Methods for conservation of intra-varietal genetic variability in ancient grapevine varieties

E Gonçalves,A Martins,P Roca

doi:10.1051/bioconf/20191501029

Abstract

Conservation of intra-varietal genetic variability is a crucial strategy to preserve traditional viticulture and to face future challenges. Conservation can be performed through two processes: (1) conservation without other immediate objectives; (2) conservation which simultaneously ensures the evaluation of important quantitative traits (such as yield, must quality traits, tolerance to abiotic stresses). The second strategy permits the quantification of intra-varietal genetic variability for important quantitative traits and the selection of a superior group of genotypes (polyclonal selection). Based on the results obtained from the conservation of ancient Portuguese varieties, the abovementioned methods for conservation of intra-varietal diversity are compared, and the advantages and disadvantages of each one are discussed.

Highlights

A very high level of genetic diversity was naturally created and accumulated over centuries within ancient varieties, but it has been exposed to a process of accelerated erosion since the mid of the twentieth century
As varieties are usually grown in several regions, samples with 400 or more genotypes are used. This strategy of conservation is currently conducted in Portugal by PORVID (Portuguese Association for Grapevine Diversity)
Conservation can be performed through two processes: (1) conservation without other immediate objectives; (2) conservation which simultaneously ensures the evaluation of important quantitative traits, including quantification of intra-varietal genetic variability for those traits, and selection of a superior group of genotypes

Summary

Introduction

A very high level of genetic diversity was naturally created and accumulated over centuries within ancient varieties, but it has been exposed to a process of accelerated erosion since the mid of the twentieth century. The conservation must contemplate representative samples of the diversity within all the autochthonous varieties. The sample size depends on the total growing area as well as on the number of discontinuous growing regions of the variety. Simulations studies found a minimum sample size per region with around 70 genotypes [1]. As varieties are usually grown in several regions, samples with 400 or more genotypes are used. This strategy of conservation is currently conducted in Portugal by PORVID (Portuguese Association for Grapevine Diversity)

Objectives

Methods

Conclusion