Assessment of grapevine sap flow and trunk diameter variations in Mediterranean climate using time series decomposition

Vitis vinifera L. is a plant species that depends highly on temperature and water availability. Excessively hot and dry conditions can undermine growth and threaten grapevine performance. In these situations, grapevines activate self-regulating mechanisms to respond to water stress by prioritizing their survival through stomatal control and water redistribution. The monitoring of these mechanisms, through the measurements of the trunk diameter fluctuations and sap flow, was made for ‘Touriga-Nacional’ planted in the Douro Demarcated Region (NE Portugal), during the 2017 growing season. Seasonal and trend decomposition of the acquired data, as well as the assessment of the potential influence of meteorological variables was carried out, using locally estimated weighted regression and scatterplot smoothing. The objective behind this decomposition was to assess if the individual analysis of the periodic and inter-daily variations of the grapevine's trunk diameter fluctuations and sap flow could improve the understanding of their response to abiotic stress. The results have shown the methodology is efficient in extracting the different components and that their analysis is informative. It was possible to determine that the delay between the daily trunk diameter and sap flow periodic variations became shorter in time, suggesting the loss of water by transpiration is more easily observable under increasingly hotter and drier conditions. Furthermore, longerterm, inter-daily variations at the trunk are highly correlated with those of relative humidity, evidencing the impact of air moisture on their water status. Such findings justify the implementation of locally weighted regression and scatterplot smoothing (STL) in the operational processing of sap flow and trunk diameter time series in the control of grapevine water status, in the case of optimization of vineyard management by wine growers

Preparation and biological evaluation of ethionamide-mesoporous silicon nanoparticles against Mycobacterium tuberculosis

Ethionamide (ETH) is an important second-line antituberculosis drug used for the treatment of patients infected with multidrug-resistant Mycobacterium tuberculosis. Recently, we reported that the loading of ETH into thermally carbonized-porous silicon (TCPSi) nanoparticles enhanced the solubility and permeability of ETH at different pH-values and also increased its metabolization process. Based on these results, we synthesized carboxylic acid functionalized thermally hydrocarbonized porous silicon nanoparticles (UnTHCPSi NPs) conjugated with ETH and its antimicrobial effect was evaluated against Mycobacterium tuberculosis strain H37Rv. The activity of the conjugate was increased when compared to free-ETH, which suggests that the nature of the synergy between the NPs and ETH is likely due to the weakening of the bacterial cell wall that improves conjugate-penetration. These ETH-conjugated NPs have great potential in reducing dosing frequency of ETH in the treatment of multidrug-resistant tuberculosis (MDR-TB). (C) 2016 Elsevier Ltd. All rights reserved.Fundação para a Ciência e Tecnologia (FCT, Portugal) and FEDER (European Union) for funding through UID/MULTI/04378/2013, project grant IF/00092/2014 and IF2014 position. Thanks are also due to “Comissão de Coordenação e Desenvolvimento Regional do Norte (CCDR-N)/NORTE2020/Portugal 2020” for funding through project DESignBIOtechHealth (ref. Norte-01-0145-FEDER-000024). H.A.S. acknowledges financial support from the Academy of Finland (decision nos. 252215 and 281300), the University of Helsinki Research Funds, the Biocentrum Helsinki, and the European Research Council under the European Union’s Seventh Framework Programme (FP/2007–2013, Grant No. 310892). The content is solely the responsibility of the authors and does not necessarily represent the official views of the FCT or CCDR-Ninfo:eu-repo/semantics/publishedVersio

Synergistic Use of Sentinel-2 and UAV Multispectral Data to Improve and Optimize Viticulture Management

The increasing use of geospatial information from satellites and unmanned aerial vehicles (UAVs) has been contributing to significant growth in the availability of instruments and methodologies for data acquisition and analysis. For better management of vineyards (and most crops), it is crucial to access the spatial-temporal variability. This knowledge throughout the vegetative cycle of any crop is crucial for more efficient management, but in the specific case of viticulture, this knowledge is even more relevant. Some research studies have been carried out in recent years, exploiting the advantage of satellite and UAV data, used individually or in combination, for crop management purposes. However, only a few studies explore the multi-temporal use of these two types of data, isolated or synergistically. This research aims to clearly identify the most suitable data and strategies to be adopted in specific stages of the vineyard phenological cycle. Sentinel-2 data from two vineyard plots, located in the Douro Demarcated Region (Portugal), are compared with UAV multispectral data under three distinct conditions: considering the whole vineyard plot; considering only the grapevine canopy; and considering inter-row areas (excluding all grapevine vegetation). The results show that data from both platforms are able to describe the vineyards’ variability throughout the vegetative growth but at different levels of detail. Sentinel-2 data can be used to map vineyard soil variability, whilst the higher spatial resolution of UAV-based data allows diverse types of applications. In conclusion, it should be noted that, depending on the intended use, each type of data, individually, is capable of providing important information for vineyard management

