Browsing by Author "Martins-Gomes, Carlos"
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- Application of anti-hail net in apple orchards: effects on fruits chemical characteristicsPublication . Martins-Gomes, Carlos; Pinto, Luís; Silva, Ermelinda; Martins, Sandra; Gonçalves, Alexandre; Brito, Cátia; Moutinho-Pereira, José; Rodrigues, M.A.; Correia, Carlos M.; Nunes, Fernando M.Apple production in Portugal, over the last 15 years, has been subjected to increasing crop damage due to hailstorms and related meteorological extreme conditions. This problem has led farmers and researchers to find practical solutions to protect the orchards, such is the case of netting devices. The application of anti-hail nets in apple tree orchards looks to provide protection against the roughest meteorological events (such as hail, strong winds, and sunburn), while avoiding to upset the development of the plant and or, if possible, helping to improve the plant’s productivity. During 2016, this work was carried out in Carrazeda de Ansiães, a northeast Portuguese plateau zone that is a primary location for apple production, and the application of a grey anti-hail net, which reduces photosynthetically active radiation by 12 %, was tested in an orchard with the cultivars Golden delicious and Fuji of apple tree (Malus domestica Borkh). Control without screen net applied was also used. In order to understand the effects of the net, apples were collected and analysed for their chemical characteristics (total phenols, ortho-diphenols and flavonoids content, ABTS and polyphenolic profile). The obtained results in apple peel revealed, in both cultivars, a decrease in total phenols, ortho-diphenols and flavonoids concentration, whereas in the Fuji cultivar the antioxidant activity, determined by the ABTS assay, was maintained. Pulp results showed little difference with lower (P<0.001) ortho-diphenols content in Fuji cultivar and slightly lower (P<0.05) ABTS activity in Golden delicious cultivar. Peel and pulp methanolic extracts were analysed by HPLC-DAD. The phenolic profile was similar for both cultivars, with the exception of anthocyanins, being identified chlorogenic acid and derivatives of quercetin. The antihail net did not affect the phenolic profile, only decreased the polyphenols concentration. The use of a grey anti-hail net on apple orchards is a suitable alternative for the protection of apple trees against hail ensuring the production of the crop without compromising fruit quality.
- Combining zeolites with early-maturing annual legume cover crops in rainfed orchards: effects on yield, fatty acid composition and polyphenolic profile of olives and olive oilPublication . Martins, Sandra; Silva, Ermelinda; Brito, Cátia; Pinto, Luís; Martins-Gomes, Carlos; Gonçalves, Alexandre; Arrobas, Margarida; Rodrigues, M.A.; Correia, Carlos M.; Nunes, Fernando M.Under climate change threats, there is a growing need to adapt the conventional agronomic practices used in rainfed olive orchards by sustainable practices, in order to ensure adequate crop yield and olive oil quality and to preserve soil health. Therefore, for two years, the effects of conventional tillage practice (T) and two sustainable soil management strategies, a leguminous cover crop (LC) and its combination with natural zeolites (ZL), on the yield, fatty acid composition, polyphenolic profile and quality indices of olive fruits and oil were evaluated. Crop yield was significantly increased by LC and ZL in the first year. Although in the second year no significant differences were verified, the cumulative yield increased significantly by 31.6% and 35.5% in LC and ZL trees, respectively. LC enhanced the moisture and size of olives, while ZL increased, in general, the concentrations of oleuropein, verbascoside, caffeic acid and epicatechin, as well the oleic/linoleic ratio in fruits and the levels of 3,4-dihydroxyphenylglycol, tyrosol, verbascoside and caffeic acid in olive oil. Despite the higher concentration of total phenols in the fruits and oil from T trees in the warmer and dryer year, the quality of the oil decreased, mainly when compared with ZL, as evidenced by the peroxide value and K232 and K270 coefficients. In short, both sustainable soil management strategies appear to be promising practices to implement in olive orchards under rainfed conditions, but the innovative strategy of combining zeolites with legume cover crops, first reported in the present study, confers advantages from a nutritional and technological point of view. Nevertheless, studies subjected to the long-term use of these practices should be conducted to ensure the sustainability of the crop yield and olive oil quality.
