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Kitajima E.W.,University of Sao Paulo | Rodrigues J.C.V.,University of Puerto Rico at San Juan | Rodrigues J.C.V.,CEPEL - Center of Pesquisas de Energia Eletrica | Freitas-Astua J.,Embrapa Mandioca e Fruticultura Tropical | Freitas-Astua J.,Centro APTA Citros Sylvio Moreira
Scientia Agricola | Year: 2010

The first cases of ornamental plants found infected by Brevipalpus transmitted viruses (BTV) were described in the 1990's from the region of Piracicaba, State of Sao Paulo, Brazil; subsequent cases were from other regions in the country and other American countries. Currently, 37 ornamental plant species (for the sake of simplicity, orchids being considered as a single species), belonging to 18 families of dicotyledons, have been reported hosting BTV. Because of the non systemic type of infection of these viruses, the localized diseases they cause are unimportant usually, but they have the potential to cause economic losses if severe outbreaks of Brevipalpus mite populations occur. Some ornamentals may serve as reservoirs to BTV known to cause serious damage to food crops as Citrus leprosis virus- cytoplasmic type (CiLV-C), passion fruit green spot virus (PFGSV) and Coffee ringspot virus (CoRSV).

Espinoza-Nunez E.,University of Sao Paulo | Mourao Filho F.A.A.,University of Sao Paulo | Stuchi E.S.,Embrapa Mandioca e Fruticultura Tropical | Cantuarias-Aviles T.,University of Sao Paulo | dos Santos Dias C.T.,University of Sao Paulo
Scientia Horticulturae | Year: 2011

Faced with new challenges, such as emerging diseases, shortening of orchard longevity, and larger social and environmental demands from consumers, practices such as rootstock diversification, irrigation and high density plantings have become relevant for the Brazilian citrus industry. This research had the objective to evaluate the performance of irrigated and non-irrigated 'Tahiti' lime trees grafted on 12 rootstocks and one interstock. Plots were distributed following a randomized block design, with four replicates and one plant per plot. Rootstocks influenced plant vigor, especially 'Flying Dragon' trifoliate, which reduced tree height by approximately 47% compared to the 'Rangpur' lime. Trees that were budded on more vigorous rootstocks showed higher yield when grown without irrigation than with irrigation. The '1646' citradia and 'Morton' citrange rootstocks performed particularly well. On the other hand, the plants on less vigorous rootstocks showed better performance in terms of yield under irrigation than the same combinations without irrigation, especially those grafted on the tetraploid 'Carrizo' and 'Troyer' citranges, 'Swingle' citrumelo, 'Davis A' trifoliate and 'Flying Dragon' trifoliate. Plants budded on the '1708' citradia had high yields under irrigated and non-irrigated conditions. The effect of interstock on plant vigor was dependent of rootstock. Interstocked plants on 'Davis A' trifoliate were higher than those without interstock. On the other hand, interstocked plants on Catania 2 'Volkamer' lemon were less vigorous than those without interstock. © 2011 Elsevier B.V.

de Sa A.J.,Federal University of Sergipe | da Ledo A.S.,Embrapa Tabuleiros Costeiros | da Silva Ledo C.A.,Embrapa Mandioca e Fruticultura Tropical
Ciencia Rural | Year: 2011

The mangaba tree (Hancornia speciosa Gomes) is a species whose natural occurrence has suffered great human pressure, which is causing genetic erosion in many populations, especially in the Northeast Brazil. Due to the existence of few collections of mangaba tree preserved ex situ, it's important to develop a complementary and alternative method to germplasm conservation of this species. The use of techniques of plant tissue culture for conservation of plant genetic resources presents several advantages over germplasm conservation in the field, especially when focusing cost reduction for the maintenance of collections, sanitary risk and weather problems. The present research aimed to evaluate the effectiveness of regulators osmotic mannitol and the growth inhibitor abscisic acid on the in vitro conservation of mangaba microcutting under slow growth. The cultures were maintained in MS medium with 3% sucrose and 0.6% of agar. The experiments were conducted in a randomized blocks design in a growth room with temperature ranging from 26±2°C, average relative humidity around 70% and photoperiod of 12 hours of cold white light (52μmol m-2 s-1 irradiance). It was evaluated five concentrations of mannitol (0, 10, 15 and 20g L-1). Mannitol in the presence of the length of shoots showed values below the control, but after 90 days of in vitro culture was observed deleterious effect of mannitol in microcutting. It was tested five concentrations of abscisic acid (0; 0.5; 1; 2 and 4mg L-1) in interaction with two types of sealing bottles (plastic cover and threaded aluminum foil) and two types of explants (apical and basal microcutting). Abscisic acid (0.5mg L-1) showed better results for in vitro conservation of seedling of mangaba microcutting grown in flasks sealed with aluminum foil. There was no significant effect of explant type.

