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Jaime Aguayo Cline Fourrier‐Jeandel Xavier Capdevielle Fabrice Vtillard Dominique Piou Eugenia Iturritxa Ccile Robin 《Forest Pathology》2020,50(1)
Fusarium circinatum is the causal agent of pitch canker, a destructive disease that threatens natural and planted pine forests around the world. Although pitch canker has caused problems in Spain and Portugal, concerning Europe as a whole, the fungus is not established across the pine distribution area. Its dispersion by wind and/or insect vectors could nevertheless play a role in the colonization of currently uninfected stands. It is therefore crucial to develop monitoring tools for its detection. To this end, we assessed the molecular detection of the pathogen in environmental samples of bark beetles and passive spore traps, collected in two infected Pinus radiata plantations in Basque country, Spain. The spread pattern of F. circinatum was assessed by an experimental design that included insect and spore traps installed at the centre, at the edge and outside the plots. Our results showed that F. circinatum was detected in both types of samples, at almost all collection dates. In both type of samples, positive detections were mainly found at the centre of the plots, a lower proportion at the edge, and very few outside. This suggests that long‐distance dispersion of Fusarium circinatum does not rely on wind spore dispersal neither on insect flight. Our study also shows that molecular methods are a powerful tool to monitor the pathogen in environmental samples. 相似文献
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Correlation of molecular markers and biological properties in Verticillium dahliae and the possible origins of some isolates 总被引:1,自引:0,他引:1
A. Collins J. Mercado-Blanco R. M. Jiménez-Díaz C. Olivares E. Clewes D. J. Barbara † 《Plant pathology》2005,54(4):549-557
Haploid and amphihaploid Verticillium dahliae isolates were studied using PCR-based molecular markers which: (i) discriminate the defoliating and nondefoliating pathotypes (two primer pairs INTD2f/r and INTND2f/r), and (ii) are species-specific (primer pair 19/22). The results were compared with some known biological and other molecular properties of the isolates. Five discrete sequences of the 19/22 amplicon were found. Sequence 4 was associated with both defoliating isolates from Spain and nondefoliating isolates from Spain and USA; these pathotypes were separated by the primer pairs INTD2f/r and INTND2f/r, but the data showed that the primer espdef01 (derived from the 19/22 amplicon) cannot be used for this purpose. Amplicon sizes and sequences with primers 19/22 divided amphihaploid isolates from crucifers (thought to be interspecific hybrids) into those corresponding to the previously reported α and β groups. The β-group isolates had either sequence 4 or 5 (these two differing by a single base). The distinct amplicon sequence 3 given by the α-group isolates demonstrated that the V. dahliae -like 'parent' of this group was molecularly unlike any haploid isolate yet studied. The overall results are discussed in relation to phytosanitary considerations and the probability of defoliating or crucifer pathotypes arising de novo within Europe, either by selection or by interspecific hybridizations. 相似文献
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Jo?o A T Pigatto José L Laus Jaime M Santos Cristine Cerva Luciana S Cunha Valéria Ruoppolo Paulo S M Barros 《Journal of zoo and wildlife medicine》2005,36(4):702-705
The corneal endothelium is essential for the maintenance of the corneal transparency. The aim of this study was to examine the morphology of the endothelial surface and perform morphometric analysis of the normal corneal endothelial cells of the Magellanic penguin (Spheniscus magellanicus) using scanning electron microscopy. The present work demonstrates that the corneal endothelium of the Magellanic penguin is similar to those described in other vertebrates. 相似文献
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J. Chatterjee A.K.A. Mandal S.A. Ranade Jaime A. Teixeira da Silva S.K. Datta 《Scientia Horticulturae》2006
An attempt was made to understand the molecular systematics and genetic differences between 10 original chrysanthemum cultivars and 11 mutants. The similarity among the cultivars and mutants varied from 0.17 to 0.90 using RAPD analyses, a simple but efficient method to distinguish cultivars and to assess parentage. Two distinct groups were found. Two cultivars were present as a separate group showing differences from all other cultivars. Mutants with different flower colour could be identified at the molecular level using RAPD technique holding promise to identify unique genes as SCAR markers. A high genetic distance among the different chrysanthemums showed that there exists a possibility of introgressing new and novel genes from the chrysanthemum gene pool. 相似文献
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Francisco J. Escobedo David J. Nowak John E. Wagner Carmen Luz De la Maza Manuel Rodríguez Daniel E. Crane Jaime Hernndez 《Urban Forestry & Urban Greening》2006,4(3-4):105-114
Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas. 相似文献
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Martia Ferreira Ana Maseda Jaime Fbregas Ana Otero 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):126-130
The effect of semi-continuous culture on the nutritional value of microalgae was tested in the rotifer Brachionus plicatilis in short-term enrichment experiments. Isochrysis aff. galbana clone T-ISO was cultured semi-continuously with renewal rates from 10 to 50% of the volume of the culture per day and used to feed the rotifers. After 24 h, dramatic differences in dry weight and protein, lipid and carbohydrate contents were observed in the rotifers depending on the renewal rate applied to the microalgal culture. Rotifers fed T-ISO cultured with low renewal rates showed low dry weight and organic content, whereas rotifers fed microalgae from nutrient-sufficient, high renewal rate cultures showed higher dry weight and increases up to 60% in protein, 35% in lipid and 100% in carbohydrate contents. Feed conversion rate (FCR) and organic FCR decreased with increasing renewal rates, indicating a more efficient assimilation of the microalgal biomass obtained at high growth rates. The fatty acid profile of rotifers reflected that of T-ISO, with maximum content of polyunsaturated fatty acids (PUFAs), n-3 fatty acids and docosahexaenoic acid (DHA) being found in the rotifers fed microalgae from the renewal rate of 40%. Results demonstrate that the biochemical composition of B. plicatilis is strongly modified through the use of semi-continuous cultures of microalgae in short-term enrichment processes. This technique provides an excellent tool to improve the nutritional value of the live feed used in fish larvae cultures. 相似文献
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