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Bioecologia de Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae) em videira

Zart, Marcelo
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: iv, 73 f. : il.
Português
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV; A espécie de mosca-das-frutas Anastrepha fraterculus é uma das principais pragas da fruticultura brasileira, porém, quando associada à cultura da videira, poucas informações estão disponíveis. Neste trabalho foi avaliado o efeito da infestação artificial em diferentes cultivares e estádios fenológicos, a eficiência de atrativos alimentares para o monitoramento da praga e a flutuação populacional de adultos em diferentes cultivares na região da Serra Gaúcha, RS. No laboratório foi estudado o desenvolvimento pós-embrionário de A. fraterculus em diferentes cultivares. Não ocorre desenvolvimento de A. fraterculus na cultivar ‘Niagara Rosada’. Na cultivar ‘Itália’ a espécie completa o desenvolvimento, mas a cultivar não é considerada um hospedeiro multiplicador da praga devido a baixa viabilidade larval. No que se refere à caracterização de danos, houve queda significativa de bagas nas cultivares ‘Cabernet Sauvignon’, ‘Moscato Embrapa’ e ‘Isabel’ quando a infestação ocorreu na fase inicial de desenvolvimento do cacho (fase de grão ervilha). Na cultivar ‘Niagara Rosada’ não houve queda significativa e deformação das bagas e nem viabilidade no desenvolvimento larval. Atrativos alimentares foram testados em vinhedos e a formulação BioAnastrepha...

Plant enolase: gene structure, expression, and evolution.

Van der Straeten, D; Rodrigues-Pousada, R A; Goodman, H M; Van Montagu, M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1991 Português
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Enolase genes were cloned from tomato and Arabidopsis. Comparison of their primary structures with other enolases revealed a remarkable degree of conservation, except for the presence of an insertion of 5 amino acids unique to plant enolases. Expression of the enolase genes was studied under various conditions. Under normal growth conditions, steady-state messenger and enzyme activity levels were significantly higher in roots than in green tissue. Large inductions of mRNA, accompanied by a moderate increase in enzyme activity, were obtained by an artificial ripening treatment in tomato fruits. However, there was little effect of anaerobiosis on the abundance of enolase messenger. In heat shock conditions, no induction of enolase mRNA was observed. We also present evidence that, at least in Arabidopsis, the hypothesis that there exists a complete set of glycolytic enzymes in the chloroplast is not valid, and we propose instead the occurrence of a substrate shuttle in Arabidopsis chloroplasts for termination of the glycolytic cycle.

Temporal Stability and Biodiversity of Two Complex Antilisterial Cheese-Ripening Microbial Consortia

Maoz, Ariel; Mayr, Ralf; Scherer, Siegfried
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/2003 Português
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The temporal stability and diversity of bacterial species composition as well as the antilisterial potential of two different, complex, and undefined microbial consortia from red-smear soft cheeses were investigated. Samples were collected twice, at 6-month intervals, from each of two food producers, and a total of 400 bacterial isolates were identified by Fourier-transform infrared spectroscopy and 16S ribosomal DNA sequence analysis. Coryneform bacteria represented the majority of the isolates, with certain species being predominant. In addition, Marinolactobacillus psychrotolerans, Halomonas venusta, Halomonas variabilis, Halomonas sp. (106 to 107 CFU per g of smear), and an unknown, gram-positive bacterium (107 to 108 CFU per g of smear) are described for the first time in such a consortium. The species composition of one consortium was quite stable over 6 months, but the other consortium revealed less diversity of coryneform species as well as less stability. While the first consortium had a stable, extraordinarily high antilisterial potential in situ, the antilisterial activity of the second consortium was lower and decreased with time. The cause for the antilisterial activity of the two consortia remained unknown but is not due to the secretion of soluble...

Uronic Acid Products Release from Enzymically Active Cell Wall from Tomato Fruit and Its Dependency on Enzyme Quantity and Distribution 1