- Improving the sustainability of rainfed olive orchards by using zeolites and early-maturing annual legumes cover cropPublication . Martins, Sandra; Silva, Ermelinda; Brito, Cátia; Pinto, Luís; Martins-Gomes, Carlos; Gonçalves, Alexandre; Arrobas, Margarida; Rodrigues, M.A.; Correia, Carlos M.Olive cultivation is considered as one of the most significant agricultural activities in Mediterranean region, from a financial, social and ecological point of view. Under climate change threats, there is a growing need to adapt the conventional agronomic practices used in rainfed olive orchards by sustainable practices, in order to preserve soil health, while ensure olive tree performance and olive oil quality. During three years, the effects of leguminous cover crops (LC) and its combination with zeolites (ZL) were evaluated on soil properties, olive tree physiological performance, yield, composition and quality of olive fruits and oil, and compared with soil tillage (T). Results show that both LC and ZL strategies were able to improve photosynthetic performance and crop yield, relatively to T. However, ZL strategy was clearly more efficient in improving soil quality, through decreasing acidity, improving soil N, P and B availability, CEC and soil microbiology. Considering the effects of these practices on olive fruit and oil composition, ZL increased the oleic/linoleic ratio on fruits, and the levels of 3,4-dihydroxyphenylglycol, tyrosol, verbascoside and caffeic acid on olive oil. In short, both sustainable soil management strategies appear to be promising practices to implement in olive orchards under rainfed conditions, but the innovative strategy of combining zeolites with legumes cover crops confer advantages from a nutritional and technological point of view, while preserving soil quality. Nevertheless, studies subjected to long-term use of these practices should be experienced to ensure the sustainability of crop yield and olive oil quality
- Olive tree physiology and chemical composition of fruits are modulated by different deficit irrigation strategiesPublication . Gonçalves, Alexandre; Silva, Ermelinda; Brito, Cátia; Martins, Sandra; Pinto, Luís; Dinis, Lia Tânia; Luzio, Ana; Martins-Gomes, Carlos; Fernandes-Silva, Anabela; Ribeiro, Carlos; Rodrigues, M.A.; Moutinho-Pereira, José; Nunes, Fernando M.; Correia, Carlos M.To overcome constrains affecting olive groves, cropping practices focusing on agronomic water use efficiency and their impact on quality parameters must be investigated. We evaluated the response of olive trees (Olea europaea, cv. Cobrançosa) to different water regimes, full irrigation (FI, 100% ETc) and three deficit irrigation strategies (DIS) (regulated (RDI, irrigated with 80% of crop evapotranspiration (ETc) in phases I and III of fruit growth and 10% of ETc in the pit hardening stage) and two continuous sustained strategies (SDI), a conventional SDI (27.5% of ETc), and a lowfrequency irrigation adopted by the farmer (SDIAF, 21.2% of ETc). RESULTS The effects of water regimes on the plant water status, photosynthetic performance, metabolites fluctuations and fruit quality parameters were evaluated. All DIS treatments enhanced leaf tissue density, RDI and SDI generally did not affect leaf water status and maintained photosynthetic machinery working properly, while SDIAF treatment impaired olive tree physiological indicators. DIS treatments maintained the levels of primary metabolites in leaves, but SDIAF plants showed signs of oxidative stress. Moreover, DIS treatments led to changes in the secondary metabolism, both in leaves and in fruits, with increased total phenolic compounds, ortho-diphenols, and flavonoids concentrations, and higher total antioxidant capacity, as well higher oil content. Phenolic profiles showed the relevance of an early harvest in order to obtain higher oleuropein levels with associated higher health benefits. CONCLUSION Adequate DIS are essential for sustainable olive growing, as they enhance the competitiveness of the sector in terms of olive production and associated quality parameters.
- Soil amendment with Zeolites and Biochar influenced soil properties, photosynthetic performance and olive fruit and oil compositionPublication . Martins, Sandra; Silva, Ermelinda; Brito, Cátia; Martins-Gomes, Carlos; Gonçalves, Alexandre; Arrobas, Margarida; Rodrigues, M.A.; Nunes, Fernando M.; Correia, Carlos M.Olive orchards represent a key agricultural system in the Mediterranean basin. Soil degradation processes associated to unsustainable agronomic practices and climate change could severely impact the sustainability of Mediterranean rainfed olive orchards. In this context, soil amendments are important tools that can be used to enhance soil fertility for sustained environmental quality and plant performance. For two years, we evaluated, under rainfed conditions, the effects of a fertilizer compound (FC) and its combination with zeolites (ZL) and biochar (BC) amendments on soil moisture, photosynthetic activity, yield, fruit and oil composition and quality indices. Although no significant effects were observed on crop yield, the application of ZL and BC improved plant photosynthetic performance due to lower stomatal limitations. The effects on soil quality were more evident in ZL amendment, due to the reduction of acidity, and enhanced moisture, cation exchange capacity, microbial biomass carbon and enzymatic activity. Results relative to olive composition show that the polyphenolic content was strongly influenced by treatments. ZL improved fruit fatty acid composition and oil quality, while BC enhanced the concentrations of polyphenols with high nutritional value (3,4-dihydroxyphenylglycol, oleuropein and rutin). In contrast, olive oil from FC fruits showed the poorest quality. The applied soil amendments appear to be a promising sustainable strategy to implement in olive rainfed orchards, and can be an interesting complement to mineral fertilization, in order to promote soil quality, increase physiological performance and olive oil quality.
- Zeolites and Biochar modulate olive fruit and oil polyphenolic profilePublication . Martins, Sandra; Silva, Ermelinda; Brito, Cátia; Martins-Gomes, Carlos; Gonçalves, Alexandre; Arrobas, Margarida; Rodrigues, M.A.; Correia, Carlos M.; Nunes, Fernando M.Soil degradation processes and climate change threaten the sustainability of Mediterranean rainfed olive orchards, with repercussions on crop yield and quality of olives, olive oil and olive by-products. Using soil amendments can enhance soil fertility for sustained environmental quality and plant performance. For two years, we evaluated, under rainfed conditions, the effects of a fertilizer compound (FC) and its combination with zeolites (ZL) and biochar (BC) amendments on soil moisture, yield, fruit and oil polyphenols and quality indices. The polyphenolic composition was strongly influenced by treatments, although no effects were observed on crop yield. ZL improved soil moisture (average increase of 26.3% compared to FC), fruit fatty acid composition (increase of 12.4% in oleic/linoleic ratio in 2018) and oil quality, BC enhanced the concentrations of polyphenols with high nutritional value (average annual increase of 25.6, 84.8 and 11.6% for 3,4-dihydroxyphenylglycol, oleuropein and rutin, respectively). In contrast, olive oil from FC fruits showed the poorest quality, with oxidation and hydrolytic breakdown signals. The applied soil amendments appear to be a promising sustainable strategy to implement in olive rainfed orchards.