Genotypic and environmental effects on the compounds associated with garlic flavor, health-enhancing properties, and postharvest conservation

Abstract

To estimate genetic and environmental effects on traits associated with garlic (Allium sativum L.) functional value and postharvest quality, the content of total organosulfur compounds, phenolics, and solids were determined in selected garlic cultivars grown at four locations in Mendoza, Argentina. An initial experiment considered five cultivars grown in two locations and 2 yr, and a second experiment evaluated 12 cultivars across four locations. Among all the cultivars and locations, pyruvate levels, an estimator of total organosulfur content, varied more than fourfold (with a range of 24.7–111.1 μmol/g fresh weight), phenolics varied ∼fivefold (132.1–703.1 mg gallic acid equivalents/kg fresh weight), and solids varied within a range of 28.4 to 41.2%. Strong environmental influence and genotype × environment interactions were found for all traits, together accounting for 54.8 to 63.2% of the variation found for pyruvate, 63.3 to 81% for phenolics, and 35.1 to 50.8% for solids. The impact of genotype was higher for solids (31.9–50.9% of total variation) than for pyruvate (33.6–40.4%) and phenolics (16.1–34.1%). Despite the substantial environmental influence and genotype × environment interaction found, individual garlic cultivars with consistently high levels for all of these compounds were identified. We conclude that garlic pyruvate, phenolic, and solids levels are genetically and environmentally conditioned. The identified genotypes with consistently high phytochemicals content are valuable to breeders aiming at increasing garlic flavor, functional value, and postharvest quality, whereas locations yielding contrastingly high or low pyruvate levels are of interest for producing pungent and mild garlics, respectively.