oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Gossipium hirsutum L. extract as green corrosion inhibitor for aluminum in HCl solution
Olusegun K. Abiola, E.M. Odin, D.N. Olowoyo, T.A. Adeloye
Bulletin of the Chemical Society of Ethiopia , 2011,
Abstract: Inhibitive effect of Gossipium hirsutum L. leaves extract on the acid corrosion of aluminum in 1 M HCl solution was studied by weight loss technique. The extract at optimum concentration inhibited the corrosion of aluminum, with about 92% inhibition efficiency and the inhibition efficiency increased with increasing concentration of the extract at 30 oC. The results obtained revealed that the adsorption of the inhibitor molecule onto metal surface accords with Lanqmuir adsorption isotherm. KEY WORDS: Aluminum, Gossipium hirsutum L., Weight loss, Acid corrosion, Acid inhibition Bull. Chem. Soc. Ethiop. 2011, 25(3), 475-480.
Gossipium hirsutum L. extract as green corrosion inhibitor for aluminum in HCl solution
Olusegun K. Abiola,E.M. Odin,D.N. Olowoyo,T.A. Adeloye
Bulletin of the Chemical Society of Ethiopia , 2011,
Abstract: Inhibitive effect of Gossipium hirsutum L. leaves extract on the acid corrosion of aluminum in 1 M HCl solution was studied by weight loss technique. The extract at optimum concentration inhibited the corrosion of aluminum, with about 92% inhibition efficiency and the inhibition efficiency increased with increasing concentration of the extract at 30 oC. The results obtained revealed that the adsorption of the inhibitor molecule onto metal surface accords with Lanqmuir adsorption isotherm.
Selección y caracterización de rizobacterias promotoras de crecimiento vegetal (RPCV) asociadas al cultivo de algodón (Gossypium hirsutum)  [cached]
Guzmán Andrés,Obando Melissa,Rivera Diego,Bonilla Ruth
Revista Colombiana de Biotecnología , 2012,
Abstract: Título en ingles: Selection and characterization of plant growth promoting rhizobacteria (PGPR’s) associated with cotton crop (Gossypium hirsutum) Resumen: Como parte de las estrategias de una agricultura sostenible, se hace necesario disminuir el uso de fertilizantes nitrogenados de síntesis, mediante la utilización de los biofertilizantes. En particular, los géneros Azotobacter y Azospirillum son utilizados como agentes promotores de crecimiento vegetal debido a su capacidad para fijar nitrógeno atmosférico y producir hormonas de tipo indólico. Por tal razón, en este estudio se aislaron bacterias diazotróficas de los géneros Azotobacter y Azospirillum a partir de la rizósfera de cultivos de algodón en el Espinal (Tolima). Las poblaciones microbianas se caracterizaron fenotípicamente en los medios de cultivo semiespecíficos: Ashby y LG (Azotobacter sp.) y NFb, LGI y Batata (Azospirillum sp.). La promoción de crecimiento vegetal se determinó mediante la actividad de la enzima nitrogenasa por medio de la técnica de reducción de acetileno y producción de índoles por el método colorimétrico de Salkowsky. Se obtuvieron 9 aislamientos tentativos de Azotobacter sp. y 4 de Azospirillum sp. Se presentaron diferencias significativas en la prueba de reducción de acetileno con las cepas presuntivas de Azotobacter sp.: NAT 9 (206.43 nmol C2H2 mL-1.h-1), NAT 4, (292.77 nmol C2H2 mL-1.h-1), y NAT 6 (460.60 nmol C2H2 mL-1.h-1) y en la producción de índoles de las cepas NAT 19 (19.87 μg.mL-1) y NAT 13 (20.08 μg.mL-1). Por su eficiencia in vitro en la promoción de crecimiento vegetal se seleccionaron las cepas NAT9, NAT4, NAT6, NAT19 y NAT13 para ser evaluadas como principio activo en futuros inoculantes para el algodón en esta zona del departamento del Tolima. Palabras clave: fijación biológica de nitrógeno; producción