Affiner votre recherche
Résultats 1-10 de 197
FITOSSOCIOLOGIA DE PLANTAS DANINHAS EM CONVIVÊNCIA COM PLANTAS DE COBERTURA Texte intégral
2014
SUZETE FERNANDES LIMA | PAULO CÉSAR TIMOSSI | DIEIMISSON PAULO ALMEIDA | UADSON RAMOS DA SILVA
In agricultural areas of Cerrado, where there is no possibility of making two cultivation to the year, areas before cultivated with soybeans or corn, remain in fallow until the next crop year, where weed inci- dence is high. In this research was aimed assess the potential for weed suppression by cover crops, when sown in the off season of annual crops. The experimental design was a randomized block with eight treatments (Urochloa ruziziensis, Pennisetum glaucum, Crotalaria juncea, Crotalaria spectabilis, Styzolobium aterrimum, Canavalia ensiformes, Cajanus cajanand Stylosanthes macrocephala + Stylosanthes capitata) in four replica- tions. The evaluations were performed at 45, 90, 135 and 180 days after the sowing (DAS), with determination of dry mass, plant density and vegetal cover over the soil afforded by cover crops and weeds. The population dynamics was evaluated by means of phytosociological parameters. It is conclude that the weed community presents variations during the development cycle of the cover crop and the greater biomass production, soil cover vegetal and weed suppression was obtained with the U. ruziziensis.
Afficher plus [+] Moins [-]SCREENING OF FLUORESCENT RHIZOBACTERIA FOR THE BIOCONTROL OF SOILBORNE PLANT PATHOGENIC FUNGI Texte intégral
2014
ANELISE DIAS | RAFAEL SANCHES PACHECO | SILVANA GOMES DOS SANTOS | GUSTAVO RIBEIRO XAVIER | NORMA GOUVÊA RUMJANEK | RAUL DE LUCENA DUARTE RIBEIRO
The biocontrol of soilborne plant pathogens represents a promising approach from the environ- mental and practical points of view. Fluorescent pseudomonad rhizobacteria are well known by their antagonis- tic capacity towards several plant pathogens due to a diversity of antimicrobial metabolites they produce. This study was conceived to select and characterize rhizobacteria having antagonistic potential towards the patho- genic fungi Rhizoctonia solani and Sclerotium rolfsii. A total of 94 bacterial strains isolated from the rhizospheres of four vegetable species under organic cultivation were evaluated. Twenty-two strains which predominate in lettuce and rudbeckia rhizospheres showed identical biochemical profiles to Pseudomonas fluo- rescens, while in kale and parsley rhizospheres identical profiles to Pseudomonas putida (subgroups A and B) strains prevailed. Two types of antagonism were verified in vitro and defined as competition and inhibition of mycelial growth. Sixty percent of the evaluated strains showed antagonistic potential and, among those, 24 strains expressed antagonism to both target fungi, with P. fluorescens being the most representative bacterial species. This work clearly identified a number of strains with potential for use as plant growth-promoting and biocontrol of the two soilborne fungal pathogens in vegetable crops production systems.
Afficher plus [+] Moins [-]RESPOSTA FUNCIONAL DA JOANINHA CRYPTOLAEMUS PREDANDO COCHONILHA BRANCA EM DIFERENTES TEMPERATURAS E SUBSTRATOS VEGETAIS Texte intégral
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.
Afficher plus [+] Moins [-]EFEITO RESIDUAL DA ADUBAÇÃO FOSFATADA EM TRÊS CULTIVOS SUCESSIVOS COM FEIJÃO - CAUPI Texte intégral
2014
JANDIÊ ARAÚJO DA SILVA | ADEMAR PEREIRA DE OLIVEIRA | MÁCIO FARIAS DE MOURA | JULIETE ARAÚJO DA SILVA | MARIA APARECIDA DE MOURA ARAÚJO
This study aims to provide doses of P 2 O 5 rates in Regolithic Neossoil, and evaluate the phos- phorus waste (P) in the soil and leaf content in three successive cowpea - beans crops. The experiment was car- ried out at field conditions, in Areia city – PB, in the period January to December 2007 in a randomized block with six treatments (0, 100, 200, 300, 400 and 500 kg ha - 1 P 2 O 5 ) and four replications. The first crop production variables (green beans per plant (PGVP), productivity of pods (PV) and dry beans (PGS) as a function of the above treatments, and in the last two harvests, the same variables in the production function were evaluated residual phosphorus in the soil. Phosphorus content after the first crop (49.53 mg dm - 3 ), corresponding to a residue (38.33 mg dm - 3 ) was higher initially to that in soil (11.2 mg dm - 3 ) before the first crop. Foliar - P for the highest values were observed for the first crop. Already the third crop, introduced himself as one of lower con- centration of P in the leaves, 1.56 g kg - 1 . The dose of 280 kg ha - 1 P 2 O 5 gave residue in P sufficient for the maxi- mum production of green beans per plant of 252 g, the second crop soil's estimated maximum yield of pods, 6.3 to 7.3 t ha - 1 at the first and second crops were obtained with Keywords : Vigna unguiculata . Phosphorus waste. yield.
