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Nunes E.W.L.P.,Rural University | Preston H.A.P.,Rural University | Dovale J.C.,Federal University of Ceara | Aragao F.A.S.D.,Embrapa Agroindustria Tropical CNPAT | And 2 more authors.
Crop Breeding and Applied Biotechnology | Year: 2015

The aim of this study was to identify sources of resistance to Myrothecium roridum and Podosphaeria xanthii. Initially, 86 inbred lines of the crossing AM-04 x Goldex, 91 inbred lines of the crossing AM-12 x Rochedo, and 75 inbred lines of the crossing ACP x AF-646 were evaluated. The trials were carried out in a greenhouse in a randomized block design with five replications. Seventeen inbred lines were identified as resistant to M. roridum. These inbred lines, as well as the parents and seven differential cultivars (checks) were evaluated for the reaction to P. xanthii. Ten inbred lines were selected as moderately resistant to M. roridum and resistant to P. xanthii. © 2015, Brazilian Society of Plant Breeding. All right reserved.

Braun U.,Martin Luther University of Halle Wittenberg | Oliveira Freire F.D.C.,Embrapa Agroindustria Tropical CNPAT | Urtiaga R.,Apartado 546
Polish Botanical Journal | Year: 2010

Four new species of cercosporoid hyphomycetes are described: Passalora majewskii U. Braun & F. O. Freire on Sparattanthelium botocudorum Mart, and Pseudocercospora avicenniicola U. Braun & F. O. Freire on Avicennia geminans (L.) Stern, (both from Brazil), P. hilliana U. Braun on Helmholtzia glaberrima (Hook, f.) Caruel from New Zealand, and P. ureraeU. Braun & R. Urtiaga on Urera baccifera (L.) Gaudich. ex Wedd. from Venezuela. New records are given for Cercospora apii Fresen. s.l. on the new host Helmholtzia glaberrima in New Zealand, C. caleifolii Bat., J. Upadhyay & Netto on Calea sp. new to Venezuela, Pseudocercospora namae (Deam. & House) U. Braun & Crous new to Brazil on the new host Hydroleaspinosa L., and P. struthanthi Braun, F. O. Freire & N. Pons in Brazil on the new host Tripodanthus sp. The nomenclature of several species from Brazil, New Zealand and Venezuelapreviously assigned to Stenella Syd. is reassessed, and those species are reallocated to Zasmidium Fr.

Nascimento D.M.,Federal University of Ceara | Almeida J.S.,State University of Ceara | Dias A.F.,Instituto Federal Of Educacao | Figueiredo M.C.B.,Embrapa Agroindustria Tropical CNPAT | And 3 more authors.
Carbohydrate Polymers | Year: 2014

The aim of this work was to optimize the extraction of cellulose nanowhiskers (CNW) from unripe coconut husk fibers (CHF). The CHF was delignified using organosolv process, followed by alkaline bleaching (5% (w/w) H2O2 + 4% (w/w) NaOH; 50 °C, 90 min). The CHF was subsequently hydrolyzed with 30% (v/v) sulfuric acid (60°C, 360 min). The process yielded a partially delignified acetosolv cellulose pulp and acetic black liquor, from which the lignin was recovered. The CNW from the acetosolv pulp exhibited an average length of 172 ± 88 nm and a diameter of 8 ± 3 nm, (aspect ratio of 22 ± 8). The surface charge of the CNW was -33 mV, indicating a stable aqueous colloidal suspension. The nanocrystals presented physical characteristics close to those extracted from cellulose pulp made by CHF chlorine-pulping. This approach offers the additional advantage of extracting the lignin as an alternative to eradication. © 2014 Elsevier Ltd.

Pereira A.L.S.,Federal University of Ceara | Nascimento D.M.D.,Federal University of Ceara | Souza Filho M.D.S.M.,Embrapa Agroindustria Tropical CNPAT | Morais J.P.S.,Embrapa Algodao CNPA | And 4 more authors.
Carbohydrate Polymers | Year: 2014

Cellulose nanocrystals (CNCs) isolated from banana pseudostems fibers (BPF) of the Pacovan variety were used as fillers in a polyvinyl alcohol (PVOH) matrix to yield a nanocomposite. The fibers from the external fractions of the BPF were alkaline bleached and hydrolyzed under acidic conditions (H 2SO4 62% w/w, 70 min, 45 °C) to obtain CNCs with a length (L) of 135.0 ± 12.0 nm and a diameter (D) of 7.2 ± 1.9 nm to yield an aspect ratio (L/D) of 21.2. The CNCs were applied to PVOH films at different concentrations (0%, 1%, 3%, and 5% w/w, dry basis). With higher concentrations of CNCs, the water-vapor barrier of the films increased, while the optical properties changed very little. Increasing the concentration of the CNCs up to 3% significantly improved the mechanical properties of the nanocomposite. © 2014 Elsevier Ltd.

Pereira A.L.S.,Federal University of Ceara | do Nascimento D.M.,Federal University of Ceara | Souza M.S.M.,Embrapa Agroindustria Tropical CNPAT | Cassales A.R.,Embrapa Agroindustria Tropical CNPAT | And 4 more authors.
BioResources | Year: 2014

Agricultural residues represent a disposal problem and a biomass source for chemical production. Lignocellulosic composition varies in plants as a function of several factors such as physiological age and tissue function. Banana pseudostem is a large biomass resource that is usually wasted, in spite of the possibility that it can be used as a source of organic compounds such as cellulose and hemicelluloses. The aim of this paper is compare the lignocellulosic content and physicochemical properties of different sheaths of Pacovan banana pseudostems. The trunk was divided into four different fractions, from the outermost sheaths to the core of the structure. There was a significant difference between the lignocellulosic compositions of the fractions. The X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry measurements reflected this difference in the sheaths. These results indicate that the Pacovan banana pseudostem cannot be considered to be a uniform biomass, and future approaches to its use as a biorefinery feedstock must consider a preliminary separation of the sheaths prior to chemical extraction of organic components.

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