de índoles; promoción del crecimiento vegetal; biofertilizantes. Abstract: As part of strategies for sustainable agriculture, it is necessary to reduce the use of synthetic nitrogen fertilisers through the use of biofertilisers. In particular, the genera Azotobacter and Azospirillum are used as plant growth promoters because of their ability to fix atmospheric nitrogen and indolic type hormones. For this reason, in this study were isolated diazotrophic bacteria of the genera Azotobacter and Azospirillum from the rhizosphere of cotton crops in Espinal (Tolima). The microbial populations were characterized phenotypically in specific semi culture media: Ashby and LG (Azotobacter sp.) and NFb, LGI and Batata (Azospirillum sp.). The promotion of plant growth
SELETIVIDADE DE INSETICIDAS AO COMPLEXO DE INIMIGOS NATURAIS NA CULTURA DO ALGOD O (Gossypium hirsutum L.) SELECTIVITY OF INSECTICIDES ON THE COMPLEX OF NATURAL ENEMIES IN COTTON CROP (Gossypium hirsutum L.)  [cached]
Cecilia Czepak,Paulo Mar?al Fernandes,Karina Cordeiro Albernaz,Ohana Daroszewski Rodrigues
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v35i2.2260
Abstract: Avaliou-se a seletividade de inseticidas sobre o complexo de inimigos naturais na cultura do algod o (Gossypium hirsutum L.), no município de Goiania, GO. Utilizou-se a cultivar Deltapine e o delineamento experimental em blocos ao acaso, com sete tratamentos e quatro repeti es. Os tratamentos foram: testemunha, thiamethoxam (300 g.ha-1), lufenuron (300 mL.ha-1), betacyflutrin (800 mL.ha-1), imidacloprid (70 g.ha-1), diflubenzuron (6,0 g.ha-1), endosulfan (1500 mL.ha-1), em suas apresenta es comerciais. A pulveriza o dos inseticidas foi efetuada aos 45 dias após a emergência das plantas. Além da avalia o prévia, foram efetuadas avalia es aos três e sete dias após a aplica o dos inseticidas. As amostragens foram realizadas através do método de batida de pano, com duas batidas ao acaso por parcela, identificando-se e contando-se, o número de inimigos naturais presentes. Três dias após a aplica o dos tratamentos, os inseticidas thiamethoxam (300 g.ha-1), lufenuron (300 mL.ha-1) e diflubenzuron (60 g.ha-1), considerando os produtos comerciais, n o apresentaram efeito de choque sobre o complexo de inimigos naturais presentes na cultura do algodoeiro. Entretanto, aos sete dias após a aplica o, apenas o tratamento com lufenuron manteve a seletividade.a esses artrópodes predadores. PALAVRAS-CHAVE: Inseticida; controle biológico; Gossypium. The selectivity of insecticides was evaluated in the complex of natural enemies of the cotton (Gossypium hirsutum L.) crop. The cultivar Deltapine was used in a randomized block experimental design, with seven treatments and four replications. The treatments, all in their commercial formulation, were: control; thiamethoxam (300 g.ha-1); lufenuron (300 mL.ha-1); betacyflutrin (800 mL.ha-1); imidacloprid (70g.ha-1); diflubenzuron (6,0 g.ha-1); and endosulfan (1500 mL.ha-1). The insecticides were sprayed at 45 days after germination. Besides the initial evaluation, other evaluations were performed three and seven days after insecticide application. Each plot was sampled by the fabric beating method, with two random beatings per plot. Natural enemies were identified and counted. Three days after application, the insecticides thiamethoxam (300 g.ha-1), lufenuron (300 mL.ha-1), and diflubenzuron (60 g.ha-1) did not showed negative effect on the complex of predators present in the cotton. However, seven days after application, only the lufenuron treatment maintained the selective effect over predator complex. KEY-WORDS: Insecticide; biological control; Gossypium.
