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ATRIBUTOS FÍSICO-HIDRICOS E CARBONO ORGÂNICO DE UM ARGISSOLO APÓS 23 ANOS DE DIFERENTES MANEJOS
2012
CLÉRIO HICKMANN | LIOVANDO MARCIANO DA COSTA | CARLOS ERNESTO GONÇALVES REYNOUD SCHAEFER | RAPHAEL BRAGANÇA ALVES FERNANDES | CAMILO DE LELLIS TEIXEIRA ANDRADE
Due to continued machinery, soil mobilization has caused considerable changes in both soil bulk density (physical attributes) and organic C content, risking crop yield reduction and negative environmental effects. In this context, this work aimed at assessing changes in both physical attributes and in organic C content of a Argissolo Vermelho-Amarelo surface horizon, subjected to no-tillage (NT) and conventional tillage with disk plow (DP), heavy harrow (HG), and disc plow plus harrow (DP+HG) for 23 years. A natural forest fragment (NF) was used as reference area. A randomized-block design with 8 x 12 m plots and four replications was used. Soil samples were collected at 0-5, 5-10, 10-20, and 20-40 cm depths in order to assess soil density, total organic carbon content, porosity, saturated hydraulic conductivity, and aggregate stability. Results showed that continued cultivation increases soil physical degradation, as evidenced by both macro porosity and total porosity reduction, aggregate stability, saturated hydraulic conductivity, total organic carbon, and soil density increase. The NT was found to best contribute to soil physical properties improvement and total organic carbon recovery in 0-5 cm surface layer.
Afficher plus [+] Moins [-]COMPOSIÇÃO QUÍMICA E MICROBIOLÓGICA DE BIOFERTILIZANTES EM DIFERENTES TEMPOS DE DECOMPOSIÇÃO
2012
SAULO DE TARCIO PEREIRA MARROCOS | JOSÉ NOVO JUNIOR | LEILSON COSTA GRANGEIRO | MÁRCIA MICHELLE DE QUEIROZ AMBROSIO | ANA PAULA ALVES DA CUNHA
The objective of this work was to evaluate the chemical composition and microbial of biofertilizers at different decompositions times. For this, we used biofertilizers two. The experimental designused was entirely randomized in factorial scheme 2x7 two sources of manure (cattle and chicken) and seven times of decomposition (0, 5, 10, 15, 20, 25 and 30 days), with three replications. We evaluated the chemical parameters (pH, CE, dry mass, N, P, K, Ca and Mg) and microbiological (bacteria, fungi and actinomycetes total). The chicken manure gave significant increase of nitrogen, phosphorus and potassium, dry mass and electrical conductivity. The highest concentration was within 15 to 20 days of decomposition, with the exception of nitrogen, with the highest concentration on the preparation of biofertilizer. In the microbiological analysis, the chicken manure resulted in higher total population of microorganisms (bacteria, fungi and actinomycetes total) compared to beef. The decomposition periods of biofertilizers influence on nutrient levels, diversity and populations of microorganisms.
Afficher plus [+] Moins [-]EFEITO DA ESTERILIZAÇÃO DO SUBSTRATO SOBRE O CRESCIMENTO DE MUDAS DE MELOEIRO EM PRESENÇA DE FUNGOS MICORRÍZICOS ARBUSCULARES E COMPOSTOS ORGÂNICO
2012
JOSÉ MARIA TUPINAMBÁ DA SILVA JÚNIOR | PAULO FURTADO MENDES FILHO | VÂNIA FELIPE FREIRE GOMES | FRANCISCO VALDEREZ AUGUSTO GUIMARÃES | ELISANGELA MARIA DOS SANTOS
In order to determine the effect of organic fertilizer on growth of seedlings of melon inoculated with arbuscular mycorrhizal fungi (AMF), an experiment was conducted under greenhouse conditions. The experimental design adopted was a completely randomized design with four treatments and four replications. Treatments consisted of melon plants cultivated on sterile and non sterile soil in the presence or absence of organic compost. The melon seeds were germinated in trays containing substrate formed by 70% of Soil + 30% of green coconut powder, and the mycorrhizal inoculation used a mixture of the species Glomus clarum and Glomus intraradices, applied at the time of sowing. The seedlings with the first definitive sheet were transplanted into pots with sterile or non sterile soil, fertilized or not with organic compost. After 30 days from transplanting plants were harvested for determining the weight of fresh and dry shoot, stem diameter, arbuscular mycorrhizal colonization and content of macro and micronutrients. Organic compost addition did not influence arbuscular mycorrhizal activity and also increased shoot dry weight. AMF colonization of roots showed influence on macro (N, P and Ca) and micronutrients (Fe and Mn) shoot content on soil sterile with organic compost.
