Armenia: historical origin of domesticated grapevines

Abstract

The Armenian highlands are located on the northern border of western asia and stretch up to the caucasus from the north. Throughout human history, country has played an important role in connecting the civilizations of europe and the near east. The recent large-scale study about the dual domestication origin and evolution of grapes approved that in the Armenian highlands human and grapevine stories are interlaced through centuries and roots of grapevine domestication are found deep in the pleistocene, ending 11.5 thousand years ago. Findings of this study confirmed that glacial episodes distinguish wild grapes into eastern and western ecotypes around 200-400 ka. During the last glacial period, the eastern ecotype split into two groups. Each group underwent separate domestication processes in the near east and south caucasus. The limited migration from Armenia safeguarded exceptional diversity and uniqueness of grapevine genetic resources. Since ancient times, grape has had religious and cultural importance for the Armenians. In the works of Armenian historians and epigraphic inscriptions, there are several references to vineyards, wine presses and wine. The Armenian church played a key role in the growth of viticulture and wine-making as important economic sectors. Almost all monasteries and renowned churches had vineyards and wine presses and wine had an essential role in religious and spiritual life. In recent decade, the wine industry in Armenia has undergone a renaissance, but only a limited number of autochthonous grapes have been used for wine production. This fact led to a serious shift towards single-variety vineyards decreasing genetic diversity, as only 30-35 of the 450 native grapevine varieties are used for wine and brandy production. Numerous minor autochthonous varieties having locally importance were underutilized due to a lack of precise characterization and missing data on oenological potential and agronomical traits. All these arguments confirmed the significance and urgency of the collection, conservation, characterization, and efficient utilization of grape germplasm resources, along with knowledge of the genetic and genomic diversity.  Until recently very little was known about the real magnitude of grape germplasm in Armenia. To address the gap in 2017, a nationwide program was launched to collect, conserve, and thoroughly characterize Armenian grapevine germplasm. Then, in 2018, an extensive and groundbreaking study was conducted and illumina paired-end sequencing was used to analyze nearly 175 indigenous and wild grapes. The objectives of research during last ten years were: i) recovery and conservation of Armenian grape diversity ii) accurate determination of the grapevines identity iii) assessment of the level of genetic diversity; and iv) investigation of genetic relatedness of Armenian grape germplasm. Obtained results indicated that high genetic and morphological diversity as a source of novel alleles and genotypes is still safeguard in Armenia. A combination of genomic data, nuclear microsatellite markers and ampelography proved useful to determine the identity of collected samples recovered from old vineyards and home gardens, to analyze genetic relationships among two subspecies of vitis vinifera, to demonstrated existence of gene flow between the wild and cultivated grapevines through overlaps and presence of admixed ancestry values. The grape currently faces drastic pathogen pressures, and the long-term sustainability of the vine and wine sectors will depend on the exploitation of the immense natural genetic diversity of grapes. V. Sylvestris germplasm in Armenia has shown huge potential to contribute to the development of improved cultivars with enhanced disease resistance, adaptability, and quality traits. Armenian grape gene pool richness represents a tremendous reservoir of under-explored genetic diversity and breeding potential.