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991.
Ana?Belén?González-FernándezEmail author José?Ramón?Rodríguez-Pérez Enoc?Sanz?Ablanedo Celestino?Ordo?ez 《Precision Agriculture》2017,18(4):525-573
This study describes a method for vineyard zone delineation based on spatial interpolation of data on annual monitoring of grape and vine growth from 2007 to 2012 for four commercial vines (Cabernet Sauvignon, Mencía, Merlot and Tempranillo) located in the Bierzo Denomination of Origen (NW Spain). A sampled grid of 20 × 29 m (14 vines/ha) was defined for each vineyard and data were collected for ten soil, six grape composition, three grape production and five vine vigour variables. Continuous maps of each variable were created by spatial interpolation from the sampled points. Several zone delineations were obtained by clustering—using the iterative self-organizing data analysis (ISODATA) algorithm—according to different combinations of the studied variables. The resulting zone delineations were analysed (ANOVA) in order to determine whether the variables in the two cluster classifications for two or three zones were statistically different from each other. The selected delineation was the cluster that included total soluble solids, titratable acidity, total phenolic content, pH, mean cluster weight and length of the internode in two zones. The results point to the feasibility of this approach to vineyard zone delineation. Further research is necessary to confirm the effectiveness of this approach for other locations and evaluate the usefulness of introducing new grape and vine variables. 相似文献
992.
Spatial genetic structure and dispersal of the cacao pathogen Moniliophthora perniciosa in the Brazilian Amazon
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A. S. Artero J. Q. Silva P. S. B. Albuquerque E. A. Bressan G. A. Leal Jr A. M. Sebbenn G. W. Griffith A. Figueira 《Plant pathology》2017,66(6):912-923
Moniliophthora perniciosa is the causal agent of witches’ broom in Theobroma cacao (cacao). Three biotypes of M. perniciosa are recognized, differing in host specificity, with two causing symptoms on cacao or Solanaceae species (C‐ and S‐biotypes), and the third found growing endophytically on lianas (L‐biotype). The objectives of this study were to clarify the genetic relationship between the three biotypes, and to identify those regions in the Brazilian Amazon with the greatest genetic diversity for the C‐biotype. Phylogenetic reconstruction based on the rRNA ITS regions showed that the C‐ and S‐biotypes formed a well‐supported clade separated from the L‐biotype. Analysis of 131 isolates genotyped at 11 microsatellite loci found that S‐ and especially L‐biotypes showed a higher genetic diversity. A significant spatial genetic structure was detected for the C‐biotype populations in Amazonia for up to 137 km, suggesting ‘isolation by distance’ mode of dispersal. However, in regions containing extensive cacao plantings, C‐biotype populations were essentially ‘clonal’, as evidenced by high frequency of repeated multilocus genotypes. Among the Amazonian C‐biotype populations, Acre and West Amazon displayed the largest genotypic diversity and might be part of the centre of diversity of the fungus. The pathogen dispersal may have followed the direction of river flow downstream from Acre, Rondônia and West Amazon eastward to the rest of the Amazon valley, where cacao is not endemic. The Bahia population exhibited the lowest genotypic diversity, but high allele richness, suggesting multiple invasions, with origin assigned to Rondônia and West Amazon, possibly through isolates from the Lower Amazon population. 相似文献
993.
Letícia Aparecida de Moraes Julio Massaharu Marubayashi Valdir Atsushi Yuki Murad Ghanim Vinicius Henrique Bello Bruno Rossitto De Marchi Leonardo da Fonseca Barbosa Laura M. Boykin Renate Krause-Sakate Marcelo Agenor Pavan 《Phytoparasitica》2017,45(4):517-525
In Brazil, the first major invasion event of Bemisia tabaci was that of Middle East–Asia Minor 1 (MEAM1) species, formerly termed as B biotype, which commenced in the 1990s mainly by ornamental plants in São Paulo State. More than two decades after this invasion, the presence of the Mediterranean (MED) species of B. tabaci, formerly Q biotype, was reported in Rio Grande do Sul, the southernmost State of Brazil, and now in São Paulo and Paraná States, in southeastern Brazil. Specimens of whiteflies collected from commercial begonia, hydrangea, petunia and poinsettia greenhouses in São Paulo, and also from begonias and poinsettias collected in flower shops in Paraná, were all identified as belonging to MED species. Furthermore, the secondary endosymbionts Arsenophonus, Hamiltonella and Rickettsia of MED from São Paulo and Paraná were detected by PCR and their presence confirmed by sequencing and FISH analysis, and those results differed from MED detected in Rio Grande do Sul that harbored only Hamiltonella and Cardinium. Our results suggest a new MED invasion into Brazil and is associated with ornamental plants. The two MED populations are genetically different and suggest that they are separate invasions. 相似文献
994.
