Browsing by Author "Vega, Alberto"
Now showing 1 - 10 of 14
Results Per Page
Sort Options
- Approach to phytotechnology regulatory and market trends in Europe: future perspectivesPublication . Vega, Alberto; Pereira, Sofia I. A.; Moreira, Helena; Ávila, Paula; Ferreira, Adelaide; Castro, Paula M. L.
- Assessment of metal(loid)s phytoavailability in mining soilsPublication . Ávila, Paula F.; Ferreira, Adelaide; Moreira, Helena; Pereira, Sofia I. A.; Vega, Alberto; Candeias, Carla; Castro, Paula M. L.
- Assessment of metalloids phytoavailability in mining soilsPublication . Ávila, Paula F.; Ferreira, Adelaide; Moreira, Helena; Pereira, Sofia I. A.; Vega, Alberto; Candeias, Carla; Castro, Paula M. L.
- Bioinoculants as plants allies in phytotechnological approaches to soil requalificationPublication . Moreira, Helena; Pereira, Sofia I. A.; Vega, Alberto; Ávila, Paula; Castro, Paula M. L.Introduction: Soil functions and quality have been adversely affected by anthropogenic activities (eg. mining), and the resulting contamination is a serious and crosscutting problem in several countries, including those in the SUDOE territory (Portugal, Spain and France). The urgent need for soil protection and conservation and the development of sustainable technologies to ensure the restoration of their environmental functionalities and services are a priority in European and national research programs and legislation. The PhytoSUDOE project aims to boost the environmental, economical and social benefits generated trough the implementation of phytotechnologies in degraded sites as a way to encourage their greater use by owners and policy-makers. A transnational network of contaminated sites throughout the SUDOE region (11 sites) was established to demonstrate different strategies. Objectives: The Borralha mine integrates soils with high TE (trace elements) concentrations. Energy crops such as sunflower and poplar can bring economic value to this area. Microorganisms such as mycorrhizal fungi (MF) and plant growth promoting bacteria (PGPR) that stimulate crop growth may benefit these plants by reducing the stress promoted by the contamination. Associated with these plants, agronomic techniques such as intercropping with alfalfa and clover may increase soil organic matter, promoting the biological activity and nutritive status of soils. The main goal of the work is: to evaluate the potential of energy crops cropping systems and the application of microbial consortia in the improvement of the functionalities of soil in the Borralha mine; Specific objectives include: improving plant performance and soil functionality/diversity with the use of bioinoculants; assess the effect of biostimulants on plant performance and TE mobility and uptake. On-going work: Sunflower was be harvested in October and rhizospheric soil samples will be collected to determine the metal content. Also plant biomass, elongation and metal content in each plant section (root and shoots) will be assessed. Bioconcentration and translocation factors will be determined to assess the plant phytostabilization/phytoextraction abilities. Soil analysis to determine structural and functional diversity will be performed at the end of the experiment (middle of next year – 2018). For poplars, height and plant diameter will be evaluated at the end of the experiment. Rhizosperic samples will be also collected to determine the metal stabilization.
- Effect of bioinoculants and biochar on grapevine-associated soil microbial communitiesPublication . Pereira, Sofia I. A.; Moreira, Helena; Vega, Alberto; Cunha, Joaquim; Alves, Marta; Graça, António; Fontes, Natacha; Porto, João; Castro, Paula M. L.
- Effect of the inoculation of plant growth promoting bacteria on maize plants to improve their growth under drought stressPublication . Abreu, Daniela; Pereira, Sofia; Moreira, Helena; Vega, Alberto; Castro, PaulaBackground: According to the United Nations, by 2050 the world population will reach approximately 9.6 billion people, which implies a major challenge for the agricultural sector to improve crop production and to ensure food availability in the near future. However, global warming and bad agricultural practices are impairing food productivity. Drought is one of the major limiting factors for plant growth, causing dehydration and nutrient deficiency. Therefore, the application of sustainable practices in agriculture is essential to maintain soil fertility and to increase crop productivity. It has been demonstrated that plant growth promoting bacteria (PGPB) have positive effects on plants growing under drought conditions. The aim of this work is to evaluate the effect of two PGPB inocula size on maize growth and nutrient content under different water regimes (80, 60 and 40% of soil water holding capacity (WHC)). Method: Thirteen PGPB were screened in vitro for osmotic tolerance and indole acetic acid (IAA) production under different osmotic potentials. Strains Pseudomonas fluorescens S3X and Ralstonia eutropha 1C2 were inoculated in maize under greenhouse conditions. Different bacterial treatments and two inocula sizes (2.5 x 10 6 and 3.3 x 10 3 cell. g -1 dry weight) were applied on plants growing at 80, 60 and 40% of soil WHC. Plants were harvested after 13 weeks. Dry biomass and the accumulation of N and P on roots and shoots were determined. The activity of soil enzymes, such as catalase, and the fluorescein diacetate (FDA) hydrolysis were also evaluated. Results & Conclusions: Maize growth was affected by the water regimes applied, especially at 40% of WHC. Bacterial inoculation enhanced some biometric parameters at 80 and 60% of WHC, however, the effects observed were similar for both inocula size applied. It was observed a severe reduction of FDA activity at 40% WHC, which indicates that the microbial activity was negatively affected by low soil moisture.
