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Morfologia de embri es nucelares de laranja 'Valência' (Citrus sinensis (L.) Osbeck)  [cached]
Mendes-da-Glória Fernanda Januzzi,Mour?o Filho Francisco de Assis Alves,Appezzato-da-Glória Beatriz
Acta Botanica Brasilica , 2001,
Abstract: Esse trabalho teve como objetivo avaliar a morfologia de embri es nucelares de laranja 'Valência' (Citrus sinensis (L.) Osbeck) a fim de fornecer informa es para estudos de embriogênese somática induzida in vitro visando o melhoramento de citros que utilizem essa variedade. Para a realiza o dessas avalia es, embri es coletados de sementes provenientes de frutos maduros (13 meses após o florescimento) foram fixados, desidratados e preparados para a realiza o dos cortes histológicos seriados. Dos embri es avaliados, apenas um apresentou a morfologia de embri o zigótico. Os demais mostraram cotilédones com angula es e formatos distintos. Foram observados embri es mal formados com a n o diferencia o de ápice caulinar e/ou ápice radicular, n o desenvolvimento de um dos cotilédones, além de eixo embrionário colapsado. Os dados obtidos poder o auxiliar na interpreta o dos tipos morfológicos de embri es somáticos obtidos in vitro e sua capacidade de convers o em plantas.
Efeito de diferentes porta-enxertos no vigor e produtividade da laranjeira 'pera' (Citrus sinensis L.) Osbeck)
Mour?o Filho, Francisco de Assis Alves;Mischan, Martha Maria;Salibe, Ary Apparecido;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1991, DOI: 10.1590/S0071-12761991000100010
Abstract: the present study was carried out aiming to determine the effect of different rootstocks in plant vigor and yield of 'pera' sweet orange, citrus sinensis, (l.) osbeck. the research work was conducted in plants of a rootstock experiment, established at lageado experimental farm, unesp, botucatu, state of s?o paulo. the eight rootstocks studied were: 'rangpur' lime (citrus limonia, (l.) osbeck); 'volkamer' lemon (citrus volkameriana, pasquale); 'florida rough' lemon (citrus jambhiri, lushington); 'cleopatra' mandarin (citrus reshni, hort. ex. tanaka); 'sunki' mandarin (citrus sunki, hort. ex. tanaka); 'caipira' sweet orange (citrus sinesis (l.) osbeck); 'trifoliata' orange (poncirus trifoliata, rasfinesque) and 'carrizo' citrange (citrus sinensis x poncirus trifoliata) . the results showed that 'cleopatra' and 'sunki' mandarins and 'florida' rough lemon induced the greatest plant vigor. the rootstocks 'volkamer' lemon, 'florida' rough lemon, 'rangpur' lime and 'sunki' and 'cleopatra' mandarins induced the greatest total yields. the greatest values of eficiency index (yield (kg)/m3 canopy volume) were obtained in plants budded on 'trifoliata' orange, 'carrizo' citrange and 'rangpur' lime. characteristics of these rootstocks are discussed.
época da indu o e evoca o floral em Citrus sinensis (L.) Osbeck cv. Pêra Rio  [cached]
Pereira Iara Alvarenga Mesquita,Pinto José Eduardo Brasil Pereira,Davide Lisete Chamma
Ciência Rural , 2003,
Abstract: A produ o do estímulo floral (indu o) e emiss o das primeiras sépalas, na gema floralmente determinada (evoca o floral) em Citrus sinensis (L.) Osbeck cv. Pêra Rio p de ser acompanhada pelas varia es anat micas nos meristemas apicais e axilares. Com objetivo de determinar a época na qual ocorre a indu o e evoca o floral, cortes longitudinais de gemas apicais e axilares, corados com pironina Y-methylgreen foram efetuados em períodos regulares de maio a agosto. Através das mudan as no formato da gema, principalmente diametro, que aumentou com a indu o, foi possível determinar a época do ano na qual gemas vegetativas s o induzidas a florescerem. Foram detectadas varia es nos diametros das gemas no período de início da morfogênese floral (meados até o final de julho). A medi o do diametro das gemas mostra-se um procedimento eficiente para acompanhar os fen menos decorrentes da indu o, evoca o e morfogênese florais. Gemas vegetativas apresentam diametro médio de 100μm, com túnica composta por três camadas, de formato c nico, recobrindo o corpo, ao passo que a reprodutiva é mais achatada, após a inicia o do primeiro primórdio de sépala, exibindo diametro médio de 200μm. Colora o com pironina Y-methylgreen proporciona a capta o do fen meno da evoca o floral, pela detec o de regi es mais concentradas em RNA, nas zonas periféricas das gemas; altera o bioquímica esta que precede a emiss o das sépalas.