Afficher plus [+] Moins [-]CRESCIMENTO INICIAL DO PINHÃO-MANSO (Jatropha curcas L.) EM FUNÇÃO DA IRRIGAÇÃO, ADUBAÇÃO ORGÂNICA E COBERTURA DO SOLO
2012
JORGE ALVES DE SOUSA | HUGO ORLANDO CARVALLO GUERRA
The aim of the present paper was to evaluate the Jathropa curcas L response to different doses of nitrogen, water regimes and soil surface nature. The experiment was conducted from May 2009 to February 2010 under greenhouse conditions at the Sustainable Development Center of the Federal University of Paraiba in Sumé-PB. A factorial experiment in blocks was used with four organic fertilizer (0, 50, 100 and 150 kg of N/ ha), four irrigation levels (50, 75, 100 and 125% the Class A pan evaporation) and four additional treatments with soil mulching. Sixty plastic vases 100 l capacity were used to cultivate the plants during 257 days and a Class A Evaporation Pan was installed in the greenhouse to monitor daily water evaporation. The plant variables evaluated were plant height, stem diameter, leaf area, total aerial and root dry mass. The increase of the soil water content and soil mulching had significant effect on the evaluated plant variables.
Afficher plus [+] Moins [-]SEED INOCULATION WITH Azospirillum brasilense, ASSOCIATED WITH THE USE OF BIOREGULATORS IN MAIZE
2012
ALESSANDRO DE LUCCA E BRACCINI | LILIAN GOMES DE MORAES DAN | GLEBERSON GUILLEN PICCININ | LEANDRO PAIOLA ALBRECHT | MAURO CEZAR BARBOSA | ALEX HENRIQUE TIENE ORTIZ
The inoculation of seeds with the bacterium Azospirillum has been carried out in maize culture and other grasses. The application of growth bio-regulators is another technology whose results in maize culture have yet to become more widespread. Current study evaluates the agronomic effectiveness of seed inoculation with Azospirillum brasilense in maize, associated with the use of the growth regulator Stimulate ®. Triple hybrid maize CD 304 underwent the following treatments: 1 - control without nitrogen and without Azospirillum brasilense; 2 - Treatment without nitrogen but with Azospirillum brasilense; 3 - Treatment without nitrogen but with Azospirillum brasilense + Stimulate ®; 4 - Treatment with 50% of nitrogen dose recommended for maize culture; 5 - Treatment with 50% of nitrogen dose and inoculation with Azospirillum brasilense; 6 - Same as 5 but with Stimulate ®; 7 - Total N recommended; 8 - Total N recommended + Azospirillum brasilense ; 9 - Total N recommended + Azospirillum brasilense + Stimulate ®. The inoculation of maize seeds with Azospirillum brasilense increases plant height and grain yield when compared with rates in control. The use of 50% of N dose in sowing, associated with the inoculation of maize seeds with Azospirillum brasilense at 200 mL ha-1 (mixed to the seeds) and associated with Stimulate ® (in foliar application), is viable.