Comparación de ocho índices para determinar estabilidad fenotípica en algodón (Gossypiun hirsutum L.)  [cached]
Vertel Melba,Espitia Miguel,Martinez Ricardo
Agronomía Colombiana , 1999,
Abstract: EI presente trabajo se realizo para determinar el nivel de correlación lineal y de rango entre ocho índices que estiman estabilidad fenotípica. Para ella, se utilizaron los datos de rendimiento de fibra (RENDF) de 16 genotipos de algodón evaluados en 18 ambientes representativos del área algodonera del Caribe Colombiano, empleando los parámetros propuestos por Eberhart y Russel (bit S2di), Tai (αi y λi), Shukla (σ2j), Wricke (Wi), Plaisted y Peterson(σ2va ) y la varianza a través de los ambientes (S2i). Los resultados se alaron diferencias altamente significativas para ambientes, genotipos e interacción G*A. En general, los genotipos más rendidores fueron los menos estables. Se detecto correlación lineal significativa (P<0.01) alta (r>0.78) y positiva entre el RENDF, S2i ,bit αi. Entre S2di, λi, σ2i' Wi y σ2va se presentan correlaciones altas (r>0,94) y altamente significativas e inversas. EI RENDF mostro correlación de rango alto (r>0,73), significativa (p<0,01) y de sentido inverso con S2i, bi Y αi. Concordancias en la selección de los genotipos par su estabilidad fueron detectadas para con S2i, bi Y αi (r=0,97); lo mismo ocurrió entre S2di, λi, σ2i' Wi y σ2va (r>0,92). Palabras claves: Interacción genotipo por ambiente, rendimiento de fibra, varianza genotípica, varianza ambiental, correlaci6n de rango.
Parámetros agrícolas de ocho cultivares de algodón (Gossypium hirsutum) obtenidos en Cuba
Vinent,Enrique; Fajardo,Odelín;
Ciencia e investigación agraria , 2007, DOI: 10.4067/S0718-16202007000200008
Abstract: the correlations of the following variables were determined for eight cultivars of cotton (gossypium hirsutum) obtained in cuba: feather and raw cotton yields, boll weight, plant height and plant perimeter and the number of bolls per plant. feather and raw cotton yields were negatively correlated with plant height; in this same way, plant height and plant perimeter correlated with the number of harvested bolls per plant. boll weight did not correlate with the studied variables. by means of applying multivariate analysis techniques and variance analysis, promising cultivars were selected. significant differences were obtained among cultivars using seven biological parameters: feather and raw cotton yields, plant height and plant perimeter, ginning rate, boll weight and the number of harvested bolls per plant. the highest feather and raw cotton yields (5,575 y 2,353 kg?ha-1, respectively) were achieved with the cultivar l-48, followed by the cultivars l-3, l-6 and l-44 and the highest ginning rate (42%) was achieved with l-48. in conclusion, cotton cultivars l-48; l-3; l-6 and l-44 were the most promising cultivars, and will be further tested under commercial conditions
CORRELACIONES Y ANáLISIS DE SENDERO EN ALGODóN (Gossypium hirsutum L.) EN EL CARIBE COLOMBIANO CORRELATIONS AND PATH ANALYSIS IN COTTON (Gossypium hirsutum L.) IN THE COLOMBIAN CARIBBEAN  [cached]
Miguel Mariano Espitia Camacho,Hermes Araméndiz Tatis,Jorge Cadena Torres
Revista Facultad Nacional de Agronomía, Medellín , 2008,
Abstract: El cultivo del algodón es la principal actividad agrícola en la economía del Caribe colombiano en el segundo semestre del a o y el principal abastecedor de fibra a la industria nacional desde hace aproximadamente 60 a os. El objetivo de este trabajo fue estimar las correlaciones fenotípicas, genéticas y ambientales, entre 11 caracteres agronómicos y realizar un análisis de sendero para rendimiento de fibra. Se utilizaron los datos de la evaluación agronómica de 10 genotipos de algodón en ocho ambientes del Caribe colombiano. En cada ambiente se utilizó un dise o experimental de bloques completos al azar con cuatro repeticiones. Los resultados indicaron que las correlaciones genéticas fueron