Huber, Donald J.; Lee, James H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1988 Português
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Isolated cell wall from tomato (Lycopersicon esculentum Mill. cv Rutgers) fruit released polymeric (degree of polymerization [DP] > 8), oligomeric, and monomeric uronic acids in a reaction mediated by bound polygalacturonase (PG) (EC 3.2.1.15). Wall autolytic capacity increased with ripening, reflecting increased levels of bound PG; however, characteristic oligomeric and monomeric products were recovered from all wall isolates exhibiting net pectin release. The capacity of wall from fruit at early ripening (breaker, turning) to generate oligomeric and monomeric uronic acids was attributed to the nonuniform ripening pattern of the tomato fruit and, consequently, a locally dense distribution of enzyme in wall originating from those fruit portions at more temporally advanced stages of ripening. Artificial autolytically active wall, prepared by permitting solubilized PG to bind to enzymically inactive wall from maturegreen fruit, released products which were similar in size characteristics to those recovered from active wall isolates. Extraction of wall-bound PG using high concentrations of NaCl (1.2 molar) did not attenuate subsequent autolytic activity but greatly suppressed the production of oligomeric and monomeric products. An examination of water-soluble uronic acids recovered from ripe pericarp tissue disclosed the presence of polymeric and monomeric uronic acids but only trace quantities of oligomers. The significance in autolytic reactions of enzyme quantity and distribution and their possible relevance to in vivo pectin degradation will be discussed.

Isolation, Characterization, and Cloning of α-l-Arabinofuranosidase Expressed during Fruit Ripening of Japanese Pear

Tateishi, Akira; Mori, Hitoshi; Watari, Junya; Nagashima, Kenji; Yamaki, Shohei; Inoue, Hiroaki
Fonte: American Society of Plant Biologists Publicador: American Society of Plant Biologists
Tipo: Artigo de Revista Científica
Publicado em /07/2005 Português
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α-l-Arabinofuranosidase (α-l-arafase) was purified from fruit of Japanese pear (Pyrus pyrifolia). The enzyme solubilized from the cell wall by NaCl and Triton X-100 had the homogeneity of a single 62-kD polypeptide on SDS-PAGE after purification through the steps of hydroxyapatite, anion-exchange chromatography, and size-exclusion chromatography. A related cDNA clone was isolated (PpARF2). The transcript and related protein were detected solely in the ripening fruit corresponding to the increase of α-l-arafase activity. Transcripts of PpARF2 were not detected in buds, leaves, roots, or shoots of the Japanese pear. The deduced amino acid sequences of PpARF2 had low identity with those of other plants or bacteria. This α-l-arafase belonged to glycoside hydrolase family 3, which includes some β-xylosidases. The purified enzyme hydrolyzed mainly p-nitrophenyl α-l-arabinofuranoside and also reacted bifunctionally with p-nitrophenyl β-d-xylopyranoside. However, it released only arabinose from native cell wall polysaccharides prepared from Japanese pear and from sugar beet arabinan. The enzyme did not release xylose from arabinoxylan and xylan. The only activity of the α-l-arafase presented here was hydrolyzing the arabinosyl residue from native polysaccharides...

Indirect Massage of the lens for the artificial ripening of Cataract

Jackson, Edward
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //1893 Português
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Cloning of the Papaya Chromoplast-Specific Lycopene β-Cyclase, CpCYC-b, Controlling Fruit Flesh Color Reveals Conserved Microsynteny and a Recombination Hot Spot1[W][OA]

Blas, Andrea L.; Ming, Ray; Liu, Zhiyong; Veatch, Olivia J.; Paull, Robert E.; Moore, Paul H.; Yu, Qingyi
Fonte: American Society of Plant Biologists Publicador: American Society of Plant Biologists
Tipo: Artigo de Revista Científica
Português
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Carotenoid pigments in fruits are indicative of the ripening process and potential nutritional value. Papaya (Carica papaya) fruit flesh color is caused by the accumulation of lycopene or β-carotenoids in chromoplasts. It is a distinct feature affecting nutritional composition, fruit quality, shelf life, and consumer preference. To uncover the molecular basis of papaya flesh color, we took map-based cloning and candidate gene approaches using integrated genetic and physical maps. A DNA marker tightly linked to flesh color colocalized on a contig of the physical map with a cDNA probe of the tomato (Solanum lycopersicum) chromoplast-specific lycopene β-cyclase, CYC-b. Candidate gene sequences were obtained from amplified fragments and verified by sequencing two bacterial artificial chromosomes containing the two alleles. Sequence comparison revealed a 2-bp insertion in the coding region of the recessive red flesh allele resulting in a frame-shift mutation and a premature stop codon. A color complementation test in bacteria confirmed that the papaya CpCYC-b is the gene controlling fruit flesh color. Sequence analysis of wild and cultivated papaya accessions showed the presence of this frame-shift mutation in all red flesh accessions examined. Evaluation of DNA markers near CpCYC-b revealed a recombination hot spot...