Afficher plus [+] Moins [-]DURAÇÃO DO PERÍODO PRÉ-IMAGINAL E FECUNDIDADE DE Chrysoperla externa (HAGEN, 1861) (NEUROPTERA: CHRYSOPIDAE) EM DIFERENTES POPULAÇÕES E GERAÇÕES
2012
SERGIO ANTONIO DE BORTOLI | RAIMUNDO JOSÉ FERREIRA | ALESSANDRA MARIELI VACARI | CAROLINE PLACIDI DE BORTOLI | GUSTAVO OLIVEIRA DE MAGALHÃES | WANDERLEI DIBELLI
The lacewings appear in many agroecosystems, preying several species of agricultural pests. They have great search capability, high voracity, high reproductive potential and are easily maintained in laboratory conditions. In laboratory rearing, to avoid problems in the mass production are recommended adjustments in the type and quality of prey to be used in order to obtain individuals with desirable characteristics. It is necessary special care with the laboratory populations, avoiding problems from inbreeding. Larvae were reared individually in Petri dishes (9.0 cm diameter) and fed with eggs of Sitotroga cerealella (Olivier, 1789) (Lepidoptera: Gelechiidae), in the amount of 25 mg / larva, while the adults were kept in PVC cylindrical cages (10 cm x 30 cm). Thus, the study analyzed the influence of the size of the population of Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) on the pre-imaginal period (egg to adult) and reproductive capacity of this specie come from different populations and generations of laboratory. To this end, we used two populations, one of Jaboticabal (F8 and F21) and one of Piracicaba (F6 and F15), and subpopulations of 1, 5, 10, 15 and 20 couples, analyzing the incubation of eggs and the number of eggs per female in each population, generation and subpopulation. The pre-imaginal period (egg to adult) and the number of eggs per female of C. externa are influenced by the generation and the number of founding individuals, being these parameters favored when laboratory populations are established with the largest number of couples.
Afficher plus [+] Moins [-]DOSES DE NITROGÊNIO E FÓSFORO PARA A PRODUÇÃO ECONÔMICA DA MAMONEIRA NO MUNICÍPIO DE MOSSORÓ-RN
2012
ANTONIA ROSIMEIRE DA CRUZ SILVA | FÁBIO HENRIQUE TAVARES DE OLIVEIRA | ADELSON PAULO DE ARAÚJO | JOSÉ FRANCISMAR DE MEDEIROS | EVERALDO ZONTA
The fertilization of the castor bean plant (Ricinus communis L.) is few studies in the Northeast, where soils are generally poor in nitrogen (N) and phosphorus (P). This work aimed to define the doses of N and P2O5 associated with maximum economic production of castor beans cultivar BRS Energia and critical levels of N and P in castor bean leaf and the critical level of P available in an Oxisols. The experimental design was a randomized block in factorial 4 x 4 with four replicates, combining four N rates (0, 45, 70 and 120 kg ha-1) with four P2O5 rates (0, 30, 60 and 120 kg ha-1). The castor bean plant was planted at a spacing of 0,90 x 0,50 m under rainfed conditions with supplementary irrigation. At the end of the experiment, was evaluated the overall productivity and productivity racemes primary, secondary and other. The higher net income was estimated to productivity of 2.304 kg ha-1 grain, obtained by applying the doses of 120 kg ha-1 of N + 120 kg ha-1 of P2O5. The critical levels of N and P in the leaf were 37,5 g kg-1 and 2,4 g kg-1, respectively, and the critical level of available P in soil by Mehlich-1 extractor was 7,0 mg dm-3.