- Grapevine growth response to bioinoculants and biochar applicationPublication . Pereira, Sofia; Moreira, Helena; Vega, Alberto; Couto, José; Porto, João; Fontes, Natacha; Graça, António; Castro, Paula M. L.Background: Grapevine is a perennial crop that is highly responsive to local environmental conditions and viticulture practices. Along with this, soil microorganisms should be taken into consideration since they provide important ecological services to the plant. Plant growth promoting rhizobacteria and arbuscular mycorrhizal fungi can establish symbiotic association with grapevine roots and due to their plant-beneficial traits they can enhance the growth and quality of the vineyard and the grape. Therefore, the use of such microorganisms as bioinoculants can benefit vegetative and productive parameters of grapevine. Soil amendments, such as biochar, can also improve plant performance and soil structure. Biochar is a product of pyrolysis of organic materials and its importance as an amendment has been recognized in the improvement of soil fertility and water retention. This work aims to assess the effect of microbial inoculants and biochar on productive parameters of 10-year old grapevines and on vegetative parameters of new grapevines. Method: The experiment was conducted at a 36-ha vineyard located in North Portugal inside the Vinho Verde appellation, on adult (10 year-old) and on new grapevine plants. In total, 6 treatments with three replicates each were applied in the experimental area, in a total of 18 plots (variety Alvarinho). The treatments applied comprised different combinations of PGPR, AMF, and biochar. Bioinoculants and biochar were applied at the time of the plantation in the new grapevines. In the 10-year old grapevines, bioinoculants were inoculated around plants and a soil scarification was done between lines to apply biochar. Plant performance will be followed for at least 3 growing seasons. Results & Conclusions: The effect of bioinoculants and biochar application was evaluated at harvest. The number of grape bunches and total fruit yield were measured. Grape quality and nutrient content of 10-year old grapevines were assessed as well as biometric parameters of new grapevines. This is a multi-year project where successive inoculations are planned to enhance plant performance over the years.
- Inocula size and salinity stress impact PGPR outcomes on maize plantsPublication . Pereira, Sofia I. A.; Vega, Alberto; Sousa, Ana Sofia S.; Castro, Paula M. L.; Moreira, Helena
- Inocula size and salinity stress impact PGPR outcomes on maize plantsPublication . Pereira, Sofia; Vega, Alberto; Sousa, Ana Sofia; Castro, Paula; Moreira, HelenaFreshwater availability is an increasing problem for agriculture worldwide. Therefore, the use of saline water for crop irrigation is becoming a frequently used alternative, which can impact the yield of glycophytic crops such as maize. A promising strategy to attenuate the effects of salt on crop productivity could be the application of plant growthpromoting bacteria (PGPR). These bacteria can mitigate ion imbalances, improving the growth and nutritional status of maize plants, although these effects can depend upon the dose applied. This work aimed at evaluating the application of seven increasing inocula sizes of four PGPR - Cupriavidus necator 1C2, Chryseobacterium humi ECP37, Pseudomonas fluorescens S3X, and Pseudomonas reactans EDP28 - in maize growth under freshwater and saline water (5g NaCl/L) irrigation. Maize biomass, ion, and nutrient content were modeled in response to the different doses of bioinocula applied and the quality of the irrigation water. The impacts of the different treatments on some soil parameters, such as pH and electrical conductivity, were also assessed. Results showed that globally PGPR mitigated the effects of saline water irrigation in maize plants. However, the inoculum size produced a beneficial effect different for each strain, with some showing a better performance with shorter sizes. In addition, it was also observed that the beneficial effects were higher in plants growing under saline water irrigation. However, the inocula size(s) that produced the best outcomes under this condition did not correspond to the most benefited plants under freshwater irrigation. This study highlights the probability of inocula produce unpredicted effects on plants, which depend upon the number of cells applied and the imposed stress conditions.
- Phytotechnologies in degraded soils: the example of Borralha minePublication . Pereira, Sofia I. A.; Moreira, Helena; Vega, Alberto; Ávila, Paula; Ferreira, Adelaide; Castro, Paula M. L.Soil is a non-renewable natural resource and due to its increasing deterioration has been considered a target of environmental concern. Mining activities are one of the main contributors of trace elements (TE) inputs to soils worldwide. Relevant mining- related TE includes cadmium (Cd), zinc (Zn), copper (Cu), arsenic (As) and lead (Pb). The application of phytotechnologies (use of plants and associated microorganisms) in mining areas can mitigate TE contamination and dispersion and help in soils’ ecosystems restoration. Moreover, they can be integrated in phytomanagement systems (PS) that can provide relevant economic revenues by growing in those sites bioenergy crops (e.g. sunflower). The application of cropping patterns, as wintercropping, and bioinoculants, such as plant-growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) can optimize PS by enhancing plant yield, decrease plant stress and improve soil functionality.