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Search Results: 1 - 10 of 193811 matches for " Oliveira Jurandi Gon?alves de "
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Marcadores moleculares RAPD e descritores morfológicos na avalia o da diversidade genética de goiabeiras (Psidium guajava L.) = RAPD molecular markers and morphological descriptors in the evaluation of genetic diversity of guava (Psidium guajava L.)
Aroldo Gomes Filho,Jurandi Gonalves de Oliveira,Alexandre Pio Viana,Ana Paula de Oliveira Siqueira
Acta Scientiarum : Agronomy , 2010,
Abstract: O conhecimento da variabilidade genética e fenotípica entre diferentes acessos de goiabeiras é importante para se apoiar programas de melhoramento dessa espécie na regi o Norte Fluminense que carece de novas culturas capazes de gerar renda aos produtores locais. O objetivo deste trabalho foi avaliar a divergência genética entre seis cultivares e 19 acessos de goiabeiras, por meio de marcadores moleculares RAPD e características morfoagron micas. Foram obtidas 117 marcas polimórficas, utilizando-se 28 iniciadores. Os resultados mostraram uma concordancia parcial entre os métodos de agrupamentos estudados, com a forma o de 12 grupos. O acesso Vita 3 e o acesso 6 foram os mais divergentes, apresentando distancia genética de 0,663. A análise comparativa dos agrupamentos revelou que os marcadores RAPD e os descritores morfológicos foram eficientes para discrimina o dos acessos e que houve variabilidade genética potencial para uso em Programa de Melhoramento Genético. The knowledge of the genetic and phenotypic variability among different accessions of guava is important for supporting improvement programs of this specie in northern Rio de Janeiro state, which needs new cultivars able to generate income for local farmers. This work aimed to evaluate the genetic divergence among six cultivars and 19 accessions of guava via RAPD molecular markers and morphologicalcharacteristics. One hundred and seventeen polymorphic markers were obtained from 28 primers. The results showed a partial agreement between the methods of studied groupings, with the formation of 12 groups. The accessions ‘Vita 3’and ‘6’ were the most divergent, showing genetic distance of 0.663. The comparative analysis of groupings showed that RAPD markers and morphological descriptors were effective in discriminating the accessions and to show potentialgenetic variability useful in genetic improvement programs.
The effect of chilling on the photosynthetic activity in coffee (Coffea arabica L.) seedlings: The protective action of chloroplastid pigments
Oliveira, Jurandi Gonalves de;Alves, Pedro Luis C.A.;Magalh?es, Antonio Celso;
Brazilian Journal of Plant Physiology , 2002, DOI: 10.1590/S1677-04202002000200003
Abstract: coffea arabica is considered to be sensitive to low temperatures, being affected throughout its entire life cycle. injury caused by chilling (low temperatures above zero degree centigrade) is characterized primarily by inhibition of the photosynthetic process. the objective of this work was to evaluate the role of photosynthetic pigments in the tolerance of coffee (c. arabica l.) seedlings to chilling. the evaluation the photosynthetic activity was made by emission of chl a fluorescence at room temperature (25 oc) in vivo and in situ, using a portable fluorometer. the pigment content was obtained by extraction with 80 % acetone, while estimation of membrane lipid peroxidation was determined by measuring the mda content in leaf tissue extracts. the results indicated a generalized reduction in the quantum yield of psii when the seedlings were maintained in the dark. the reduction occurred in the seedlings submitted to chilling treatment as well as in the control ones. this demonstrates that not only chilling acts to cause an alteration in psii. it is possible that the tissue storage reserves had been totally exhausted, with the respiratory rate exceeding the photosynthetic rate; the later was nil, since the seedlings were kept in the dark. the efficiency in the capture, transfer and utilization of light energy in psii photochemical reactions requires a sequence of photochemical, biochemical and biophysical events which depend on the structural integrity of the photosynthetic apparatus. however, this efficiency was found to be related to the protective action of chloroplastid pigments, rather than to the concentration of these pigments.
