Improvements in somatic embryogenesis protocol in Feijoa (Acca sellowiana (Berg) Burret): Induction,conversion and synthetic seeds     

Gabriela Claudia Cangahuala-Inocente  Lírio Luiz Dal Vesco  Douglas Steinmacher  Antonio Carlos Torres  Miguel Pedro Guerra 《Scientia Horticulturae》2007

Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA₃ (1 μM) and activated charcoal (1.5 g L⁻¹) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA₃ (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets.  相似文献   

Biological control ofBotrytis cinerea in residues and flowers of Rose (Rosa hybrida)     

Joseli da Silva Tatagiba  Luiz Antonio Maffia  Roberto W. Barreto  Acelino C. Alfenas  John C. Sutton 《Phytoparasitica》1998,26(1):8-19

Microbial isolates from living petals, petal residues and leaf residues of rose, and from laboratory collections, were evaluated for control ofBotrytis cinerea in rose. In leaf residues artificially infested withB. cinerea, isolates of the filamentous fungiGliocladium roseum, FR136 (unidentified) andTrichoderma inhamatum reduced sporulation of the pathogen by >90%, other filamentous fungi were 25–90% effective, and those of yeasts and bacteria were <50% effective. In artificially inoculated petal residues, no microbe reduced sporulation ofB. cinerea by >75%, but isolates ofCladosporium oxysporum and four yeasts were 51–75% effective, and three filamentous fungi, eight yeasts andBacillus subtilis isolates were 26–50% effective. Isolates ofT. inhamatum, C. oxysporum andG. roseum performed best againstB. cinerea among isolates evaluated in leaf residues naturally infested with the pathogen and indigenous microorganisms. Totals of ten isolates of filamentous fungi (includingC. oxysporum andC. cladosporioides), two of yeasts and five ofBacillus subtilis completely prevented lesion production byB. cinerea in detached petals, and a further six isolates of filamentous fungi (includingG. roseum) and six yeasts were 90–99% effective. Isolates ofC. oxysporum, C. cladosporioides andB. subtilis, the most effective microorganisms againstB. cinerea in flower buds, reduced number of lesions in the range of 42–65% compared with 59–89% for à standard fungicide (vinclozolin). It is suggested that application of leading antagonists Jo living rose leaves and flowers should optimize control of inoculum production byB. cinerea when the tissues die. Optimal biocontrol of lesion production in flower buds requires a better understanding of the microenvironment of petals.  相似文献   

Bekämpfung der wichtigsten Schädlinge der brasilianischen Landwirtschaft     

Luiz Gonzaga  E. Lordello  Domingos Gallo 《Journal of pest science》1954,27(4):49-55

Ohne ZusammenfassungDie Autoren sprechen Dr. Otto Schubart, Biologen der Estação Experimental de Biologia e Piscicultura, Pirassununga, Estado de São Paulo, ihren Dank aus für die Übersetzung dieses Artikels ins Deutsche, sowie Dr. Francisco A. Menezes Mariconi vom Instituto Biológico in São Paulo für verschiedene Ratschläge.  相似文献   

Effects of abrasive mineral, grit size and feed speed on the quality of sanded surfaces of sugar maple wood     

Luiz Fernando de Moura  Roger E. Hernández 《Wood Science and Technology》2006,40(6):517-530

Sanding is a common practice required in order to prepare wood surfaces for coating. Little literature is available regarding the effect of sanding parameters on the quality of surfaces. Sugar maple wood surfaces were evaluated in samples that had been sanded using two types of abrasive minerals, three grit sizes and four feed speeds. Roughness, wetting properties and cell damage were used to assess surface quality. Both abrasives decreased roughness and cell damage from 100- to 120-grit sanding stage. Addition of a 150-grit stage did not further reduce the roughness, whereas the cell damage continued to decrease. Increasing feed speed led to rougher surfaces due to higher fibrillation. Surfaces produced by silicon carbide were smoother and less damaged than those obtained with aluminum oxide. However, the surfaces sanded with aluminum oxide were more wettable and showed no significant difference in wetting time as a function of grit size. For these surfaces, the wetting time was reduced as feed speed increased.An erratum to this article is available at .An erratum to this article can be found at  相似文献   

Status of the genetic diversity and population structure of the Pêga donkey     

Mário Luiz Santana Jr.  Annaiza Braga Bignardi 《Tropical animal health and production》2015,47(8):1573-1580

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Reproductive and productive performances of Santa Inês ewes submitted to breeding in different periods of the Amazonian humid tropical climate     

Felipe Nogueira Soares  Maria Emilia Franco Oliveira  Luciana Cristina Padilha-Nakaghi  Luís Guilherme de Oliveira  Marcus Antônio Rossi Feliciano  Felipe Brener Bezerra de Oliveira  Pedro Paulo Maia Teixeira  Wilter Ricardo Russiano Vicente  Cristian Faturi  Luiz Fernando de Souza Rodrigues 《Tropical animal health and production》2015,47(8):1465-1471

