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ATIVIDADE ENZIMÁTICA DE FUNGOS ENDOFÍTICOS E EFEITO NA PROMOÇÃO DO CRESCIMENTO DE MUDAS DE MARACUJAZEIRO-AMARELO
2006
Jaqueline Silva Luz | Roberta Lane de Oliveira Silva | Elineide Barbosa da Silveira | Uided Maaze Tiburcio Cavalcante
From leaves, stems and roots of healthy yellow passion fruit plants 93 isolates of endophytic fungi were obtained, with the colonization rates varying from 59.8 to 92.4% (leaves), 27.2 to 90% (stems) and 2.4 to 87.2 (roots). Twenty-nine of these isolates were evaluated for extracelular hydrolitic enzymes production (amylolitic, cellulolitic, lypolytic and proteolytic) and capacity to promove growth of yellow passion fruit seedlings. The isolates were identified as Fusarium (44.82%), Colletotrichum (37.93%), Acremonium, Glomerella, Curvularia, Alternaria and Aspergillus (3.45% each). The isolates EM11, EM50, EM172, EM20, EM81, EM72, EM135 and EM24 presented lypolytic activity with halos varying from 1.52 to 3.74 cm, and no isolate produced proteolytic, cellulolytic and amylolitic enzymes. Fifteen endophytic isolates promoted growth of yellow passion fruit seedlings, being the best EM173 (Alternaria), EM155 (Fusarium), EM139 (Curvularia), EM20 (Colletotrichum), EM6 (Acremonium) and EM151 (Colletotrichum) that increased aerial and root fresh biomass and root dry biomass of until 108.4, 204.4 and 70.2%, respectively, 90 days after the inoculation.
Afficher plus [+] Moins [-]NATUREZA E PARCELAMENTO DE NITROGÊNIO NA PRODUÇÃO E QUALIDADE DOS FRUTOS DO MELOEIRO
2006
Francisco Cardoso Neto | Hugo Orlando Carvallo Guerra | Lúcia Helena Garófalo Chaves
The objective of this work was to evaluate the effect of four nitrogen sources (ammonium sulfate, calcium nitrate, urea and monoammonium phosphate) at 80 kg ha-1, applied 2, 3, 4 and 5 times through drip irrigation on the production and characteristics of the melon, under field conditions, at the Cajazeiras Agricultural Farm, located in Tibau, RN, Brazil. The experiment was carried out in a completely randomized block design, in a 4 x 4 factorial scheme, with four replications. The melon yield was measured considering total number and weight of the fruits, the number of marketable fruits per hectare and size of the fruits. Generally speaking, the results showed that melon plants presented similar response to all used nitrogen sources, notably to the MAP applied three times; that the number of nitrogen applications did not affected the evaluated parameters regarding production and quality of fruits; and that the used nitrogen sources and the application number of the fertilizers resulted in higher amount of types 6, 7 and 8 fruits (fruits with average size).
Afficher plus [+] Moins [-]COMPETIÇÃO DE CULTIVARES DE ALFACE-AMERICANA NO SUL DE MINAS GERAIS
2006
Jony Eishi Yuri | Geraldo Milanez de Resende | José Hortêncio Mota | Rovilson José de Souza
Aiming to evaluate crisp head lettuce cultivars adapted to summer, showing tip burn¿s tolerance caused by calcium deficiency, an experiment was conducted in Santana da Vargem, MG, comprising the Lucy Brown, PSR 1114, PSR 1115, PSR 0110, PSR 5338, PSR 1530, PSR 0398 and Raider cultivars. A randomized complete blocks design with three replications was used. Total and commercial fresh mass, stem length and tip burn¿s tolerance caused by calcium deficiency were evaluated. The total fresh mass ranged between 538.8 and 894.4 g.plant-1, being PSR 1114; PSR 1115; PSR 5338 and Lucy Brown superior to the others, with 822.2; 833.3; 850.0 and 894.4 g plant-1, respectively. For commercial fresh mass and stem length there were no significant differences among the evaluated cultivars. Regarding tip burn¿s tolerance significant differences were observed. The Lucy Brown cultivar showed the highest incidence of this physiological disorder.
Afficher plus [+] Moins [-]INFLUÊNCIA DO SUBSTRATO NA EMERGÊNCIA DE PLÂNTULAS DE SAPOTA PRETA
2006
Inez Vilar de Morais Oliveira | Ítalo Herbert Lucena Cavalcante | Antonio Baldo Geraldo Martins
Aiming to evaluate seedling emergence of black sapote (Diospyros ebenaster Retz.) it was developed an experiment with seeds, collected on mature fruits, proceeding from Germoplasm Bank of Horticulture Department, University of São Paulo State, Jaboticabal, Brazil. Immediately after extracted, the seeds were washed, dried in paper and put in plastic box filled with the substrate studied, thus characterizing four treatments, as follows: Plantmaxâ; Coconut fiberâ; Sand; Soil mix [soil + sand + bovine manure (3:3:1)]. It was observed emergence percentage (E%) and rate of emergence speed (RES). The different substrates had statisticalinfluence on variable studied. The highest E% was obtained on soil mix, Plantmaxâ and Coconut fiberâ substrates and the best RES was observed on soil mix and Plantmax? substrates.