Afficher plus [+] Moins [-]CULTIVO DA MAMONEIRA SOB DIFERENTES TIPOS DE ÁGUAS RESIDUÁRIAS E DE ABASTECIMENTO E NÍVEIS DE ÁGUA NO SOLO Texte intégral
2014
JOSILDA DE FRANÇA XAVIER | CARLOS ALBERTO VIEIRA DE AZEVEDO | NAPOLEÃO ESBERARD DE MACÊDO BELTRÃO | JOSELY DANTAS FERNANDES | VERA LÚCIA ANTUNES DE LIMA
The reuse of waters served in industries is winning space in the current days, in face of possibility of its use in agriculture. It was aimed with this work to evaluate the effect of levels of available water in the soil and of effluents of industries of supply Campina Grande, Paraíba state, Brazil, on the chemical attributes of the soil and on the phytomass and production variables of the castor oil plant, variety BRS Nordestina. The experiment was in greenhouse in entirely randomized design in factorial scheme 5 x 3 with 3 repetitions, with 5 water types and 3 available soil water levels. The studied treatments promoted increase in all soil chemical attributes at the end of the experiment. The interaction types of water and levels of available water in the soil was significant for all phytomass and production variables, except for the length of the root. The largest value for the phytomass and production variables was obtained for the treatment with 100% of available water in the soil and wastewater of COTEMINAS. however, the number of male flowers didn't suffer significant effect of the levels of available water of the soil with the wastewater of COTEMINAS.
Afficher plus [+] Moins [-]QUALIDADE PÓS-COLHEITA DE AMEIXAS ‘CAMILA’ E ‘LAETITIA’ COLHIDAS EM DIFERENTES ESTÁDIOS DE MATURAÇÃO Texte intégral
2014
MAYARA CRISTIANA STANGER | CRISTIANO ANDRÉ STEFFENS | CASSANDRO VIDAL TALAMINI DO AMARANTE | THAIS ROSELI CORRÊA | HÉLIO TANAKA
This work was carried out to investigate the effect maturity stage at harvest (M1, M2 and M3, corresponding to fruit with 20-25%, 45-50% and 70-75% of peel red color surface, respectively) of ‘Camila’ and ‘Laetitia’ plums, and then stored in conventional cold storage, on ripening and quality, especially regarding the incidence of flesh browning. Fruits were cold stored during 40 days (1±0.1 oC and 95±2% RH), followed by three days at ambient condition (23±5 °C and 60±5% RH). ‘Camila’ plums harvested at maturity stage M1 showed the poorest evolution of peel red color during cold storage. Only fruit harvested at stage M3 had a good flesh red color development. The values of flesh firmness and force for fruit compression were different be- tween maturity stages, being higher in M1 than in M2 and M3. On the other hand, fruit harvested at stage M1 had the highest force for flesh penetration. However, ‘Camila’ plums harvested with up to 50% of peel red color did not ripe satisfactory and had poor quality. ‘Laetitia’ plums showed satisfactory evolution of peel red color during cold storage, especially when harvested at stage M3. For this cultivar, the force for fruit compres- sion was different between maturity stages, in the following order: M1>M2>M3. Titratable acidity was highest in fruit harvested at stage M1, while ethylene production rate was highest for fruit harvested at stage M3. ‘Laetitia’ plums harvested at the three maturity stages had similar ripening during cold storage. However, fruits should not be harvested with 20-25% of peel red color since they will have a high intensity of flesh browning during cold storage.
Afficher plus [+] Moins [-]RACIONALIZAÇÃO DE PRODUTOS FITOSSANITÁRIOS PELA ADOÇÃO DA PRODUÇÃO INTEGRADA DE UVA NA REGIÃO DO VALE DO SUBMÉDIO DO SÃO FRANCISCO Texte intégral
2014
GEISA MAYANA MIRANDA DE SOUZA | RAISSA RACHEL SALUSTRIANO DA SILVA-MATOS | JOSÉ EUDES DE MORAIS OLIVEIRA | ANDRÉA NUNES MOREIRA | PAULO ROBERTO COELHO LOPES
The indiscriminate use of pesticides is a major environmental problems in the conventional agricultural production systems. The Integrated Production (IP) emphasizes the reduced use of pesticides based on monitoring of pests and diseases. This study aimed to quantify the percentage of reduction in pesticide use in vine growing companies in the region of the São Francisco Submédio Valley after the introduction of IP- Grape. For the survey data were used passbooks field of nine companies in the region checking the number of applications during the production cycle of the years 2006 to 2009, compared to when there was no IP-Grape. In 2006, 2007, 2008 and 2009 decline of 10, 20, 25 and 16% respectively, in the number of fungicide applica- tions, while the spraying of insecticides decreased 99, 95, 93 and 76%. Herbicides had the greatest rationaliza- tion (85%) in 2006, reaching 100% in 2007, 2008 and 2009, in other words from the year 2007. The rationali- zation in acaricides use was not recorded. Thus, the IP-Grape has achieved positive results in relation to the rational use of pesticides.