Genetic Control of a Transition from Black to Straw-White Seed Hull in Rice Domestication1[C][W][OA]

Zhu, Bo-Feng; Si, Lizhen; Wang, Zixuan; Jingjie Zhu, Yan Zhou; Shangguan, Yingying; Lu, Danfeng; Fan, Danlin; Li, Canyang; Lin, Hongxuan; Qian, Qian; Sang, Tao; Zhou, Bo; Minobe, Yuzo; Han, Bin
Fonte: American Society of Plant Biologists Publicador: American Society of Plant Biologists
Tipo: Artigo de Revista Científica
Português
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The genetic mechanism involved in a transition from the black-colored seed hull of the ancestral wild rice (Oryza rufipogon and Oryza nivara) to the straw-white seed hull of cultivated rice (Oryza sativa) during grain ripening remains unknown. We report that the black hull of O. rufipogon was controlled by the Black hull4 (Bh4) gene, which was fine-mapped to an 8.8-kb region on rice chromosome 4 using a cross between O. rufipogon W1943 (black hull) and O. sativa indica cv Guangluai 4 (straw-white hull). Bh4 encodes an amino acid transporter. A 22-bp deletion within exon 3 of the bh4 variant disrupted the Bh4 function, leading to the straw-white hull in cultivated rice. Transgenic study indicated that Bh4 could restore the black pigment on hulls in cv Guangluai 4 and Kasalath. Bh4 sequence alignment of all taxa with the outgroup Oryza barthii showed that the wild rice maintained comparable levels of nucleotide diversity that were about 70 times higher than those in the cultivated rice. The results from the maximum likelihood Hudson-Kreitman-Aguade test suggested that the significant reduction in nucleotide diversity in rice cultivars could be caused by artificial selection. We propose that the straw-white hull was selected as an important visual phenotype of nonshattered grains during rice domestication.

Hyperspectral and Chlorophyll Fluorescence Imaging to Analyse the Impact of Fusarium culmorum on the Photosynthetic Integrity of Infected Wheat Ears

Bauriegel, Elke; Giebel, Antje; Herppich, Werner B.
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 28/03/2011 Português
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Head blight on wheat, caused by Fusarium spp., is a serious problem for both farmers and food production due to the concomitant production of highly toxic mycotoxins in infected cereals. For selective mycotoxin analyses, information about the on-field status of infestation would be helpful. Early symptom detection directly on ears, together with the corresponding geographic position, would be important for selective harvesting. Hence, the capabilities of various digital imaging methods to detect head blight disease on winter wheat were tested. Time series of images of healthy and artificially Fusarium-infected ears were recorded with a laboratory hyperspectral imaging system (wavelength range: 400 nm to 1,000 nm). Disease-specific spectral signatures were evaluated with an imaging software. Applying the ‘Spectral Angle Mapper’ method, healthy and infected ear tissue could be clearly classified. Simultaneously, chlorophyll fluorescence imaging of healthy and infected ears, and visual rating of the severity of disease was performed. Between six and eleven days after artificial inoculation, photosynthetic efficiency of infected compared to healthy ears decreased. The severity of disease highly correlated with photosynthetic efficiency. Above an infection limit of 5% severity of disease...

Studies on physico-chemical changes during artificial ripening of banana (Musa sp) variety ‘Robusta’

Kulkarni, Shyamrao Gururao; Kudachikar, V. B.; Keshava Prakash, M. N.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
Português
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Banana (Musa sp var ‘Robusta’) fruits harvested at 75–80% maturity were dip treated with different concentrations of ethrel (250–1,000 ppm) solution for 5 min. Ethrel at 500 ppm induced uniform ripening without impairing taste and flavour of banana. Untreated control banana fruits remained shriveled, green and failed to ripen evenly even after 8 days of storage. Fruits treated with 500 ppm of ethrel ripened well in 6 days at 20 ± 1 °C. Changes in total soluble solids, acidity, total sugars and total carotenoids showed increasing trends up to 6 days during ripening whereas fruit shear force values, pulp pH and total chlorophyll in peel showed decreasing trends. Sensory quality of ethrel treated banana fruits (fully ripe) were excellent with respect to external colour, taste, flavour and overall quality.