Poliniza??o em cultura de laranja (Citrus sinensis L. Osbeck, var. Pera-Rio)
Malerbo-Souza, Darclet Teresinha;Nogueira-Couto, Regina Helena;Couto, Leomam Almeida;
Brazilian Journal of Veterinary Research and Animal Science , 2003, DOI: 10.1590/S1413-95962003000400001
Abstract: pollination in sweet orange crop, citrus sinensis l. osbeck, var. pera-rio. the present experiment was performed to study the frequency and behaviour of insects on sweet orange flowers, citrus sinensis (l.) osbeck, the effect these insects on fruit production (quantity and quality) besides measurements of the collection type of more frequent bees. during three consecutive years the more frequent insect visiting the flower was apis mellifera (africanized). the flowers visited by few or neither honey bees (until 9 visits) showed minor percentage of fruition. the fruit production was 35.30% greater in uncovered flowers. the mean weight of fruits was too greater in uncovered flowers (180.2g) than covered ones (168.5g). the fruits from the covered treatments were more acids (1.411g citric acid/100ml of juice) than uncovered ones (1.164g citric acid/100ml of juice). the number of seeds per bud was higher in uncovered treatment (1 seed/bud) than covered one (0.8 seed/bud).
Morfologia de embri?es nucelares de laranja 'Valência' (Citrus sinensis (L.) Osbeck)
Mendes-da-Glória, Fernanda Januzzi;Mour?o Filho, Francisco de Assis Alves;Appezzato-da-Glória, Beatriz;
Acta Botanica Brasilica , 2001, DOI: 10.1590/S0102-33062001000100003
Abstract: this research work evaluated the morphology of nucellar embryos of 'valencia' sweet orange (citrus sinensis (l.) osbeck), in an effort to provide this information as a reference in somatic embryo induction experiments, for in vitro breeding of this cultivar. embryos were collected from mature fruits (13 months after blooming), and were fixed, dehydrated and prepared for serial histological cuts. among the embryos, only one presented similar morphology to a zygotic embryo, whereas the others showed different shapes and angles in the cotyledons. not well formed embryos were also observed, mainly due to the lack of the differentiation of the shoot apex and/or root apex, undevelopment of one of the cotyledons, or sometimes due to the collapsed embryo. the results may contribute to a better understanding of different embryo morphologies of somatic embryos and their capacity to convert in plants.
Populational fluctuation of vectors of Xylella fastidiosa, wells in sweet orange [Citrus sinensis (L.) Osbeck] varieties of northwest Paraná State, Brazil
Molina, Rúbia de Oliveira;Gon?alves, Aline Maria Orbolato;Zanutto, Carlos Alexandre;Nunes, William Mário de Carvalho;
Brazilian Archives of Biology and Technology , 2010, DOI: 10.1590/S1516-89132010000300007
Abstract: the aim of the present study was to assess the population flutuation of the sharpshooters species subfamily cicadellinae belonging to the tribes cicadellini and proconiini, in sweet orange [citrus sinensis( l). osbeck] commercial orchards of the northwest region of paraná state , brazil. samplings were carried out the employing every time 24 yellow sticky cards. identification of the species showed that the most representative were dilobopterus costalimai of the cicadellini tribe and acrogonia citrina of the proconiini tribe.
Honey bee attractants and pollination in sweet orange, Citrus sinensis (L.) Osbeck, var. Pera-Rio
Malerbo-Souza, D. T.;Nogueira-Couto, R. H.;Couto, L. A.;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2004, DOI: 10.1590/S1678-91992004000200004
Abstract: this experiment studied the frequency and behavior of insects on sweet orange flowers, citrus sinensis (l.) osbeck, their effect on fruit production (quantity and quality), nectar and pollen collection, and the effectiveness of different attractants. over three consecutive years, the most frequent visitor to the flowers was apis mellifera (africanized). flowers visited less than ten times showed low fructification. fruit production was 35.30% greater in uncovered flowers. fruit mean weight was much greater in uncovered (180.2g) than in covered flowers (168.5g). fruits from the covered were more acid (1.411g of citric acid/100ml of juice) than the uncovered flowers (1.164g of citric acid/100ml of juice). the number of seeds per bud was higher in the uncovered (1 seed/bud) than in the covered treatment (0.8 seed/bud). bee-herer, eugenol, geraniol, citral, and lemon grass extract, mainly diluted in water, were effective in attracting honeybees to orchards. however, these compounds were less effective when diluted in sugar syrup. the same products had variable attractiveness to honeybees in different years.
