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Aira M.,University of Vigo | Gomez-Brandon M.,University of Vigo | Gomez-Brandon M.,Lund University | Lazcano C.,University of Vigo | And 3 more authors.
Soil Biology and Biochemistry | Year: 2010

We studied the microbial communities in maize (Zea mays) rhizosphere to determine the extent to which their structure, biomass, activity and growth were influenced by plant genotype (su1 and sh2 genes) and the addition of standard and high doses of different types of fertilizer (inorganic, raw manure and vermicompost). For this purpose, we sampled the rhizosphere of maize plants at harvest, and analyzed the microbial community structure (PLFA analysis) and activity (basal respiration and bacterial and fungal growth rates). Discriminant analysis clearly differentiated rhizosphere microbial communities in relation to plant genotype. Although microorganisms clearly responded to dose of fertilization, the three fertilizers also contributed to differentiate rhizosphere microbial communities. Moreover, larger plants did not promoted higher biomass or microbial growth rates suggesting complex interactions between plants and fertilizers, probably as a result of the different performance of plant genotypes within fertilizer treatments, i.e. differences in the quality and/or composition of root exudates. © 2010 Elsevier Ltd.

Sieiro P.,Centro Tecnologico del Mar | Otero J.,CSIC - Institute of Marine Research | Guerra A.,CSIC - Institute of Marine Research
Hydrobiologia | Year: 2014

We contrasted histological characteristics with a macroscopic maturity scale in Octopus vulgaris. Seven histological stages of maturation were identified, and a stereological method was used to develop a new histological maturity index (HMI). This index was related to the gonadosomatic index giving the possibility to estimate the histological stage of individual octopus without sampling the gonads. However, the existing macroscopic maturity scale produced some degree of overlap along the range of HMI, suggesting that this macroscale at this moment might be just good enough to separate immature from fully mature individuals. A histological maturity criterion based on the presence of a larger proportion of folding oocytes compared to earlier microstages resulted in a size at maturity of 1.5 kg. However, using two different macroscopic criteria, size at maturity was 1.3 and 2.3 kg. The estimate of size at maturity is therefore sensitive to the maturity criteria used. The maturation cycle of female O. vulgaris was seasonal, peaking in spring months and reaching a maximum of reproductive activity in April independently of the maturation criteria used. Oogenesis was reviewed and found to be an asynchronic process. Our results suggest that there is a need to examine all these issues in other cephalopod species. © 2014 Springer International Publishing Switzerland.

Suris-Regueiro J.C.,University of Vigo | Santiago J.L.,Centro Tecnologico del Mar
Marine Policy | Year: 2014

The management of marine ecosystems requires adequate knowledge of both environmental and human dimensions, as well as their interrelationships. In this study, the aquaculture and fisheries activities are analyzed in one of most important fishing regions in Europe, Galicia (NW Spain). In particular, the intensity and characteristics of the fishing dependency are evaluated in terms of income and employment. Thus, nine marine economic activities for nine Maritime Zones have been defined, considering the social and economic relevance of the provided ecosystem services to these communities. This paper highlights the entire Galician coast as fishing-dependent, independently of the urbanization level. Furthermore, the contribution of different fishery segments to the income and employment of these coastal communities is reviewed, including fluctuations on whether the activity is small or large-scale. Finally, this study establishes a strong relationship among the marine activities, which generate most employment, and the regulatory framework of the Regional Government. Therefore, the conclusions are relevant to design and implement policies that affect Galicia[U+05F3]s Region and all its related marine ecosystems. © 2014 Elsevier Ltd.

Lazcano C.,University of Vigo | Lazcano C.,Centro Tecnologico del Mar | Revilla P.,Mision Biologica de Galicia CSIC | Malvar R.A.,Mision Biologica de Galicia CSIC | Dominguez J.,University of Vigo
Journal of the Science of Food and Agriculture | Year: 2011

BACKGROUND: Vermicompost has been proposed as a valuable fertilizer for sustainable agriculture. The effects of vermicompost on yield and quality of sweet corn were evaluated in this study. In two field trials, sweet corn plants were grown under (i) a conventional fertilization regime with inorganic fertilizer, and integrated fertilization regimes in which 75% of the nutrients were supplied by the inorganic fertilizer and 25% of the nutrients were supplied by either (ii) rabbit manure, or (iii) vermicompost. All three types of fertilization regime were supplied at two doses. Two pairs of nearly isogenic sweet corn hybrids homozygous for sugary1 and shrunken2 mutants were included in the trials to explore fertilizer × genotype interactions. Growth, yield and ear quality of the plants were evaluated in relation to the three fertilization regimes. RESULTS: In general, the integrated regimes yielded the same productivity levels as the conventional treatment. Moreover, both vermicompost and manure produced significant increases in plant growth and marketable yield, and also affected the chemical composition and quality of the marketable ear. Nevertheless, most of the observed effects of the organic fertilizers were genotype-dependent. CONCLUSION: The results confirm that the use of organic fertilizers such as vermicompost has a positive effect on crop yield and quality. Nevertheless, these effects were not general, indicating the complexity of the organic amendment-plant interactions and the importance of controlling genetic variation when studying the effects of vermicompost on plant growth. © 2011 Society of Chemical Industry.

Abollo E.,Centro Tecnologico del Mar
Diseases of Aquatic Organisms | Year: 2014

Bonamiosis is a disease affecting various oyster species and causing oyster mass mortalities worldwide. The protozoans Bonamia exitiosa and B. ostreae (Haplosporidia) are in - cluded in the list of notifiable diseases of the World Organisation for Animal Health as the causative agents of this disease. Although the geographic range of both species was considered different for years, both species are now known to co-occur in some European areas affecting the same host, Ostrea edulis, which strengthens the need of species-specific methods to unequivocally identify the species of Bonamia. An oligonucleotide probe for specific detection of B. Exitiosa (BEX-ITS) was designed to be used in in situ hybridisation (ISH) assays. ISH assay with BEX-ITS probe showed species-specificity and more sensitivity than traditional histology to visualise the parasite inside host tissue. ISH assay showed that the oyster gonad was the area where the parasite was most frequently located, and was the exclusive organ of infection in some oysters. A recommendation arising from the study is that more than 1 organ (including gonad and gills) should be used for PCR-based diagnosis of B. Exitiosa, to maximise the sensitivity. © Inter-Research 2014.

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