Effect of water stress on herbicide efficiency applied to Urochloa decumbens

M.R. Rocha-Pereira, A.E. Klar, D. Martins, G.S. Ferreira de Souza, and J. Villalba. 2012. Effect of water stress on herbicide efficiency applied to Urochloa decumbens. Cien. Inv. Agr. 39(1): 211-220. This project aimed to measure the control efficiency of Acctil Coenzime A Carboxilase (ACCase)-inhibiting herbicides post-emergence applied to Urochloa decumbens (Stapf) R.D. Webster under different soil water contents. The experiment was conducted in a greenhouse at the Department of Plant Production, Faculty of Agronomic Sciences, UNESP, Botucatu, Silo Paulo. The experimental design was a completely randomized design with four replications, consisting of a 9 x 4 factorial, combined with three water management systems (-0.03, -0.07 and -1.5 MPa) and three herbicides (fluazifop-p-butyl, haloxyfop-methyl and sethoxydim + oil using four doses (100, 50, 25 and 0% of the recommended dose). Herbicide applications were conducted at two vegetative stages for all species: a 4-6 leaf stage and a 2-3 tiller stage. The physiological parameters evaluated were as follows: photosynthetic rate, stomatal conductance, transpiration, leaf temperature and plant dry matter. The visual assessments of phytotoxicity were performed 28 days after herbicide application. The control efficiency was lower in plants grown under soil water potential conditions of -1.5 MPa, regardless of the herbicide used during the two application stages; however, none reached 100% control. Fractionation of the recommended herbicide doses reduced effectiveness, with the exception of the 50%-dose application of sethoxydim and fluazifop-p-butyl herbicides, which were also effective in the 4-6 leaf plant control under normal water conditions.

Influência do estresse nutricional programado na composição da microalga isochrysis galbana

Global warming due to Greenhouse Gases (GHG) emissions, especially CO2, has been identified as one of the major problems of the twenty-first century, considering the consequences that could represent to planet. Currently, biological processes have been mentioned as a possible solution, especially CO2 biofixation due to association microalgae growth. This strategy has been emphasized as in addition to CO2 mitigation, occurs the production of biomass rich in compounds of high added value. The Microalgae show high photosynthetic capacity and growth rate higher than the superior plants, doubling its biomass in one day. Its culture does not show seasons, they grow in salt water and do not require irrigation, herbicides or pesticides. The lipid content of these microorganisms, depending on the species, may range from 10 to 70% of its dry weight, reaching 90% under certain culture conditions. Studies indicate that the most effective method to promote increased production of lipids in microalgae is to induce stress by limiting nitrogen content in the culture medium. These evidences justify research continuing the production of biofuels from microalgae. In this paper, it was studied the strategy of increasing the production of lipids in microalgae I. galbana with programmed nutritional stress, due to nitrogen limitation. The physiological responses of microalgae, grown in f / 2 with different concentrations of nitrogen (N: P 15,0-control, N: 5,0 P and N: P 2,5) were monitored. During exponential phase, results showed invariability in the studied conditions. However the cultures subjected to stress in stationary phase, showed lower biomass yields. There was an increase of 32,5% in carbohydrate content and 87.68% in lipids content at N: P ratio of 5,0 and an average decrease of 65% in protein content at N: P ratios of 5, 0 and 2.5. There were no significant variations in ash content, independently of cultivation and growth phase. Despite the limitation of biomass production in cultures with N: P smaller ratios, the increase of lipid accumulation highest lipids yields were observed as compared to the control culture. Given the increased concentration of lipids associated to stress, this study suggests the use of microalgae Isochrysis galbana as an alternative raw material for biofuel production

Análises físico-químicas de polpas de frutas e avaliação dos seus padrões de identidade e qualidade

