Associations between the α-terpineol synthase gene and α-terpineol content in different grapevine varieties

<p>α-Terpineol is one of the main monoterpenes found in the grape berry (<i>Vitis vinifera</i> L.) with its concentrations varying in different varieties. The present study was conducted to identify associations between the α-terpineol synthase (<i>α-TPS</i>) gene, a regulator of α-terpineol metabolism, and α-terpineol content in different grapevine varieties. We used a core collection of 61 grape accessions to identify causal single nucleotide polymorphisms in <i>α-TPS</i>, and evaluated the α-terpineol content in two consecutive years (2014 and 2015). Twenty SNPs were detected in the <i>α-TPS</i> coding region and were used in an association analysis. We found that the α-terpineol levels were higher in the varieties with a T/G genotype at S133 than in the varieties with other genotypes at this site. Additionally, we found S1556 (C/T) with a functional effect on α-terpineol content related to the regulation of gene transcription. This study suggests a relationship between <i>α-TPS</i> and α-terpineol content, with the identified polymorphism sites potentially assisting in the molecular breeding of grapevines.</p