Vinicius de Abreu D’Ávila Elen de Lima Aguiar-Menezes Renato Nunes Pereira Vânia Gonçalves-Esteves Cláudia Barbieri Ferreira Mendonça Saulo José de Melo Tamires Medeiros dos Santos 《Phytoparasitica》2017,45(4):471-484
Coleomegilla maculata DeGeer is an omnivorous lady beetle that feeds on natural or alternative prey and artificial foods, which allows its laboratory rearing for use on augmentative biocontrol. In addition, C. maculata may supplement its diet with pollen and nectar, which helps in its conservation in agroecosystems. This study aimed to evaluate if Apiaceous flowers (Anethum graveolens L. and Coriadrum sativum L.), with and without alternative prey [eggs of Ephestia kuehniella (Zeller) or larvae of Drosophila melanogaster Meigen] or an artificial food (aqueous solution of honey), may guarantee the survival and complete development of the immature and adult stages of C. maculata in the laboratory. The immature stages developed only when Apiaceous flowers were offered with E. kuehniella eggs. The food with only one of the alternative prey (moth eggs or fly larvae) or moth eggs + honey solution resulted in fertile adults; however, the number of eggs/cluster was greater for the foods with E. kuehniella eggs + honey solution, A. graveolens flowers, or only D. melanogaster. Foods comprising only the two Apiaceous species, only the honey solution, or only water resulted in larval development up to a specific instar. Adults of C. maculata also survived on these foods, but there was no oviposition. The foods of the two Apiaceous species produced heavier adults only when associated with E. kuehniella eggs. The results indicate that the zoophytophagous habit of C. maculata should be considered in conservation biocontrol programs aimed at using this lady beetle to control crop pests. 相似文献
995.
Aurivan Soares Freitas Edson Ampélio Pozza Silvino Intra Moreira Maria Gilmara de Oliveira Soares Humberson Rocha Silva Eduardo Alves 《Phytoparasitica》2017,45(3):317-324
Yellow Sigatoka that is caused by Pseudocercospora musae is an important banana disease. The aim of this study was to elucidate the infection process of P. musae in banana leaves by scanning electron microscopy. Leaf samples were inoculated on the abaxial surface with P. musae and then analysed at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h post inoculation (hpi) and at 36 and 50 days post inoculation (dpi). The conidia were found to be germinated between 24 and 36 hpi and penetrated through the stomata between 96 and 120 hpi, or more generally from 144 hpi. P. musae colonized the spongy parenchyma at 36 dpi and the palisade parenchyma at 50 dpi. Sporulation occurred at 50 dpi on the adaxial surface of leaves through the emergence of conidia on conidiophores through the stomata. Considering the importance of yellow Sigatoka in banana production, our results provide a better understanding of the life cycle of the fungus for treatment processes. 相似文献
996.
Kelly Lana Araújo Silvaldo Felipe da Silveira Vicente Mussi-Dias Juan Manuel Anda Rocabado Flavio Costa Miguens 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(2):413-422
Two Camarotella (Phyllachoraceae) species, C. torrendiella and C. acrocomiae are the causative agents of small (SV) and large verrucosis (LV), respectively, which are important diseases affecting Brazilian coconut palms. The small verrucosis produces necrotic lesions in coconut palm leaflets, whereas LV just produces chlorosis. Semi-thin sections of asymptomatic leaflets and of leaves presenting stromata in different development stages were compared through light microscopy in order to characterize the colonization process of these two coconut palm verrucosis agents. Camarotella torrendiella initially colonized the adaxial epidermal cells and the cells underlying the epidermis close to the vascular bundles. In latter colonization stages, the hyphae of C. torrendiella remained limited to the underlying necrotic tissue adjacent to the mature stromata, mostly in the intracellular spaces and in the collapsing cells of necrotized tissues around the vascular bundles. This species does not colonize intracellular intact fiber cells, xylem vessels or phloem sieve tube elements. In contrast, C. acrocomiae presented a typical biotrophic parasitism model such as that of some gramineous Phyllachora spp. High densities of C. acrocomiae hyphae were found inside intact sieve tube elements; however, with no evidence of cellular death. The extensive hyphal colonization by C. acrocomiae within sieve tube elements was also observed in tertiary and quaternary bundles, as well as in anastomosing vascular bundles. The dependence of both species on the colonization sites associated with vascular bundles indicates the need for additional studies about these intricate host-pathogen relationships. These studies could be important to define new strategies to control coconut palm verrucosis diseases. 相似文献
997.
998.
Synthesis,theoretical studies,and effect on the photosynthetic electron transport of trifluoromethyl arylamides
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999.
de Oliveira Silva Alan Savi Daiani Cristina Raiser Paulo Henrique Schueda Gonçalves Fabrício Packer Kava Vanessa Galli-Terasawa Lygia Vitória Glienke Chirlei 《植物病害和植物保护杂志》2017,124(1):73-80
Journal of Plant Diseases and Protection - Citrus black spot (CBS) is a disease caused by the fungus Phyllosticta citricarpa that is associated with significant yield losses. The pathogen forms... 相似文献
1000.
Marcelo A. Araújo Maurício Deschk Juliana T. Wagatsuma Beatriz P. Floriano Carlos E. Siqueira Valéria NLS. Oliva Paulo SP. Santos 《Veterinary anaesthesia and analgesia》2017,44(4):854-864