Afficher plus [+] Moins [-]MEDIDAS QUALITATIVAS DE CULTIVARES DE Panicum maximum JACQ. SUBMETIDOS A ADUBAÇÃO NITROGENADA
2006
Carla Giselly de Souza | Mércia Virgínia Ferreira dos Santos | Maria da Conceição Silva | Márcio Vieira da Cunha | Mário de Andrade Lira
This experiment was carried out in the greenhouse of the Departament of Animal Production/ UFRPE, from november of 2002 to may of 2003. The work objective was to evaluate the chemical composition of different Panicum maximum Jacq. cultivars submitted to different levels of nitrogen fertilization. It was used a complete randomized experimental design and the treatments were represented by the factorial arragement of the cultivars Massai, Atlas and Tobiatã and the nitrogen fertilization (0, 80, 160 and 320 kg of N.ha-1.year-1), with four replications. The plants were cut 60 days after-seeding for uniformization and three cuts were carried out with intervals of 35 days and intensity of 10 cm. It was determined concentration of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF). Massai presented lesser crude CP (12,7%) and greater NDF concentration (60,8%) than the other cultivars. There was significant effect of the nitrogen fertilization for the CP and NDF. The increase in the nitrogen level raised the CP concentration and reduced the FDN concentration of the studied plants. The Atlas may be considered the cultivar that presented the best chemical composition because its satisfactory CP concentration (15,3%) associate to the lesser NDF concentration (58,8%).
Afficher plus [+] Moins [-]ATIVIDADE MICROBIANA E DESENVOLVIMENTO DO MELÃO CULTIVADO SOB DIFERENTES PROPORÇÕES DE PÓ DE COCO
2006
José Maria Tupinambá da Silva Júnior | Vânia Felipe Freire Gomes | Paulo Furtado Mendes Filho
In agriculture practiced in Brazil, the branch of the horticulture is one of the prominences, in production and in exportation, being melon one of the more produced fruits, especially in Brazil¿s northeast. In this context, the use of a good quality substrate is essential for the development of the plants. In this study it was evaluated the growth of melon seedlings and the role of Arbuscular Mycorrhizal Fungi (AMF),Glomus clarum, associated to the use of coconut dust, as an alternative substrate, at 100, 80, 60, 40, 20, 10 and 0% concentrations, as a soil mixture (grayish Argissol). The plants were cultivated under greenhouse conditions and, at the end of a 35 days period, were analyzed the diameter of the stem, number of leaves, height of plants, shoot dry weight, microbial biomass carbon content, basal soil respiration, metabolic quotient, colonization with AMF and shoot nutrient content (N, P, K, Ca and Mg). It was observed that 100% and 80% concentration of coconut dust were the more restrictive treatments for plant development. Microbial carbon and mycorrhizal colonization were higher when the substrate was composed by 10 and 20% of coconut dust. The basal soil respiration and the metabolic quotient (2,07) were higher when 100% coconut dust was used, while the smallest value (0, 96) was found in treatment without coconut dust. The use of concentrations higher than 40% of coconut dust decreased AMF activity and growth of the melon plants.
Afficher plus [+] Moins [-]ADUBOS VERDES NA FITORREMEDIAÇÃO DE SOLOS CONTAMINADOS COM O HERBICIDA TEBUTHIURON
2006
Fábio Ribeiro Pires | Sergio de Oliveira Procópio | Caetano Marciano de Souza | José Barbosa dos Santos | Gilson Pereira Silva
The tebuthiuron residue, used in the sugar-cane culture, can be found in soil until two or more years after its application. Recent researches are being done using the phytoremediation in the attempt of removing it from the soil. The purpose of this work was to evaluate the effectiveness of the green manure use in the phyitoremediation of the tebuthiuron herbicide. The evaluated species were: Cajanus cajan, Canavalia ensiformis, Dolichos lablab, Pennisetum glaucum, Estizolobium deeringianum, Estizolobium aterrimum and Lupinus albus. These were sown and cultivated in pots containing soil treated with different doses of tebuthiuron (0.0; 0.5; 1.0; and 1.5 kg.ha-1). A control treatment without green manure, submitted to the same dosages, was kept. Sixty days after planting, green manure aerial part of all plants were harvested and soybean was sowed in the same pot, to bioassay accomplishment. Sixty days after sowing, the soybean plants were harvested, being the following evaluations carried out: height of plants, phytotoxicity symptoms and plants above ground dry biomass and leaf area. Until 0.5 kg.ha-1 tebuthiuron dosage, the species that better phytoremediated this herbicide was L. albus. When the soil was treated with tebuthiuron at 1.0 kg.ha-1, the C. ensiformis, followed by L. albus and S. aterrimum, they were the treatments that better phytoremediated tebuthiuron because results in highest plant height, above ground dry biomass and lesser phytotoxicity symptoms and still the biggest foliar area of the soybean plants. When the tebuthiuron was applied at 1.5 kg ha-1 dosage, it was impossible to evaluate the phyitoremediation, as the tested plants were eliminated.