Afficher plus [+] Moins [-]VIDA ÚTIL PÓS-COLHEITA DE CINCO HIBRIDOS DE MELÃO AMARELO PRODUZIDOS NO AGROPÓLO MOSSORÓ-ASSU
2012
EDNA MARIA MENDES AROUCHA | HÉLIDA CAMPOS DE MESQUITA | MARCELO SOBREIRA DE SOUZA | WEDSON DE LIMA TORRES | RAFAELLA MARTINS DE ARAÚJO FERREIRA
The goal of this paper is to evaluate the shelf-life of five yellow melon hybrids (AF-5107, AF6742, AF-9136, AF and AF-6798-7719) produced in the Mossoró-Assu agropole. The yellow melon hybrids were grown in soil fertilized and irrigated following the demand of culture. Reaching the stage of commercial maturity, fruit were harvested and brought to the Postharvest Laboratory at the Universidade Federal Rural do Semi-árido, where were taken12 fruits at random for characterization of each hybrid at time zero. Afterwards the other fruits were weighed, identified and stored in cold room regulated at 10 ± 1 ºC and 90 ± 2% RH, where they remained for 14, 21, 28, 35, 42 and 49 days. At each time interval, the following analyses were realized: mass loss, external and internal appearance, pulp firmness and soluble solids. The experimental design was completely randomized in factorial scheme 5 x 7, five hybrids and seven periods of storage. We used four replications, and the experimental unit consists of three fruits. There was significant interaction between hybrid and storage period only for the soluble solids. For the other characteristics evaluated, we observed the isolated effect of the main factors. The hybrid AF-9136 stood out compared to other hybrids tested by greater pulp firmness and soluble solids.
Afficher plus [+] Moins [-]CRESCIMENTO E DESEMPENHO DE BERTALHA (Basella alba L.) EM FUNÇÃO DO TIPO DE PROPAGAÇÃO
2012
RENÊ ARNOUX DA SILVA CAMPOS | GIUSEPPINA PACE PEREIRA LIMA | SANTINO SEABRA JÚNIOR | WILLIAM HIROSHI SUEKANE TAKATA | EWERTON GASPARETTO DA SILVA
Malabar spinach is a non-conventional vegetable propagated mainly by seeds. This research evaluated the propagation by stem cuttings as an alternative method of propagation and verified its effect on growth of the vegetable. Plantlets propagated by seeds and stem cuttings were grown in greenhouse and their growth were evaluated in five successive intervals of 21 days each, with the first evaluation carried out 60 days after the transplanting. The results showed that the propagation methods have influence on the Malabar spinach growth. Plants propagated by seeds display slow, but vigorous growth, with larger relative yield of leaves and tender leaves, while plants propagated by cuttings showed fast initial growth, with rapid fruit formation. Thus, the propagation by cuttings is more suitable for seed production, while propagation by seeds is more profitable for leaves production.
Afficher plus [+] Moins [-]PRODUÇÃO E QUALIDADE DE MELÃO RENDILHADO SOB DIFERENTES SUBSTRATOS EM CULTIVO PROTEGIDO
2012
DANILO MESQUITA MELO | RENATA CASTOLDI | HAMILTON CÉSAR DE OLIVEIRA CHARLO | FRANCINE DE SOUZA GALATTI | LEILA TREVISAN BRAZ
This paper aimed to evaluate the performance of hybrids of muskmelon on different substrates. Five substrates were evaluated: S1 = coconut husk fiber, S2 = sand; S3 = ½ sand and ½ crushed of sugarcane, S4 = ½ sand and ½ of peanut shell, and S5 = I sand, I of crushed sugarcane and I of peanut shell and four hybrids of muskmelon (Bonus N°. 2, Louis, Fantasy Jab and 2007 # 16). The plants were cultivated in plastic pots of 13 dm3, which were filled with these substrates; they were arranged in plants spacing of 1,0 x 0,5 m between plants. The Fertirrigation was done by dripping, using a nutrient solution for the culture. The experimental design was a randomized blocks, in a 5 X 4 factorial design with four replications. The characteristics evaluated were: total production, average transverse and longitudinal diameter of fruit, fruit shape index; mesocarp thickness; average transverse and longitudinal diameter of the locule; index format locule; mass of fresh fruit; soluble solids, pH; titratable acidity; C vitamin; firmness of flesh; tracery of shell; and maturation index. The optimal substrate for muskmelon cultivation is a combination of 50% sand + 50% peanut shell. The hybrid Fantasy performed better compared to other hybrids.
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