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There is growing interest for using Spectral Vegetation Indices (SVI) derived by Unmanned Aerial Vehicle (UAV) imagery as a fast and cost-efficient tool for plant phenotyping. The development of such tools is of paramount importance to continue progress through plant breeding, especially in the Mediterranean basin, where climate change is expected to further increase yield uncertainty. In the present study, Normalized Difference Vegetation Index (NDVI), Simple Ratio (SR) and Green Normalized Difference Vegetation Index (GNDVI) derived from UAV imagery were calculated for two consecutive years in a set of twenty durum wheat varieties grown under a water limited and heat stressed environment. Statistically significant differences between genotypes were observed for SVIs. GNDVI explained more variability than NDVI and SR, when recorded at booting. GNDVI was significantly correlated with grain yield when recorded at booting and anthesis during the 1st and 2nd year, respectively, while NDVI was correlated to grain yield when recorded at booting, but only for the 1st year. These results suggest that GNDVI has a better discriminating efficiency and can be a better predictor of yield when recorded at early reproductive stages. The predictive ability of SVIs was affected by plant phenology. Correlations of grain yield with SVIs were stronger as the correlations of SVIs with heading were weaker or not significant. NDVIs recorded at the experimental site were significantly correlated with grain yield of the same set of genotypes grown in other environments. Both positive and negative correlations were observed indicating that the environmental conditions during grain filling can affect the sign of the correlations. These findings highlight the potential use of SVIs derived by UAV imagery for durum wheat phenotyping under low yielding Mediterranean conditions.

Water stress is one of the most important yield constraints on crop productivity for many crops, and especially for maize, worldwide. In addition, climate change creates new challenges for crop adaptation as water stress appears even in areas where, until recently, there was an adequate water supply. The objective of the present study was to determine the effect of water availability on the morphological and physiological characteristics of maize, and also on the environmental cost under field conditions. The lowest water treatment (ET50) reduced leaf area index, plant height, chlorophyll content, assimilation rate and gas exchange parameters, photosynthetic efficiency, and silage yield. Furthermore, mild water stress (ΕΤ70) affected the characteristics that were studied but maintained a high crop yield. Moreover, the outputs/inputs ratio and energy efficiency showed similar trends, with the highest values under ΕΤ100 treatment and the lowest under ΕΤ50 treatment in two consecutive years. Therefore, the results of this study can be used by farmers in the Mediterranean area, who can maintain or improve their crop yield using a lower amount of water when the water supply is limited, thereby contributing to reducing the impact of global climate change and maintaining crop productivity.

Drought is one of the major yield constraints of crop productivity for many crops. In addition, nowadays, climate change creates new challenges for crop adaptation in stressful environments. The objective of the present study was to determine the effect of water stress on five cultivars of basil (Mrs Burns, Cinnamon, Sweet, Red Rubin, Thai) and whether water use efficiency (WUE) can be increased by using the appropriate cultivar. Water stress affected the fresh and dry weight and also the partitioning of dry matter to leaves, flowers, and stems. Also, there are cultivars, such as Mrs Burns and Sweet, which were not affected by the limited amount of water and continued to produce a high amount of dry matter and also showed high essential oil yield. Essential oil content was not affected by the irrigation; however, essential oil yield was affected by the irrigation, and the highest values were found at Mrs Burns. The water use efficiency was affected by the cultivar and irrigation level, and the highest was found at Mrs Burns. The results show that using appropriate cultivars basil can achieve higher WUE and allow saving water resources and utilizing fields in areas with limited water resources for irrigation.