superiores a las fenotípicas y ambientales. El rendimiento de fibra (REF) presentó las mayores correlaciones fenotípicas, genéticas y fenotipicas parciales con el porcentaje de fibra (PFI), el rendimiento de algodón - semilla (RAS) y el peso de mota (PMO), con valores de r > 0,43 (P<0,01). El PFI (efecto directo de rG: 0,810) fue la variable causa que mostró el mayor efecto directo sobre el REF. El PFI puede ser usado como criterio de selección para incrementar el REF en algodón. The cotton crop is the main agricultural activity in the economy of the colombian Caribbean in the second semester of the year and the main supplier of fibre to national industry for about 60 years. The objective of this work was to estimate the phenotypic, genetic and environmental correlations, between 11 agronomic characters and to make a path analysis for fibre yield. Data of agronomic evaluation of 10 genotypes of cotton in eight environments of the colombian Caribbean were used. In each environment experimental design at random complete blocks with four repetitions were used. The results indicated that genetic correlations were superior to phenotypic and environmental correlations. Fibre yield (FIY) presented the highest phenotypic, genetic and partial phenotypic correlations with ginning percentage (GP), seed-cotton yield (SCY) and boll weight (BOW) with values of r > 0,43 (P<0,01). The FIP (0,810) was the cause variable that showed the greatest direct effect on the REF. The YFI can be used as selection criteria to increase the YFI in cotton.
Efecto de tres frecuencias de riego sobre el rendimiento de algodón en rama y sus componentes en cuatro cultivares de algodón (Gossypium hirsutum L.) tipo upland
Méndez-Natera,J.R; Salazar-Brito,R.S; Merazo-Pinto,J.F; Gil-Marín,J.A; Khan-Prado,L.;
Revista de la Facultad de Agronomía , 2007,
Abstract: this research was carried out at santa elena de las pi?as irrigation system, guarapiche river valley, maturin, venezuela, and its objective was to establish the effect of three irrigation frequencies (if) on the seed cotton yield and the boll and seed characters in four cotton cultivars (c). trial was sowed in a split-plot design with three replications, the if (6, 9 and 12 days) were assigned to the main plots and the four c (cabuyare, deltapine 16, deltapine 61 and acala 90-1) were assigned to the subplots. means were tested by duncan multiple range test. the statistical level used was 5%. irrigation was applied by siphons of 50.8 mm. current evapotranspiration (eta) was calculated by: eta = cd/hf, where cd = consumed depth and hf = number of days among samplings, while the crop coefficient (k) was calculated by: k = eta/etp, the etp was the mean of the methods proposed by thorhwhaite, garcia-lópez and blaney-criddle. two harvests were accomplished, the first one (fh) at 107 days after sowing (das) and the second one (sh) at 123 das. there were not significant differences for if, c and fr * c interaction for the following characters: lint yield.ha-1 (lyh) in the fh (365.2 kg.ha-1), seed yield.ha-1 (syh) in the fh (544.9 kg.ha-1), seed cotton yield.ha-1 (scyh) in the fh (911.5 kg.ha-1), scyh in the total production (1.565,3 kg.ha-1) and seed cotton percentage in the fh with relationship to total production (56.42%). for lyh, syh and scyh in the sh, the yielder c was deltapine 61 with 330.3; 497.5 and 824.0 kg.ha-1), respectively, outyield deltapine 16. the if did not affect significantly seed cotton yields. eta varied between 0.39 and 3.20 mm.day-1 for 6-day if; between 0.17 and 1.69 mm.day-1 for 9-day if and between 0.11 and 0.84 mm/day for 12-day if, while the k crop coefficient varied between 0.08 and 0.64 for 6-day if; between 0.03 and 0.36 for 9-day if and enter 0.02 and 0.18 for 12-day if. in conclusion, irrigation did not affect fiber, seed and seed cotton y
Efeito de cloreto de clorocolina e cloreto de mepiquat na cultura do algod?o (Gossypium hirsutum L.)