Synergistic Use of Sentinel-2 and UAV Multispectral Data to Improve and Optimize Viticulture Management

The increasing use of geospatial information from satellites and unmanned aerial vehicles (UAVs) has been contributing to significant growth in the availability of instruments and methodologies for data acquisition and analysis. For better management of vineyards (and most crops), it is crucial to access the spatial-temporal variability. This knowledge throughout the vegetative cycle of any crop is crucial for more efficient management, but in the specific case of viticulture, this knowledge is even more relevant. Some research studies have been carried out in recent years, exploiting the advantage of satellite and UAV data, used individually or in combination, for crop management purposes. However, only a few studies explore the multi-temporal use of these two types of data, isolated or synergistically. This research aims to clearly identify the most suitable data and strategies to be adopted in specific stages of the vineyard phenological cycle. Sentinel-2 data from two vineyard plots, located in the Douro Demarcated Region (Portugal), are compared with UAV multispectral data under three distinct conditions: considering the whole vineyard plot; considering only the grapevine canopy; and considering inter-row areas (excluding all grapevine vegetation). The results show that data from both platforms are able to describe the vineyards’ variability throughout the vegetative growth but at different levels of detail. Sentinel-2 data can be used to map vineyard soil variability, whilst the higher spatial resolution of UAV-based data allows diverse types of applications. In conclusion, it should be noted that, depending on the intended use, each type of data, individually, is capable of providing important information for vineyard management

Influence of Climate Change on Chestnut Trees: A Review

The chestnut tree (Castanea spp.) is an important resource worldwide. It is cultivated due to the high value of its fruits and wood. The evolution between Castanea biodiversity and humans has resulted in the spread of chestnut genetic diversity. In 2019, the chestnut tree area worldwide was approximately 596 × 103 ha for fruit production (Southern Europe, Southwestern United States of America, and Asia). In Europe 311 × 103 t were produced. Five genetic poles can be identified: three in Greece, the northwest coast of the Iberian Peninsula, and the rest of the Mediterranean. Over the years, there have been some productivity changes, in part associated with climate change. Climate is considered one of the main drivers of biodiversity and ecosystem change. In the future, new challenges associated with climate change are expected, which could threaten this crop. It is essential to identify the impacts of climate change on chestnut trees, improving the current understanding of climate-tree interconnections. To deal with these projected changes adaptation strategies must be planned. This manuscript demonstrates the impacts of climate change on chestnut cultivation, reviewing the most recent studies on the subject. Furthermore, an analysis of possible adaptation strategies against the potentially negative impacts was studied

Correction: Freitas et al. Influence of Climate Change on Chestnut Trees: A Review. Plants 2021, 10, 1463

In the original article [...

Climate Change Projections for Bioclimatic Distribution of <i>Castanea sativa</i> in Portugal

The chestnut tree is an important forestry species worldwide, as well as a valuable food resource. Over recent years, Portugal has shown an increasing trend in chestnut tree area, as well as increases in production, hinting at the socioeconomic relevance of this agro-forestry species. In this study, bioclimatic indices are applied to analyse the spatial distribution of chestnut trees in mainland Portugal, namely growing degree days (GDD; 1900–2400 °C), annual mean temperature (AMT; 8–15 °C), summer days with maximum temperature below 32 °C (NTX), and annual precipitation (PRE; 600–1600 mm). These indices are assessed for the baseline (IBERIA01, 1989–2005) and future climates (EURO-CORDEX: 2021–2040, 2041–2060, and 2061–2080) under two forcing pathways (RCP4.5 and RCP8.5), also taking into account the chestnut tree land cover. For the baseline, the GDD showed only 10% suitability for chestnut tree cultivation in southern Portugal, whereas much higher values are found in the north of the country, and at higher altitudes (50–90%). For the AMT, higher elevation areas in northern Portugal show almost 100% suitability. Concerning NTX, the suitability reduces from the west (100–90%) to the east (40%). Regarding PRE, the suitability is heterogeneous throughout the territory, with areas under 50%. A new Chestnut Suitability Index (CSI) was then computed, which incorporates information from the four previous indices. The CSI reveals a suitability ranging from 100 to 75% in the north, while central and southern Portugal show values from 25 to 50%. For future climates, a progressive reduction in CSI was found, particularly for RCP8.5 and in the long-term period. Changes in bioclimatic conditions may restrict the 100% suitability to a narrow area in the north of the country. These reductions in chestnut bioclimatic suitability may have socio-economic and ecological implications for the management of the important agro-forestry species

