Genetic Diversity and Range Dynamics of Helleborus odorus subsp. cyclophyllus under Different Climate Change Scenarios

Research Highlights: The effects of climate change on habitat loss, range shift and/or genetic impoverishment of mid-elevation plants has received less attention compared to alpine species. Moreover, genetic diversity patterns of mountain forest herbaceous species have scarcely been explored in the Balkans. In this context, our study is the first that aims to examine Helleborus odorus subsp. cyclophyllus, a medicinal plant endemic to the southern part of the Balkan Peninsula. Background and Objectives: We compare its genetic diversity and structure along the continuous mountain range of western Greece with the topographically less structured mountains of eastern Greece, and predict its present and future habitat suitability, using several environmental variables. Materials and Methods: Inter Simple Sequence Repeat (ISSR) markers were used to genotype 80 individuals from 8 populations, covering almost the species’ entire distribution range in Greece. We investigated the factors shaping its genetic composition and driving its current and future distribution. Results: High gene diversity (0.2239–0.3319), moderate population differentiation (0.0317–0.3316) and increased gene flow (Nm = 1.3098) was detected. According to any GCM/RCP/climate database combination, Helleborus odorus subsp. cyclophyllus is projected to lose a significant portion of its current distribution by 2070 and follow a trend towards genetic homogenization. Conclusions: Populations exhibit in terms of genetic structure a west–east genetic split, which becomes more evident southwards. This is mainly due to geographic/topographic factors and their interplay with Quaternary climatic oscillations, and to environmental constraints, which may have a negative impact on the species’ future distribution and genetic composition. Pindos mountain range seems to buffer climate change effects and will probably continue to host several populations. On the other hand, peripheral populations have lower genetic diversity compared to central populations, but still hold significant evolutionary potential due to the private alleles they maintain

Monitoring of Volatile Organic Compounds in Strawberry Genotypes over the Harvest Period

Volatile Organic Compounds (VOCs) over the harvest period have been assessed in twenty-five strawberry genotypes cultivated in western Greece. Using liquid–liquid extraction and gas chromatography–mass spectrometry (GC–-MS), twenty-eight volatiles were monitored at early (T1) and mid-harvest (T3) time points to investigate the effect of the genotype and harvest time on strawberry volatilome. A quantitative impact of both harvest date and genotype on VOCs associated with aroma was demonstrated, with the most significant VOCs being terpenes, esters, and acids, followed by lactones and furanones. Harvest date was crucial for terpenoid and phenylpropanoid content, and important for esters, short-chain acids, and lactones. Six out of the twenty-five genotypes (four commercial varieties, including ‘Rociera’, ‘Victory’, ‘Leyre’, and ‘Inspire’, and two advanced selection genotypes (G2 and G8) were evaluated at two additional time points, covering the entire harvest season. The volatile levels were higher in fruits harvested at early stages (T1–T2) for most of the genotypes examined. The G2 genotype turned out to have a less ample but more stable volatile profile throughout harvesting, while ‘Victory’, ‘Leyre’, and ‘Inspire’ exhibited less abrupt changes than ‘Rociera’. This study demonstrates that the determination of VOCs provides significant information regarding the differences in strawberry genotypes related to aroma and enables the selection of genotypes based on specific VOCs content and/or volatile stability over the harvest period. Furthermore, this study pinpoints that growers could opt for optimal harvest dates based on the genotypes and the VOC content

Conservation biology of threatened Mediterranean chasmophytes: The case of Asperula naufraga endemic to Zakynthos island (Ionian islands, Greece).

Asperula naufraga is a rare and threatened obligate chasmophyte, endemic to Zakynthos island (Ionian islands, Greece). In this study, we provide a combined approach (including monitoring of demographic and reproductive parameters and study of genetic diversity) to assess the current conservation status of the species and to estimate its future extinction risk. The five subpopulations of A. naufraga were monitored for five years (2014-2018). Population size markedly fluctuated between 68-130 mature individuals during the monitoring period. The extent of occurrence (EOO) was estimated at 28.7 km2 and the area of occupancy (AOO) was 8 km2. Stage-structure recordings were similar for all subpopulations, characterized by high proportions of adult and senescent individuals, following a common pattern, which has been observed in other cliff-dwelling plants. Preliminary genetic analysis with SSRs markers revealed low heterozygosity within subpopulations and significant departure from H-W equilibrium, which combined with small population size suggest increased threat of genetic diversity loss. Our results indicate that the species should be placed in the Critically Endangered (CR) IUCN threat category, while according to Population Viability Analysis results its extinction risk increases to 47.8% in the next 50 years. The small population size combined with large fluctuations in its size, low recruitment and low genetic diversity, indicate the need of undertaking effective in situ and ex situ conservation measures

Nutritional Value of Eggplant Cultivars and Association with Sequence Variation in Genes Coding for Major Phenolics

Eggplant is a widely consumed vegetable, with significant nutritional value and high antioxidant content, mainly due to its phenolic constituents. Our goal was to determine the levels of carbohydrates, proteins, total phenolics, anthocyanins, flavonoids, chlorogenic acid, and the antioxidant capacity in thirteen eggplant cultivars cultivated in Greece and to identify sequence polymorphisms in key regulating genes of the phenylpropanoid pathway (C4H, HCT, HQT, C3H, F3H, ANS, MYB1), which might relate to the phytochemical content of those cultivars. The carbohydrates’ content differs among and within cultivars, while the rest of the phytochemicals differ only among cultivars. The cultivars ‘EMI’ and ’Lagkada’ scored higher than the rest in phenolics, anthocyanins, ascorbic acid, caffeoylquinic acid, and antioxidant capacity. Moreover, significant correlations were observed between various ingredients and the antioxidant capacity (FRAP and DPPH). Sequence analysis revealed several SNPs in C4H, HQT, F3H, ANS, and MYB1 among the cultivars studied. According to chi-square and logistic regression analyses, the missense mutation C4H4-108 correlates significantly with flavonoids, anthocyanins, and proteins; the synonymous mutation HQT-105 correlates with anthocyanins and ascorbic acid; the missense mutation HQT-438 correlates with flavonoids and chlorogenic acid, while the missense mutation ANS1-65 correlates with anthocyanins and sugars. These polymorphisms can be potentially utilized as molecular markers in eggplant breeding, while our data also contribute to the study of eggplant’s secondary metabolism and antioxidant properties

Crop Landraces and Indigenous Varieties: A Valuable Source of Genes for Plant Breeding

Landraces and indigenous varieties comprise valuable sources of crop species diversity. Their utilization in plant breeding may lead to increased yield and enhanced quality traits, as well as resilience to various abiotic and biotic stresses. Recently, new approaches based on the rapid advancement of genomic technologies such as deciphering of pangenomes, multi-omics tools, marker-assisted selection (MAS), genome-wide association studies (GWAS), and CRISPR/Cas9 gene editing greatly facilitated the exploitation of landraces in modern plant breeding. In this paper, we present a comprehensive overview of the implementation of new genomic technologies and highlight their importance in pinpointing the genetic basis of desirable traits in landraces and indigenous varieties of annual, perennial herbaceous, and woody crop species cultivated in the Mediterranean region. The need for further employment of advanced -omic technologies to unravel the full potential of landraces and indigenous varieties underutilized genetic diversity is also indicated. Ultimately, the large amount of genomic data emerging from the investigation of landraces and indigenous varieties reveals their potential as a source of valuable genes and traits for breeding. The role of landraces and indigenous varieties in mitigating the ongoing risks posed by climate change in agriculture and food security is also highlighted