Uso contínuo de herbicidas em citrus (Citrus sinensis (L ) Osbeck), I - efeitos no controle de plantas daninhas
Victoria Filho, Ricardo;Christoffoleti, Pedro Jacob;Ponchio, Joao Adolfo de Rezende;Takeda, Cláudio;Tomita, Nelson K.;
Planta Daninha , 1991, DOI: 10.1590/S0100-83581991000100010
Abstract: the research reported in this paper was conducted at the conchal county in sao paulo state, brazil, in a red yellow latosol with 1.75% of organic matter, with the objective of studyin g the effect of continuous use of selected herbicides on the weed control on a 'pena' citrus sinensis (l.) osbeck citrus orchard, graf ted on 'lim?o-cravo' (citrus limonia osbeck). kandon blocks experimental design with 12 treatments and 4 replicates was used. the treatments and herbicide application rates (kg/ha) were : terbacil at 3.2 sima zine at 4.0; ametryne + secbumetone at 4,5; dichlobeni l at 5.0; diuron at 3,2; bromacil at 3.2; bromacil at 3.2; bromacil + diuron at 3.2; paraqua t at 0.6; glyphosate at 1.61 and msma at 1.77 , and two cont rol plots manually til led, one year ly and the other whenever weeds covered 25% of the plot. the orchard was planted in may 1975, and the first herbicide application was done in october 1977. the area of each plot was 54 m2 (3.0 x 18.0 m) with 4 plants per plot. the last herbicide application was done in 1982. the effect of the treatments on weed control was evaluated through species couting and also visually. the herbicides used showed control ranging from acceptable to excellent, depending on the specific weed composition in the plot. the herbicides with best weed cont rol index as well as longer residual effects were bromacil + diuron, diuron bromacil, ametryne + secbumetone and terbacil. among the post-emergency her bicides the best indexes were obtained with glyphosa te and paraquat.
Analysis of expressed sequence tags from Citrus sinensis L. Osbeck infected with Xylella fastidiosa
Souza, Alessandra A. de;Takita, Marco A.;Coletta-Filho, Helvécio D.;Targon, Maria Luisa P.N.;Carlos, Eduardo F.;Locali-Fabris, Eliane C.;Amaral, Alexandre M.;Freitas-Astúa, Juliana;Silva-Pinhati, Ana Carla O.;Boscariol-Camargo, Raquel L.;Berger, Irving J.;Rodrigues, Carolina M.;Reis, Marcelo S.;Machado, Marcos A.;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000500023
Abstract: in order to understand the genetic responses resulting from physiological changes that occur in plants displaying citrus variegated chlorosis (cvc) symptoms, we adopted a strategy of comparing two est libraries from sweet orange [citrus sinensis (l.) osbeck]. one of them was prepared with plants showing typical cvc symptoms caused by xylella fastidiosa and the other with non-inoculated plants. we obtained 15,944 ests by sequencing the two cdna libraries. using an in silico hybridization strategy, 37 genes were found to have significant variation at the transcriptional level. within this subset, 21 were up-regulated and 16 were down-regulated in plants with cvc. the main functional categories of the down-regulated transcripts in plants with cvc were associated with metabolism, protein modification, energy and transport facilitation. the majority of the up-regulated transcripts were associated with metabolism and defense response. some transcripts associated with adaptation to stress conditions were up-regulated in plants with cvc and could explain why plants remain alive even under severe water and nutritional stress. others of the up-regulated transcripts are related to defense response suggesting that sweet orange plants activate their defense machinery. the genes associated with stress response might be expressed as part of a secondary response related to physiological alterations caused by the infection.
Características de la abscisión del fruto de Naranja Citrus sinensis (L.) Osbeck var. Salustiana
Libia E Laskowski Ochoa
Bioagro , 2006,
Abstract: El trabajo tuvo como objetivo establecer la cinética y características anatómicas de la abscisión de los frutos en Citrus sinensis (L.) Osbeck cultivar Salustiana durante el desarrollo inicial del fruto. Para el estudio se emplearon plantas de un huerto ubicado en Museros, en la provincia de Valencia, Espa a. En 25 árboles se etiquetaron 150 brotes uniflorales con hojas y se realizaron observaciones desde antesis hasta 104 días después de antesis desde marzo hasta julio. Se determinó el diámetro del fruto y para el estudio histológico se realizaron cortes en fresco en micrótomo de congelación. El crecimiento en diámetro se ajustó a una curva sigmoidal, registrándose una estrecha relación entre el incremento en la tasa de crecimiento del fruto y su abscisión relativa. En los frutos se identificaron tempranamente tres zonas de abscisión, una para la caída del estilo/eje floral y dos para el ovario y frutos jóvenes, las cuales se activaron a medida que progresó el desarrollo del fruto. The kinetics and anatomy of abscission were studied during the initial development of fruits of sweet orange Salustiana (Citrus sinensis (L). One hundred and fifty unifloral leafy shoots were labelled in 25 trees in an orchard located in Museros (Valencia, Spain) to follow the development from anthesis to 104 days after anthesis (daa), from March to July. The fruit diameter was measured and the histology was recorded in fresh made slides from a freezing microtome. The growth in diameter followed a sigmoidal curve with a close relation between the rate of fruit growth and its relative abscission. Three abscission zones were identified early in the fruitlets; one for the drop of the style/floral axis and two for the ovary/fruitlet which activated as progress the fruit development.
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