Fingerprinting of hydroxyl radical-attacked polysaccharides by N-isopropyl-2-aminoacridone labelling

Vreeburg, Robert A. M.; Airianah, Othman B.; Fry, Stephen C.
Fonte: Portland Press Ltd. Publicador: Portland Press Ltd.
Tipo: Artigo de Revista Científica
Português
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16.89873%
Hydroxyl radicals (•OH) cause non-enzymic scission of polysaccharides in diverse biological systems. Such reactions can be detrimental (e.g. causing rheumatic and arthritic diseases in mammals) or beneficial (e.g. promoting the softening of ripening fruit, and biomass saccharification). Here we present a method for documenting •OH action, based on fluorescent labelling of the oxo groups that are introduced as glycosulose residues when •OH attacks polysaccharides. The method was tested on several polysaccharides, especially pectin, after treatment with Fenton reagents. 2-Aminoacridone plus cyanoborohydride reductively aminated the oxo groups in treated polysaccharides; the product was then reacted with acetone plus cyanoborohydride, forming a stable tertiary amine with the carbohydrate linked to N-isopropyl-2-aminoacridone (pAMAC). Digestion of labelled pectin with ‘Driselase’ yielded several fluorescent products which on electrophoresis and HPLC provided a useful ‘fingerprint’ indicating •OH attack. The most diagnostic product was a disaccharide conjugate of the type pAMAC·UA-GalA (UA=unspecified uronic acid), whose UA-GalA bond was Driselase-resistant (product 2A). 2A was clearly distinguishable from GalA-GalA–pAMAC (disaccharide labelled at its reducing end)...

Fenologia, Produção e Pós-colheita de frutos de buriti (Mauritia flexuosa L.f) em três veredas do cerrado no estado de Goiás.; Phenologu, Production and post-harvest e fruit buriti (Mauritia flexuosa L.f) into three palm swamp of the savanna in Goias state.

MARTINS, Maria Lúcia
Fonte: Universidade Federal de Goiás; BR; UFG; Doutorado em Agronomia; Ciências Agrárias Publicador: Universidade Federal de Goiás; BR; UFG; Doutorado em Agronomia; Ciências Agrárias
Tipo: Dissertação Formato: application/pdf
Português
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This study aimed to characterize the phenology, production and post-harvest fruit of the buriti palm tree in the Savannah as well as factors impacting on production. The study was conducted in three palm swamp with three distinct forms of occupation of the borders. The buriti palm tree were characterized as height, diameter at breast height, number of inflorescences and leaves. The number of leaves was correlated with climatic data from July 2006 to September 2009. To characterize the production were collected from three clusters per area, and determined the average weight of fruit bunches and these extrapolated data for each area. In three clusters of each palm swamp included: length of the bunch, bunch weight, fruit weight, number of rachilles, and fruit number, length rachilles, total number of loci, number of loci with fruit, no fruit locule number , and the reason the number of loci with fruits / total number of loci. Characterization were carried out fifty fruits of each of the three clusters collected in each area. The characterization of fruits were evaluated: fruit weight, diameter longitudinal, transverse diameter, transverse diameter ratio / longitudinal diameter, the pulp mass, mass of bark, seed mass, and mass of endocarp. The pulp included: pH...

Exclusion of sunlight from Shiraz grapes alters wine colour tannin and sensory properties

Ristic, R.; Downey, M.; Iland, P.; Bindon, K.; Francis, I.; Herderich, M.; Robinson, S.
Fonte: Australian Society of Viticulture and Oenology Publicador: Australian Society of Viticulture and Oenology
Tipo: Artigo de Revista Científica
Publicado em //2007 Português
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The aim of this study was to determine how changes in grape composition brought about by artificial shading (sunlight exclusion) influence wine properties including colour, flavonoid composition and sensory attributes. Prior to flowering, bunches of Shiraz grapes were enclosed in boxes designed to eliminate light without altering bunch temperature and humidity. This artificial bunch shading had little effect on berry ripening and accumulation of sugar but at harvest the shaded bunches had smaller berries and higher seed weight, juice pH and titratable acidity. The amount of anthocyanins in the fruit was not changed significantly but anthocyanin composition in the shaded berries was shifted towards dioxygenated anthocyanins (the glucosides of cyanidin and peonidin derivatives). Shaded fruit had increased seed tannins and decreased skin tannins but the largest relative change in flavonoids was a marked decrease in flavonols in the shaded fruit, similar to previous studies. Wines made from shaded fruit had lower wine colour density, total phenolics, anthocyanins and tannins when the wine was bottled and after ageing for up to three years. Analysis of potential flavour compounds following acid hydrolysis indicated that the wines made from shaded fruit had decreased levels of glycosides of β-damascenone and 1...