The effect of chilling on the photosynthetic activity in coffee (Coffea arabica L.) seedlings: The protective action of chloroplastid pigments
Oliveira Jurandi Gonalves de,Alves Pedro Luis C.A.,Magalh?es Antonio Celso
Brazilian Journal of Plant Physiology , 2002,
Abstract: Coffea arabica is considered to be sensitive to low temperatures, being affected throughout its entire life cycle. Injury caused by chilling (low temperatures above zero degree centigrade) is characterized primarily by inhibition of the photosynthetic process. The objective of this work was to evaluate the role of photosynthetic pigments in the tolerance of coffee (C. arabica L.) seedlings to chilling. The evaluation the photosynthetic activity was made by emission of Chl a fluorescence at room temperature (25 masculineC) in vivo and in situ, using a portable fluorometer. The pigment content was obtained by extraction with 80 % acetone, while estimation of membrane lipid peroxidation was determined by measuring the MDA content in leaf tissue extracts. The results indicated a generalized reduction in the quantum yield of PSII when the seedlings were maintained in the dark. The reduction occurred in the seedlings submitted to chilling treatment as well as in the control ones. This demonstrates that not only chilling acts to cause an alteration in PSII. It is possible that the tissue storage reserves had been totally exhausted, with the respiratory rate exceeding the photosynthetic rate; the later was nil, since the seedlings were kept in the dark. The efficiency in the capture, transfer and utilization of light energy in PS II photochemical reactions requires a sequence of photochemical, biochemical and biophysical events which depend on the structural integrity of the photosynthetic apparatus. However, this efficiency was found to be related to the protective action of chloroplastid pigments, rather than to the concentration of these pigments.
Portable chlorophyll meter for the quantification of photosynthetic pigments, nitrogen and the possible use for assessment of the photochemical process in Carica papaya L.
Torres Netto, Alena;Campostrini, Eliemar;Oliveira, Jurandi Gonalves de;Yamanishi, Osvaldo Kiyoshi;
Brazilian Journal of Plant Physiology , 2002, DOI: 10.1590/S1677-04202002000300004
Abstract: the techniques utilized to extract chlorophyll from plant materials are destructive and based on methods that use organic solvents. this study proposes the non-destructive quantification of chlorophyll and nitrogen concentration using a portable chlorophyll meter (spad-502). further, was possible to establish relationships between chlorophyll fluorescence and spad-502 values. this methodology could save time, space and resources, and could be used for analysis of the photosynthetic processes. papaya leaves (solo and formosa groups) of different ages were collected from 15-month-old plants cultivated in a commercial field in s?o francisco de itabapoana, rio de janeiro state (410:15w; 210:27s). correlations were established between the chlorophyll content and carotenoids extracted in dmso, nitrogen content, a chlorophyll a fluorescence (ff, fmax, fn/fmax, qn, qp, npq) with readings from spad-502 taken on papaya leaves of different ages. the results show that while the qp and the fn/fmax increased with spad-502 readings of up to 40, the qn and npq variables decreased. the fmax presented a direct linear correlation with the spad-502 values while the ff variable did not correlate with the spad-502 values. the portable chlorophyll meter was shown to be useful for nondestructive determination of photosynthetic pigments (chlorophyll and carotenoids) and can be used indirectly in advanced interpretation of the photochemical process in carica papaya l. leaves.