Afficher plus [+] Moins [-]INFLUÊNCIA DO HORÁRIO DE CORTE NA PRODUÇÃO DE ÓLEO ESSENCIAL DE CAPIM-SANTO (ANDROPOGUM SP)
2006
Iarajane Bezerra do Nascimento | Renato Innecco | Sérgio Horta Matos | Neiliane Sampaio Sombra Borges | Cláudia Araújo Marco
The objective of this work was to evaluate the effect of cut-time on lemon grass essential oil yield and on its constituent citral contents. A completely randomized design with four replications was used. Six cuttimes were studied: 7:00, 9:00 and 11:00 AM, 1:00, 3:00 and 5:00 PM. The analyzed variables were essential oil yield and relative citral contents. The highest essential oil yield was obtained when cut occurred at 7:00 AM. The highest citral contents was obtained when cut occurred at 1:00 PM, but was not statistically different from those obtained at 7:00, 9:00 and 11:00 AM, and 3:00 PM. Lemon-grass must be harvested between 9:00 and 11:00 AM in order to obtain maximum essential oil yield and maximum citral contents.
Afficher plus [+] Moins [-]IMPROVING MASS REARING TECHNOLOGY FOR SOUTH AMERICAN FRUIT FLY (DIPTERA:TEPHRITIDAE)
2006
Raimundo Braga Sobrinho | Carlos Caceres | Amirul Islam | Vivat Wornoayporn | Walter Enkerlin
Studies on availability of suitable and economic diets for adults and larvae of the South American fruit fly Anastrepha fraterculus (Wiedemann, 1830) were carried out at the Entomology Unit of the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria with the aim to find the best diets to fit in a large scale mass rearing production. The best diet for adult was the combination of Hydrolysate Corn Protein + Yeast Hydrolysate Enzymatic + Sugar (3:1:3). This diet resulted in the highest numbers of egg/female/day, spermatozoid in the spermathecae, percentages of egg hatch, the lowest mortality rate of adults and the highest average mating duration compared with the standard adult diet based on Yeast Hydrolysate Enzymatic + Sugar (1:3). Among eleven larval diets tested, diets based on sugarcane and sugarbeet bagases plus 7% brewer yeast, 8% sugar, 0.2% sodium benzoate, 0.8% of hydrochloric acid and 60% water (adjusted), yielded the highest percentages of egg hatching, pupal recovery, pupal weight and adult emergence. There was no statistical difference with the standard larval diet based on wheat germ 3%, corncob 15%, corn flower 8%, brewer yeast 6%, sugar 8%, sodium benzoate 0.23%, hydrochloric acid 0.63%, nipagin 0.14% and water 59% (adjusted). The significant performance of these adult and larval diets open discussion for future researches on improvement of rearing techniques required for the establishment of sterile insect technique (SIT) program focused on the South American fruit fly.
Afficher plus [+] Moins [-]EFEITO DA TEMPERATURA E DA LUZ NAS SEMENTES DE COPAIFERA LANGSDORFII DESF.
2006
Maria Elane de Carvalho Guerra | Sebastião Medeiros Filho | Elizita Maria Teófilo
Copaifera langsdorfii is a typical tree species very important for restoration of degraded areas. This study evaluated the effect of different temperatures and light conditions on Copaifera seed germination. The applied treatments were the temperatures of 25ºC, 30ºC and 20-30ºC and three different light expositions (constant dark, 8h of light plus 16h of dark and constant light). The tested variables were percentage, velocity and average time of germination. The treatments consisted of 200 seeds, with four replications of 50 seeds each, sown on a Germitest towel paper and maintained for 28 days on germination chamber. The completely randomized design was used and the averages compared by Tukey test at 5% probability. Germination percentage was not influenced by the treatments. The constant temperatures of 25ºC or 30ºC, independently of light regime, promoted a higher rate of germination velocity and caused the reduction of the germination average time.
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