Borges R.S.,State University Londrina | e Silva S.O.,Embrapa Mandioca e Fruticultura Tropical | de Oliveira F.T.,Instituto Paranaense Of Assistencia Tecnica E Extensao Rural Emater | Roberto S.R.,State University Londrina
Revista Brasileira de Fruticultura | Year: 2011

The aim of this work was to evaluate the performance of fourteen genotypes of banana tree, in the North Region of the state of Paraná, Brazil. The experiment was installed and carried out, without irrigation, in a commercial field located in Andirá, PR, Brazil, from 2007 to 2009. A completely randomized design with eight replications and one plant per parcel was used. The genotype FHIA 17 was outstanding of the rest presenting the best set of agronomic characters. The genotypes PA42-44, PV94-01 and 'BRS Princesa' presented similar characteristics to the comercial varieties 'Prata Anã', 'Pacovan' and 'Maçã', respectively, being alternatives of grow by its resistance to the black and yellow sigatokas and Fusarium wilt.

Cantuarias-Aviles T.,University of Sao Paulo | Mourao Filho F.d.A.A.,University of Sao Paulo | Stuchi E.S.,Embrapa Mandioca e Fruticultura Tropical | Silva S.R.d.,University of Sao Paulo | Espinoza-Nunez E.,University of Sao Paulo
Scientia Horticulturae | Year: 2010

The citriculture in Brazil, as well as in other important regions in the world, is based on very few mandarin cultivars. This fact leads to a short harvest period and higher prices for off-season fruit. The 'Okitsu' Satsuma (Citrus unshiu Marc.) is among the earliest ripening mandarin cultivars, and it is considered to be tolerant to citrus canker (Xanthomonas citri subsp. citri Schaad et al.) and to citrus variegated chlorosis (Xylella fastidiosa Wells et al.). Despite having regular fruit quality under hot climate conditions, the early fruit maturation and absence of seeds of 'Okitsu' fruits are well suited for the local market in the summer (December through March), when the availability of citrus fruits for fresh consumption is limited. Yet, only a few studies have been conducted in Brazil on rootstocks for 'Okitsu'. Consequently, a field trial was carried out in Bebedouro, São Paulo State, to evaluate the horticultural performance of 'Okitsu' Satsuma mandarin budded onto 12 rootstocks: the citrandarin 'Changsha' mandarin (Citrus reticulata Blanco) × Poncirus trifoliata 'English Small'; the hybrid Rangpur lime (Citrus limonia Osbeck) × 'Swingle' citrumelo (P. trifoliata (L.) Raf. × Citrus paradisi Macfad.); the trifoliates (P. trifoliata (L.) Raf.) 'Rubidoux', 'FCAV' and 'Flying Dragon' (P. trifoliata var. monstrosa); the mandarins 'Sun Chu Sha Kat' (C. reticulata Blanco) and 'Sunki' (Citrus sunki (Hayata) Hort. ex. Tanaka); the Rangpur limes (C. limonia Osbeck) 'Cravo Limeira' and 'Cravo FCAV'; 'Carrizo' citrange (Citrus sinensis × P. trifoliata), 'Swingle' citrumelo (P. trifoliata × C. paradisi), and 'Orlando' tangelo (C. paradisi × Citrus tangerina cv. 'Dancy'). The experimental grove was planted in 2001, using a 6 m × 3 m spacing, in a randomized block design. No supplementary irrigation was applied. Fruit yield, canopy volume, and fruit quality were assessed for each rootstock. A cluster multivariate analysis identified three different rootstock pairs with similar effects on plant growth, yield and fruit quality of 'Okitsu' mandarin. The 'Flying Dragon' trifoliate had a unique effect over the 'Okitsu' trees performance, inducing lower canopy volume and higher yield efficiency and fruit quality, and might be suitable for high-density plantings. The 'Cravo Limeira' and 'Cravo FCAV' Rangpur limes induced early-ripening of fruits, with low fruit quality. 'Sun Chu Sha Kat' and 'Sunki' mandarins and the 'Orlando' tangelo conferred lower yield efficiency and less content of soluble solids for the latter rootstock. © 2009 Elsevier B.V. All rights reserved.

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