Intercropping is the cultivation of two or more crop species in the same space for a considerable proportion of the growth period. Farmers use cultivars that were bred under monoculture and there are no cultivars that have been evaluated under intercropping systems. The objective of the present study was to evaluate different cultivars of pea and wheat on intercropping systems. The experiment was conducted for two successive growing seasons (2018–2019 and 2019–2020) at the University Farm of Aristotle University of Thessaloniki, Greece, using two cultivars of field pea and six cultivars of bread wheat, and all their mixture combinations. The growing seasons, the intercropping treatments, and the cultivars affected the grain yield, the yield components, and the land equivalent ratio (LER) and actual yield loss (AYL) values. The different cultivars showed different responses under the intercropping treatments, indicating that there are cultivars that show higher grain yield in mixtures. Based on the mean grain yield for both growing seasons, the mixture ‘Isard’–‘Mavragani’ showed higher grain yield by 86.5% and 55.7% compared with the mean grain yield of all other mixtures and monocultures, respectively. The total LER value of ‘Isard’–‘Mavragani’ was high in both years: 1.954 and 1.693 in 2018–2019 and 2019–2020, respectively. This multicriteria evaluation of winter wheat and field pea varieties exhibited the need for the selection of appropriate cultivars for intercropping systems that were previously assessed under intercropping conditions before their exploitation from the farmers.

Energy flows in perennial agro and natural ecosystems are essential and could be related to greenhouse gas emissions and increasing water demands. Energy indices and carbon and water footprint are useful tools in assessing the interaction between production systems and environmental impact inside Natura 2000 sites and enhancing ecosystem services. The main aims of this study were to determine and compare energy indices, carbon and water footprint of olive groves, orange and kiwi orchards, and grasslands within and between 2 years, located in a Natura 2000 site, using an adjusted life cycle assessment (LCA) method; and to illustrate the importance of farming systems to ecosystem services. Proportional stratified sampling was used to select 36 farm types (12 olive groves, 12 oranges, and 12 kiwi orchards) and 12 grasslands from the municipality of Amfilochia, western Greece, during 2018 and 2019. Descriptive data analysis, correlational analysis, ANOVA, and hierarchical cluster analysis (HCA) were used to summarize and analyze the data. The main energy contributors for the three farm types were fertilizers and fuel consumption. The only input for the grasslands was animal manure. Energy efficiency showed the highest performance in olive groves followed in descending order by kiwi orchards, grasslands, and orange orchards. Concerning carbon-footprint, the values were the highest for orange orchards, followed in descending order by kiwi orchards, olive groves, and grasslands. Total water footprint values were the highest for grasslands and the lowest for olive groves. For both years, regarding HCA, each cluster consisted of the same ecosystems. According to the abovementioned indices, olive groves and grasslands are the most environmental friendly ecosystems. They could contribute in the environmental protection of the Amvrakikos Gulf, a Natura 2000 site. Kiwi orchards, although they are intensive along with the orange ones, seem to be more friendly to the environment than them and their cultivation in this Natura 2000 area is recommended. Energy indices and carbon and water footprint could be used, in order to highlight the related ecosystem (dis)services.

Arbuscular mycorrhizas (AM) are ubiquitous root symbioses with often pervasive effects on the plant host, one of which may be above- and belowground biomass allocation. A meta-analysis was conducted on 516 trials that were described in 90 available articles to examine whether AM colonization could result in a modification of partitioning of plant biomass in shoots and roots. It was hypothesized that alleviating plant nutrient limitations could result in a decrease of root to shoot (R/S) ratio in AM plants or, alternatively, the direction of shifts in the R/S ratio would be determined by the changes in total dry biomass. In our analysis, we considered four types of stresses: drought stress, single heavy metal stress, multiple heavy metal stress, and other potential abiotic plant stress factors. When disregarding any factors that could regulate effects, including stress status and mode of propagation, the overall AM effect was a significant modification of biomass towards shoot growth. However, the responses of stressed and clonally propagated plants differed from those of seed-grown unstressed plants. Our meta-analysis detected a considerable decline in the R/S ratio when plants were grown from seeds in the absence of abiotic stresses. Moreover, we demonstrate that additional regulators of the AM-mediated impact on R/S ratio were presence of competition from other plants, plant growth outcome of the symbiosis, growth substrate volume, experimental duration, and the identities of both plant and AM fungus. Our results indicate that a prediction of AM effects on R/S allocation becomes more accurate when considering regulators, most notably propagation mode and stress. We discuss possible mechanisms through which stress and other regulators may operate.