Photochemical efficiency in bean plants (Phaseolus vulgaris L. and Vigna unguiculata L. Walp) during recovery from high temperature stress
Costa, Ernany Santos;Bressan-Smith, Ricardo;Oliveira, Jurandi Gonalves de;Campostrini, Eliemar;Pimentel, Carlos;
Brazilian Journal of Plant Physiology , 2002, DOI: 10.1590/S1677-04202002000200004
Abstract: bean (phaseolus vulgaris l., cv. carioca and cv. negro huasteco) and cowpea plants (vigna unguiculata l. walp cv. epace 10) were grown in a growth chamber with ppf at leaf level of 200 mmol.m-2.s-1 and air temperature 25 + 1 oc. the first fully expanded pair of leaves of 12-day-old plants was submitted to high temperature stress (25, 30, 35, 40, 45 and 48 oc) for 1.5 h. the photochemical efficiency of psii during recovery was monitored by means of chlorophyll a fluorescence at six different times (0.5, 1, 2, 4, 24, and 48 h) after stress, at 25 oc, using a modulated fluorimeter. increasing temperature promoted an increase in ff at 45 oc, possibly associated with dissociation of the light harvesting complex from the reaction centre of psii, but a decrease was observed at 48 oc in all cultivars. fmax decreased at 48 oc in carioca and negro huasteco, but not in epace 10, showing a possible correlation between heat tolerance and fmax for this cultivar. the low values of fmax in carioca and negro huasteco indicated a loss of psii activity followed by death of these plants. fv/fmax did not vary in epace 10 but varied in carioca and negro huasteco with increasing temperatures.
Laminas de irriga??o e coberturas do solo sobre a incidência da mancha fisiológica e produtividade do mam?o "Golden"
Gomes Filho, Aroldo;Oliveira, Jurandi Gonalves de;Viana, Alexandre Pio;Pereira, Messias Gonzaga;
Ciência Rural , 2007, DOI: 10.1590/S0103-84782007000600023
Abstract: in this experiment the effect of different irrigation rates and soil coverings on qualitative aspects as well as yield components of the papaya cv. ?golden? during the period december 2003 to november 2004 were evaluated. a randomized complete block design was used with three replications in a factorial scheme. the results demonstrate high correlation involving the factors harvest season, incidence of skin freckles and yield components. with relation to skin freckles a seasonal incidence was confirmed, showing that for cv. ?golden?, the major incidence of the disturbance was verified in september. the mulching treatment was promising for the factors studied, in contrast to the green covering using the leguminosae arachis pintoe, due to competition with the papaya trees for water and nutrients, causing a reduction in the yield components.
Mancha fisiologica e produtividade do mam?o Tainung 01: efeito da lamina de irriga??o e cobertura do solo
Gomes Filho, Aroldo;Oliveira, Jurandi Gonalves de;Viana, Alexandre Pio;Pereira, Messias Gonzaga;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000400019
Abstract: in this experiment one evaluated the effect of different irrigation dosages and soil coverings in skin freckles aspects in yield components of the papaya cv. tainung 01 in the period from december 2003 to november 2004. it was used a randomized complete block design, with a three replications, in a factorial scheme. when the interactions were significant the analysis was partitioned and the means were compared by the tukey test for each factor. the results found demonstrated high correlation between the variable studied and the harvest season. with relation to the skin freckles the seasonal aspect of incidence was confirmed, showing that for cv. tainung 01 the major incidence of the disturbance was verified in september and october. with relation to the soil coverings, the mulching showed promising for the variables in yield, in contrast of the green covering with the leguminosae arachis pintoi, because the last one competed with the papaya trees causing reduction in the yield components.
Mancha fisiológica do mam?o: uma perspectiva de obten??o de material genético tolerante
Oliveira, Jurandi Gonalves de;Pereira, Messias Gonzaga;Martelleto, Luiz Aurélio Peres;Ide, Carlos David;
Revista Brasileira de Fruticultura , 2005, DOI: 10.1590/S0100-29452005000300028
Abstract: the occurrence of the physiological disturbance known as "skin freckle on papaya" (mfm) has reduced the quality of papaya (c. papaya l.) cultivated in brazil. the acquisition of genetic material tolerant to mfm is a very good strategy to overcome or at least to decrease the negative effects of such disturbance. in this present work, 22 papaya genotypes were evaluated in relation to the mfm, in the northern region of rio de janeiro state. the fruits were collected from a field testing installed in an experimental station of pesagro-rio, in the municipality of macaé. the experiment consisted of a randomized complete block design with four replications, with eight individual plants per plot. the data were submitted to the analysis of variance and to the mean comparison test. firstly it was conducted a combined analysis involving the two ripening stages - green-mature and ? mature. as the genotype by ripening stage was significant, each individual ripening stage was analyzed. based on the anova, the genotypic determination index (h2) for the trait mfm was estimated, which demonstrated that the evaluation on the second stage (? mature) shows higher value (67.85%) than in the green-mature stage (28.95%). thus, in such stage there is a better differentiation among genotypes. based on such results, it may be stated that there is expressive genetic variability among the evaluated genotypes, for this trait. so, there is a positive perspective of obtaining better genotypes - hybrids and varieties - in terms of tolerance to mfm via breeding programs. considering the strategy of breeding procedures, associated to adjustment of cultural practices, it represents new possibilities of growing papaya without the limitations caused by the mfm.
