhibit the growth of Pseudomonas aeruginosa - a major opportunistic human pathogen and an important causative agent of morbidity and mortality. The effects of aqueous extracts, at 0.4 and 4.0 mg mL-1, on biofilm formation and on growth of P. aeruginosa ATCC 27853 were studied using the crystal violet assay and the OD600 absorbance, respectively. The most active extracts were analyzed by thinlayer chromatography and high performance liquid chromatography. Our investigation pointed extracts of four species with potential application for the control of P. aeruginosa: Anadenanthera colubrina (Vell.) Brenan, Commiphora leptophloeos (Mart.) J.B. Gillett, Myracrodruoun urundeuva Allemão, whose antibiofilm effects (89%, 56% and 79% inhibition of biofilm, respectively) were associated with complete inhibition of bacterial growth, and Pityrocarpa moniliformis (Benth.) Luckow & R.W. Jobson, which were able avoid 68% of biofilm formation and inhibited 30% bacterial growth. The qualitative phytochemical analyses reveal the complexity of the samples as well as the presence of compounds with high molecular weight.
Show more [+] Less [-]GREEN EAR AND GRAIN YIELD OF MAIZE GROWN AT SOWING DENSITIES
2014
PAULO SÉRGIO LIMA E SILVA | PAULO IGOR BARBOSA E SILVA | ENIELSON BEZERRA SOARES | EDICLEIDE MACEDO DA SILVA | LUIZ EDUARDO BARRETO DOS SANTOS
One of the characteristics of maize cultivation in the Northeast region of Brazil is the diversity of production systems. One can find from large companies, which adopt modern cultivars and relatively high sowing densities, to small properties, with traditional cultivars grown at low sowing densities (cultivation in pits spaced more than 1.0 m). The objective with this work was to evaluate the effects of sowing density (30, 40, 50, 60, or 70 thousand plants ha-1) on green ear yield and grain yield of maize cultivars (AG 405 and BR 106). Green ears and grain are assessed and marketed differently. Consequently the optimum densities for ob- taining each product may be different. In addition, maize cultivars may respond differently to increased density. Densities were achieved by maintaining a constant spacing between rows (1.0 m) and varying the spacing be- tween pits within the same row. Cultivars and sowing densities were combined in a factorial scheme, arranged in a random block design with five replications. The maximum yield of marketable husked green ears of culti- vars AG BR 405 and 106 were obtained with densities of 59 and 62 thousand plants ha-1, respectively. The maximum grain yield of cultivars AG 405 and BR 106 were obtained with densities of 61 and 70 thousand plants ha-1, respectively. In general, to produce marketable green ears, cultivar BR 106 was better in terms of number of ears, but the other cultivar was better in terms of ear weight. Cultivar AG 405 responds better to increased density for grain production.
Show more [+] Less [-]NÍVEIS CRÍTICOS DE BORO PARA A CULTURA DO GIRASSOL EM SOLOS COM TEXTURAS CONTRASTANTES
2014
MANOEL EUBA NETO | VÂNIA DA SILVA FRAGA | WALTER ESFRAIN PEREIRA | BRUNO DE OLIVEIRA DIAS | JACOB SILVA SOUTO
Boron deficiency in sunflower cultivation can cause decreased production, mainly by the fall of the inflorescence diameter. Most soils, especially in the tropics present low content of boron (B) available. To ascertain the response of sunflower to boron application in different orders of tropical soils with different tex- tures, we carried out an experiment under controlled condition. Were applied to the soil samples collected in the layer 0-20 cm, four doses of B as boric acid (H3BO3) in solutions at concentrations of 0.0; 0.04; 0.08 and 0.16 mol m-3. The soils were: PAC - Argissolo Acinzentado; PVe - Argissolo Vermelho eutrófico; PVA - Argissolo Vermelho-Amarelo; RL - Neossolo Litólico; RY - Neossolo Flúvico; VX - Vertissolo Háplico. The experimental design used was a randomized blocks in factorial scheme 4 x 6 (doses x soils) with four replica- tions and one plant per pot. Quantification of B content was performed by extraction method with barium chlo- ride solution of 5.0 mol m-3 subjected to heating with microwave radiation and determining the B content in the soil was performed by colorimetric technique using the azomethine-H reagent. The contents at levels sufficient to allow the soil B established independent of the dose added, a yield exceeding 90% yield on. The highest dry matter yield of sunflower was associated with the B concentration in the soil between 0.04 and 0.08 mol m-3 and there was a decrease with higher concentrations.
Show more [+] Less [-]RESPOSTA FUNCIONAL DA JOANINHA CRYPTOLAEMUS PREDANDO COCHONILHA BRANCA EM DIFERENTES TEMPERATURAS E SUBSTRATOS VEGETAIS
2014
SERGIO ANTONIO DE BORTOLI | ADRIANA ROSSINI GRAVENA | ALESSANDRA MARIELI VACARI | VALÉRIA LUCAS DE LAURENTIS | CAROLINE PLACIDI DE BORTOLI
This work was carried out to evaluate the functional response of Cryptolaemus montrouzieri Mulsant, 1850 (Coleoptera: Coccinellidae) fed with Planococcus citri Risso, 1813 (Hemiptera: Pseudococcidae) reared on a pumpkin hybrid (Cucurbita maxima x Cucurbita moscata) (Cucurbitaceae), seedlings of Rangpur lime (Citrus limonia) Rutaceae) and potato (Solanum tuberosum) (Solanaceae) at two temperatures. The predation rate of C. montrouzieri was measured using Petri dishes of 15 cm diameter with 1, 2, 4, 8, 16 and 24 adults of P. Citri. One third instar larva, one fourfh instar and one newly emerged adult (without differentiation of sex) of C. montrouzieri were added to each plate. The study was conducted in climatic chambers at temperatures of 25 and 30 º C and photophase of 12 hours. The predation rate was evaluated after 24 hours of prey exposition to the predator, by counting the number of preys trapped in the different treatments and control. The statistical design was completely randomized with four treatments x 6 subplots with 7 repetitions, the two temperatures. The values obtained were subjected to analysis of variance, to relate the number of scales preyed by larvae and adults of C. montrouzieri set up in different substrates. The amount of prey consumed by larvae and adults of the predator increased with increasing the prey density until it reaches a plateau, characterizing functional response type II. In general, the number of scales preyed by larvae and adults of C. montrouzieri was higher on potato and under temperature of 30 °C.
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