Water stress in one of the most important abiotic stresses that affects the productivity of many crop species worldwide. In addition, the climate change creates new challenges for crop adaptation especially as water resources become limited and the increase in water stress becomes more pronounced even in areas where there is adequate water supply. The objective of the present study was to determine the effect of water stress on physiological characteristics of five cultivars of basil under field conditions. Water stress affected leaf temperature, dry herb yield, leaf water potential, assimilation rate and gas exchange parameters, quantum yield, instantaneous water use efficiency (WUE), and essential oil content. From the physiological characteristics water potential and assimilation rate can be used for the selection of basil cultivars tolerant to water stress. In addition, essential oil content was lower under water stress indicating that essential oil content is correlated with water availability. From the present study it is obvious that there are tolerant basil cultivars to water stress and can be found using physiological traits such as water potential and assimilation rate and can be used to save and use water more sustainable and also conserve the water resources.

Tooth wear (TW) is an irreversible and cumulative phenomenon causing aesthetic and functional compromise. Increasing wear has been associated with age, and various other factors have been reported to influence its type and/or severity both in individuals and groups. Increased TW may constitute a major future problem for the elderly. The present cross-sectional study aims at determining the prevalence of TW in senior citizens from Northern Greece and evaluating the patient-level associations between TW, periodontal condition, and sociodemographic factors. A sample of 363 dentate individuals, aged between 65 and 74 years, was considered according to the WHO guidelines for national pathfinder surveys and three different dentists examined the representative population groups from different urban and rural areas in Northern Greece. The examiners were calibrated prior to the survey, with an interexaminer agreement of over 85%. The simplified TWI, community periodontal index (CPI), attachment loss (AL), plaque index (DI), calculus index (CI), and sociodemographic factors were detected and measured. TW is very prevalent among senior citizens in Northern Greece, with males having been found to experience more wear. Age and oral health status, when measured by the periodontal indices AL, DI, and CI, are significantly combined with TW in both urban and rural areas.

Introducing non- or under-utilized crops to cultivation generates benefits such as biodiversity enrichment, supporting mitigation actions towards climate change-induced effects. The salinization of soil and water supplies is progressively disrupting natural habitats and food production, especially in regions such as the Mediterranean. Sonchus oleraceus L. is a Mediterranean wild leafy green with nutritional and medicinal properties. This study’s purpose was to determine whether salinity affects the growth, quality, and nutrient composition of Sonchus oleraceus L. In an unheated plastic greenhouse, seedlings were transplanted in pots filled with perlite and irrigated with a nutrient solution with no NaCl added (the control, C) or with the addition of 40, 60, 80, and 100 mM of NaCl (treatments S4, S6, S8, and S10, respectively). The leaf and root growth, leaf quality, and the nutrient composition of leaves and roots were determined. Regarding the results, growth was mainly affected at high salinity levels (S8 and S10), with no observed effects of salinity on the determined quality parameters. The nutrient composition was variably affected by salinity in leaves but not in roots (except in the case of Na and the K/Na ratio). Sonchus oleraceus L. showed a general relative tolerance in moderate salinity levels (40 and 60 mM of NaCl), suggesting potential commercial exploitation of the species in areas where the quality of irrigation water is low. However, the health effects of consuming this species grown under salinity stress need to be studied in future research.

Basil (Ocimum basilicum L.) is an aromatic and medicinal plant with important properties and is used as an alternative crop in many countries of the world because of its medicinal, economic, industrial, and nutritional importance. The objective of the present study was to determine the effect of low water availability on seed production and seed quality of five cultivars of basil (Mrs Burns, Cinnamon, Sweet, Red Rubin, and Thai). Irrigation levels and cultivars affected seed yield and thousand seed weight. In addition, plants that were exposed to low water availability produced seeds that germinated in a greater percentage. Additionally, root length was increased as the PEG concentration was increased in the germination solution and was affected by the low water availability of the mother plants. The length of the shoot, the length of the root and the seed vigor could not be used as indicators of low water availability on the mother plants, but these characteristics and especially the seed vigor could be used as indicators of low water availability of the seed. Furthermore, the root length and the seed vigor indicated that there is a possibility of an epigenetic effect of water availability on the seed produced under low water availability, though more work is needed.