Photochemical efficiency in bean plants (Phaseolus vulgaris L. and Vigna unguiculata L. Walp) during recovery from high temperature stress
Costa Ernany Santos,Bressan-Smith Ricardo,Oliveira Jurandi Gonalves de,Campostrini Eliemar
Brazilian Journal of Plant Physiology , 2002,
Abstract: Bean (Phaseolus vulgaris L., cv. Carioca and cv. Negro Huasteco) and cowpea plants (Vigna unguiculata L. Walp cv. Epace 10) were grown in a growth chamber with PPF at leaf level of 200 mumol.m-2.s-1 and air temperature 25 + 1 oC. The first fully expanded pair of leaves of 12-day-old plants was submitted to high temperature stress (25, 30, 35, 40, 45 and 48 oC) for 1.5 h. The photochemical efficiency of PSII during recovery was monitored by means of chlorophyll a fluorescence at six different times (0.5, 1, 2, 4, 24, and 48 h) after stress, at 25 oC, using a modulated fluorimeter. Increasing temperature promoted an increase in Fphi at 45 oC, possibly associated with dissociation of the light harvesting complex from the reaction centre of PSII, but a decrease was observed at 48 oC in all cultivars. Fmax decreased at 48 oC in Carioca and Negro Huasteco, but not in Epace 10, showing a possible correlation between heat tolerance and Fmax for this cultivar. The low values of Fmax in Carioca and Negro Huasteco indicated a loss of PSII activity followed by death of these plants. Fv/Fmax did not vary in Epace 10 but varied in Carioca and Negro Huasteco with increasing temperatures.
Portable chlorophyll meter for the quantification of photosynthetic pigments, nitrogen and the possible use for assessment of the photochemical process in Carica papaya L.
Torres Netto Alena,Campostrini Eliemar,Oliveira Jurandi Gonalves de,Yamanishi Osvaldo Kiyoshi
Brazilian Journal of Plant Physiology , 2002,
Abstract: The techniques utilized to extract chlorophyll from plant materials are destructive and based on methods that use organic solvents. This study proposes the non-destructive quantification of chlorophyll and nitrogen concentration using a portable chlorophyll meter (SPAD-502). Further, was possible to establish relationships between chlorophyll fluorescence and SPAD-502 values. This methodology could save time, space and resources, and could be used for analysis of the photosynthetic processes. Papaya leaves (Solo and Formosa groups) of different ages were collected from 15-month-old plants cultivated in a commercial field in S o Francisco de Itabapoana, Rio de Janeiro State (41(0):15W; 21(0):27S). Correlations were established between the chlorophyll content and carotenoids extracted in DMSO, nitrogen content, a chlorophyll a fluorescence (Fphi, Fmax, Fnu/Fmax, qN, qP, NPQ) with readings from SPAD-502 taken on papaya leaves of different ages. The results show that while the q p and the Fnu/Fmax increased with SPAD-502 readings of up to 40, the qN and NPQ variables decreased. The Fmax presented a direct linear correlation with the SPAD-502 values while the Fphi variable did not correlate with the SPAD-502 values. The portable chlorophyll meter was shown to be useful for nondestructive determination of photosynthetic pigments (chlorophyll and carotenoids) and can be used indirectly in advanced interpretation of the photochemical process in Carica papaya L. leaves.
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