Cia, E.;Carvalho, L. H.;Kondo, J. I.;Fuzatto, M. G.;Bortoletto, N.;Gallo, P. B.;Cruz, L. S. P.;Sabino, N. P .;Pettinelli Jr., A.;Martins, A. L. M.;Silveira, J. C. O.;
Planta Daninha , 1984, DOI: 10.1590/S0100-83581984000200002
Abstract: a comparative study of the effects of chlrocoline chloride and mepiquat chloride growth regulators, on cotton (gossypium hirsutum l.) in regions of sao paulo state, during 1980/81 and 1981/82 was carried out. the treatments were: the basic of 50g/ha applied at 60-70 days after emergency; the same dose divided in 30g/h a at the same date and 20g/h a at 15 days after, and parceled application of 75g/h a, being 50g/h a at 60- 70 days and 25g/h a at 75-80 days afte r emergence. tests were analyzed in two groups, those with higher plant height and those, with smaller plants. yield, plant height, technologycal characters and yield distribution on the plant were evaluated. the last character consisting in the percentage of bolls set on the lower 35 cm plant height. the results showed a significative effect for yield in the case of the group of more developed plants. in this group the 30 + 20g/h a parceled dose showed the highest yield. for both groups the regulator reduced significan tly the height of the plants. they induced an increase in seed grade, boll weight, fiber length and decrease in percentage of fibers. there was also a higher concentration of bolls on the lower 35 cm of the treated plots.
Araneofauna (Arachnida: Araneae) en cultivos de algodón (Gossypium hirsutum) transgénicos y convencionales en el norte de Santa Fe, Argentina
Melina Soledad Almada,María Ana Sosa,Alda Gonzalez
Revista de Biología Tropical , 2012,
Abstract: Las ara as tienen un valor potencial considerable por su rol depredador de insectos, estas son plagas de la agricultura. Durante la campa a agrícola 2005/06, en INTA Reconquista, Santa Fe (Argentina) se estudio la composición de ara as presentes en cultivos de algodón transgénico y convencional, mediante un dise o experimental de bloques completos al azar, con tres repeticiones y tres tratamientos: algodón transgénico Bt (ALBt), algodón convencional sin control químico (ALCSC) y con control químico (ALCCC). Semanalmente, se capturaron ara as, con una red entomológica de arrastre, pa o vertical de 1m y trampas de caída. Asimismo se recolectaron 1 255 ejemplares (16 familias y 32 especies). Siete familias se presentaron en los tres tratamientos, donde predomino Thomisidae (n=1 051, 84.04%) y Araneidae (n=83, 6.64%). El gremio cazadoras por emboscada (n=1 053, 83.91%), “Tejedoras de telas orbiculares” (n=85, 6.77%) y “Cazadoras al acecho” (n=53, 4.22%) fueron las más abundantes. No hubo diferencias significativas en los índices de diversidad entre tratamientos. Las ara as se presentaron durante todo el ciclo del cultivo, con picos en las semanas de floración y madurez de las capsulas, además la mayor abundancia la encontramos en el ALBt. Este trabajo constituye el primer registro sobre la comunidad de ara as en cultivos de algodón para Argentina. Arachnofauna (Araneae: Araneae) in transgenic and conventional cotton crops (Gossypiumhirsutum) in the North of Santa Fe, Argentina. Spiders have considerable potential importance for their role as predators to some pests in agricultural systems. The composition of spiders in transgenic and conventional cotton at the Research Station of INTA Reconquista (Santa Fe) was studied during the 2005-2006 season. The experiment was a complete randomized block design with three replications and three treatments: transgenic Bt cotton (ALBt), conventional cotton without chemical control (ALCSC), and conventional cotton with chemical control (ALCCC). Weekly, spiders were collected using nets, vertical cloth and pitfall-traps. A total of 1 255 specimens (16 families, and 32 species) were collected. Seven families were found in all the treatments, mainly Thomisidae (n=1 051, 84.04%) and Araneidae (n=83, 6.64%). The Hunting spiders guild ambushers (n=1 053, 83.91%), “Orb weavers” (n=85, 6.77%) and “Stalkers” (n=53, 4.22%) were more abundant. There were no significant differences in the indexes diversity between treatments. Spiders were presented during the whole crop season, with peaks about flowering and boll maturity, with the
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.