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Cloning and characterization of gene-resistant analogs (RGAs) involved in rust (Puccinia psidii) resistance in Eucalyptus grandis     

Marcelo Luiz Laia  Acelino Couto Alfenas  Sergio Hermnio Brommonschenkel  Shinitiro Oda  Eduardo Jose de Melo  Inae Marie de Arau jo Silva  Janana Fernandes Goncalves  Ariadne Marques 《林业研究》2015,(3)

Disease-resistant genes play an important role in defending against a variety of pathogens and insect pests in plants. Most of the disease-resistant genes encode pro-teins with conserved leucine rich r...  相似文献   

Synthesis of 3-(4-Bromobenzyl)-5-(aryl methylene)-5H-furan-2-ones and their activity as inhibitors of the photosynthetic electron transport chain     

Barbosa LC  Rocha ME  Teixeira RR  Maltha CR  Forlani G 《Journal of agricultural and food chemistry》2007,55(21):8562-8569

A series of 12 3-(4-bromobenzyl)-5-(arylmethylene)-5 H-furan-2-one lactones, designed using the naturally occurring toxin nostoclides as a lead structure, were synthesized and screened as potential inhibitors of photosynthetic electron transport. The structures were confirmed by (1)H and (13)C NMR, MS, and IR analyses. Their biological activity was evaluated both in vitro, as the ability to interfere with light-driven reduction of ferricyanide by isolated spinach chloroplasts, and in vivo, as the capability to inhibite the oxygen production by intact Chlorella cells. Some of the compounds exhibited inhibitory properties in the micromolar range against basal and phosphorylating electron flow from water to K 3[Fe(CN) 6], with no effect on uncoupled electron flow. Thus, they seem to behave as energy-transfer inhibitors. Although poor solubility in water may limit their effectiveness, the active derivatives could present structures to be exploited for the design of new substances endowed with herbicidal activity.  相似文献   

Osteomalacia as a result of phosphorus deficiency in beef cattle grazing subtropical native pastures in Uruguay     

Carlos O. Schild  Fabiana M. Boabaid  Luiz G.S. Olivera  Mizael Machado  Ana Vildoza  Anderson Saravia  Alejandra Custodio  Carolina Command  Agustín Martinez  Martín Jaurena  Rob Dixon  Franklin Riet-Correa 《Journal of veterinary diagnostic investigation》2021,33(5):1018

We investigated 2 outbreaks of osteomalacia as a result of phosphorus (P) deficiency in herds of lactating beef cows grazing subtropical native pastures in Uruguay. Cows exhibited pica, difficulty to stand and walk, rib fractures, and body weight loss even with adequate forage availability. Osteopenia and severe osteomalacia were observed on gross and histologic examination. The concentrations of bicarbonate-extractable P in soil (4.0, 4.1 mg P/kg), total P in pasture (0.9, 1.1 g P/kg), inorganic P in serum (1.0, 0.71 mmol P/L), and P in bone (73 mg P/mL) were all low. Although injectable and mineral salt supplements provided additional P in both outbreaks, these supplementary amounts were insufficient to prevent P deficiency. The P ingested by the cows from the pasture and supplements would have provided 20–55% of their daily P requirements of ~21 g P/d. Osteomalacia occurred in cattle at the 2 ranches as a result of severe P deficiency in the soil and forage, and inadequate P supplementation. Following diagnosis, control of P deficiency in beef cattle requires estimation of the amount of pasture P ingested and provision of sufficient additional supplementary P to meet the animals’ requirements.  相似文献   

Yield map generation of perennial crops for fresh consumption     

Bazzi  Claudio Leones  Martins  Michel Rosin  Cordeiro  Bruno Eduardo  Gebler  Luciano  de Souza  Eduardo Godoy  Schenatto  Kelyn  de Paula Filho  Pedro Luiz  Sobjak  Ricardo 《Precision Agriculture》2022,23(2):698-711

Yield mapping technologies can help to increase the quantity and quality of agricultural production. Current systems only focus on the quantification of the harvest, but the quality has equal or greater importance in some perennial crops and impacts directly on the financial profitability. Therefore, a system was developed to quantify and relate the quality obtained in the classification line with the plants of the orchard and for decision-making. The system is comprised of hardware, which obtains the location of the harvester bag during harvesting and unloading at the unloading site, and software that processes the collected data. The cloud of real-time data contributed from the different collectors (bins) allows the construction of yield maps, considering the multi-stage harvesting system. Further, the system enables the creation of a detailed map of the plants and fruits harvested. As the harvest focuses on quality, it takes place in stages, depending on the ripening of the fruits. In addition to the yield maps, the system allows identification of the efficiency of each worker undertaking the harvest by the number of performed discharges and by the time spent. The system was developed in partnership with the Federal Technological University of Paraná and Embrapa Uva & Vinho and was tested in apple orchards in southern Brazil. Although the system was evaluated with only data from apple cultivation, monitoring the quality and quantifying other orchard fruits can positively impact the fruit sector.

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