Afficher plus [+] Moins [-]MANEJO FITOTÉCNICO DA BANANEIRA, CULTIVAR D' ANGOLA (AAB), VISANDO AO CONTROLE DA SIGATOKA-NEGRA Texte intégral
2014
MARIA DE JESUS BARBOSA CAVALCANTE | ROMEU DE CARVALHO ANDRADE NETO | ANA DA SILVA LEDO | TARCÍSIO MARCOS DE SOUZA GONDIM | ZILTON JOSÉ MACIEL CORDEIRO
The objective of this work was to evaluate management systems for the control of Black Siga- toka in the cultivation of banana D'Angola cultivar. The experiment was installed and carried out at Embrapa Acre, Rio Branco - AC with the treatments distributed in randomized complete blocks with six replications consisting of different planting densities, corresponding to T1 - (1.111 plants ha-1; T2 - 1.666 plants ha-1; T3 - 2.000 plants ha-1; T4 - 1.333 plants ha-1; T5 - 2.500 plants ha-1 and; T6 - 1.111 plants ha-1 under rubber trees. The evaluations were carried out during two cycles of production. Plants of cv. D'Angola (AAB) cultivated in 3.0 x 3.0 m, shaded by the rubber trees, presented higher plant height, higher number of functional leaves at flowering and harvest, higher average bunch weight, greater weight of the bunches, longer cycle production and reduced severity of black sigatoka. Highest yields were obtained when we adopted higher densities. The banana intercropping with rubber trees proved to be a good alternative to permit cultivation of cv. D'Angola (long banana).
Afficher plus [+] Moins [-]SOIL EXCHANGEABLE ALUMINUM INFLUENCING THE GROWTH AND LEAF TISSUE MACRONUTRIENTS CONTENT OF CASTOR PLANTS Texte intégral
2014
ROSIANE DE LOURDES SILVA DE LIMA | LIV SOARES SEVERINO | GILVAN BARBOSA FERREIRA | CARLOS ALBERTO VIEIRA DE AZEVEDO | VALDINEI SOFIATTI | NAIR HELENA DE CASTRO ARRIEL
Three castor ( Ricinus communis ) genotypes were studied regarding tolerance to high exchange factorial distribution of five doses of exchangeable aluminum added to the soil (0, 0.15, 0.30, 0.60, and 1.20 cmol c dm - 3 ) and three castor genotypes (BRS Nordestina, BRS Paraguaçu, and Lyra). The plants were raised in pots in a greenhouse. At 53 days after emergence, data were taken on plant height, leaf area, dry mass of shoot and root, and leaf tissue content of macronutrients. The most sensitive genotype was the cv. BRS Nordestina, in which the shoot and root dry weight in the highest aluminum content were reduced to 12.9% and 16.2% of the control treatment, respectively. The most tolerant genotype was the hybrid Lyra, in which the shoot and root dry weight in the maximum content of aluminum were reduced to 43.5% and 42.7% of the control treatment, respectively.The increased exchangeable aluminum affected the leaf nutrient content, and the intensity of the response was different among cultivars. The aluminum toxicity increased N, Ca, and Mg contents and reduced on P, K, and S contents. The cv. BRS Nordestina had a drastic shoot dry weight reduction associated with an intense increment in the N leaf content. Thus, the N increment was caused by a concentration effect caused by the limited growth.
Afficher plus [+] Moins [-]ADUBAÇÃO FOSFATADA PARA A CULTURA DO GENGIBRE NA REGIÃO SERRANA DO ESPÍRITO SANTO Texte intégral
2014
ADEMAR ESPÍNDULA JÚNIOR | LÚCIA HELENA CUNHA DOS ANJOS | MARCOS GERVASIO PEREIRA | EVERALDO ZONTA | NILVADO SCHULTZ | RONI FERNADES GUARESCHI
The ginger culture was planted in Espirito Santo State on a commercial scale for just over 10 years as an alternative income for farmers family based submitted high yield potential, but requires studies to their best advantage due to the great variability of climatic conditions of the State. The aim of this study was to evaluate the yield of fresh rhizomes, the dry mass of leaves and rhizomes and the extraction and accumulation of N, P and K of the culture depending on the application of increasing doses of P, in a dystrophic Ultisol . The experiment was conducted on a farm in the municipality of Santa Maria de Jetibá (ES) between the months of August 2006 and June 2007. Experimental model adopted was randomized blocks with four treatments and four replications. The treatments consisted of control (no P fertilization), and doses of 60, 120 and 240 kg ha - 1 of P 2 O 5 applied at planting. The plants showed continuous growth up to 180 days after planting (DAP) and the phase of the plant where there was greater uptake of N, P and K in the flowering cycle was at 240 DAP. Analy- zing the contents of N, P and K, in the rhizome and leaves over the cultivation cycle, it was observed that, in general, most of the accumulation occurred in the rhizome.
Afficher plus [+] Moins [-]