The pulps are products that add economic value enjoy the fruits of the surplus productions of the same. Have good market acceptance because of its practicality and diversity of flavors available year round. In order to assess the quality of the fruit pulp through the physical and chemical parameters and the characteristics of manufacturing industry, we analyzed 36 samples of frozen fruit pulp of three brands marketed in RIO Grande do Norte, 14 brand A, 12 of 10 brand B and brand C, which corresponded to 14 different flavors, of which 10 have identity Standards and Quality (ISQ S) established by the Ministério da Agricultura, Pecuária e Abastecimento (MAPA), totaling 27 samples with ISQ s. We conducted the following physicalchemical analyzes on samples of fruit pulp: Total solids, total soluble solids, pH, titratable acidity, total sugars and the determination of ascorbic acid. The percentage of failure for each parameter evaluated was 37, 04% in total soluble solids, 22,22% for total solids and titratable acidity, 7,40% in relation to pH. The total sugars were within the requirements demanded by the MAPA and ascorbic acid content, determined only in the pulp of acerola and cashew, presented a non compliance in the pulp of brand B. The percentage of failures of the pulps with ISQ S was 59% with brand A, B and C accounted for 3,70%, 33,33% and 22,22% respectively. The pulps which have no established atandards such as pineapple pulp, showed similar values between brands and literature data unlike the pulp of plum, jackfruit and tamarind which diverged greatly in parameters such as total solids and total soluble solids. The study demonstrates the need for greater quality control by the producers with respect to raw materials, processing, packing, stored and the importance of ISQ S to establish the flavors have not yet covered by existing legislation, but already highly commercialized

Genetic diversity in Egeria densa and E. najas in Jupia Reservoir, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vitro anti-Mycobacterium tuberculosis activity of some Brazilian Cerrado plants

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Infestación natural de Lonchaeidae (Diptera) en variedades de melocotón

Se estudió la ocurrencia de Lonchaeidae en variedades de melocotón, conducidos sobre los patrones ‘Okinawa’ y Umê: Tropical, Ouromel 3, Jóia 4, Régis, Talismã, Aurora 2, Aurora 1, Dourado 2 y Doçura 2. Se colectaron muestras de 30 frutos por planta en el Banco de Germoplasma en Presidente Prudente, Brasil. Se obtuvieron 633 especímenes de Lonchaeidae; 394 de ellos en frutos de variedades sobre ‘Okinawa’ y 239 sobre Umê. Se capturaron especies como Neosilba zadolicha, N. inesperata, N. pendula, N. certa y Neosilba spp. (hembras). N. zadolicha y N. inesperata, se observaron en 77,78% de las muestras de las variedades sobre ‘Okinawa’. Sobre el patrón Umê la mayor incidencia fue de N. zadolicha , N. inesperata y N. pendula (55,6%, 33,3% y 33,3% respectivamente). Las variedades Ouromel 3, Talismã, Doçura 2 y Aurora 2 presentaron mayores infestaciones por Lonchaeidae. N. certa tuvo una menor incidencia y sólo se observó en la variedad Doçura 2 sobre ‘Okinawa’. Plantas con mayor número de frutos presentaron mayor incidencia de moscas por fruto; sin embargo, no hubo correlación entre peso del fruto y número de moscas. No se observó diferencia para peso del fruto y número de moscas por fruto entre los dos patrones, ‘Okinawa’ y Umê. Melocotones crecidos en los patrones ‘Okinawa’ y Umê en Presidente Prudente están infestados por especies de Lonchaeidae que presentan preferencia independientemente del peso de los frutos. El aporte de este trabajo al conocimiento de la comunidad de especies de Lonchaeidae ofrece una base para su control.

Los instrumentos económicos en la gestión del agua: el caso de Costa Rica

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Estrategias empresariales en la transformación industrial argentina

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La regulación económica como complemento de las licitaciones en las concesiones de obras públicas

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Estructuralismo latinoamericano y teoría económica

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Ciclo reprodutivo e análise ultraestrutural da espermatogênese de Cichla kelberi (TeLeostei: Perciformes: Cichlidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização da mobilização das reservas das sementes do maracujá-amarelo (Passiflora edulis Sims f. flavicarpa O. Deg) durante a germinação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização do óleo de frutos de tucumã (Astrocaryum aculeatum) para produção de biodiesel

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Exposición del Sr. Carlos Martínez Sotomayor, Director Regional del UNICEF para las Américas, en la ceremonia inaugural del Simposio

Inauguración oficial del Director Regional del UNICEF del Simposio en el cual alude al objetivo de éste, que es definir qué es el desarrollo social, cuáles son sus fines y sus relaciones con lo económico y con los regímenes políticos y, sobre todo, cuáles son sus medios para aumetnar el bienestar humano.

A extração e a indústria da madeira no município de Rio Branco - AC

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)