Climate Change Projections for Bioclimatic Distribution of Castanea sativa in Portugal

The chestnut tree is an important forestry species worldwide, as well as a valuable food resource. Over recent years, Portugal has shown an increasing trend in chestnut tree area, as well as increases in production, hinting at the socioeconomic relevance of this agro-forestry species. In this study, bioclimatic indices are applied to analyse the spatial distribution of chestnut trees in mainland Portugal, namely growing degree days (GDD; 1900&ndash;2400 &deg;C), annual mean temperature (AMT; 8&ndash;15 &deg;C), summer days with maximum temperature below 32 &deg;C (NTX), and annual precipitation (PRE; 600&ndash;1600 mm). These indices are assessed for the baseline (IBERIA01, 1989&ndash;2005) and future climates (EURO-CORDEX: 2021&ndash;2040, 2041&ndash;2060, and 2061&ndash;2080) under two forcing pathways (RCP4.5 and RCP8.5), also taking into account the chestnut tree land cover. For the baseline, the GDD showed only 10% suitability for chestnut tree cultivation in southern Portugal, whereas much higher values are found in the north of the country, and at higher altitudes (50&ndash;90%). For the AMT, higher elevation areas in northern Portugal show almost 100% suitability. Concerning NTX, the suitability reduces from the west (100&ndash;90%) to the east (40%). Regarding PRE, the suitability is heterogeneous throughout the territory, with areas under 50%. A new Chestnut Suitability Index (CSI) was then computed, which incorporates information from the four previous indices. The CSI reveals a suitability ranging from 100 to 75% in the north, while central and southern Portugal show values from 25 to 50%. For future climates, a progressive reduction in CSI was found, particularly for RCP8.5 and in the long-term period. Changes in bioclimatic conditions may restrict the 100% suitability to a narrow area in the north of the country. These reductions in chestnut bioclimatic suitability may have socio-economic and ecological implications for the management of the important agro-forestry species

Mediterranean viticulture in the context of climate change

The exposure of viticulture to climate change and extreme weather conditions makes the winemaking sector particularly vulnerable, being one of its major challenges in the current century. While grapevine is considered a highly tolerant crop to several abiotic stresses, Mediterranean areas are frequently affected by adverse environmental factors, namely water scarcity, heat and high irradiance, and are especially vulnerable to climate change. Due to the high socio-economic value of this sector in Europe, the study of adaptation strategies to mitigate the negative climate change impacts are of main importance for its sustainability and competitiveness. Adaptation strategies include all the set of actions and processes that can be performed in response to climate change. It is crucial to improve agronomic strategies to offset the loss of productivity and likely changes in production and fruit quality. It is important to look for new insights concerning response mechanisms to these stresses to advance with more effective and precise measures. These measures should be adjusted to local terroirs and regional climate change projections for the sustainable development of the winemaking sector. This review describes the direct climate change impacts (on phenology, physiology, yield and berry quality), risks, and uncertainties for Mediterranean viticulture, as well as a set of canopy, soil and water management practices that winegrowers can use to adapt their vines to warmer and drier conditions

CLIMATE CHANGE AND ADAPTATION STRATEGIES FOR VITICULTURE

Future climate in the Mediterranean grapevine growing regions will be characterized by severe summer conditions, with lower water availability, elevated temperature and elevated solar irradiance (visible and ultraviolet). These projected conditions are of utmost relevance for agricultural practices, since greatly influence the growth and yield, as they exhibit additive and interactive effects on plant physiology. Therefore, it is crucial to develop short-term autonomous adaptation measures, both by economic and environmental sustainability reasons. With this in mind, the protective role of foliar kaolin clay particles (KL) application in the most important Portuguese wine area (Douro region) was examined. The results obtained in 2012 season revealed that KL had a significant positive effect on leaf temperature, stomatal conductance, net photosynthesis, intrinsic water use efficiency, photosynthetic pigments and yield. Thus, kaolin proved to be effective in alleviating the negative effects of summer stress