Genetic differences in macro-element mineral concentrations among 52 historically important tomato varieties

Tomato ( Solanum lycopersicum ) fruit quality and yield are highly dependent on adequate uptake of nutrients. Potassium, magnesium and calcium are essential elements that influence fruit quality traits such as colour, uniformity of ripening, hollow fruit, fruit shape, firmness and acidity. Sodium is not an essential element for tomato and can detrimentally compete with the absorption of potassium and calcium. Daily intakes of potassium, magnesium and calcium in human diets are typically below healthful levels, while sodium intake is often excessive. The objective of this study was to compare 52 diverse commercially important varieties of tomato for concentrations of potassium, magnesium, calcium and sodium in fruits. The tomatoes were produced in replicated plots in Geneva, NY in 2010 and 2011. Multiple fruits per plot were harvested vine-ripe, homogenized and assayed for cations. Analysis of variance showed significant differences among the 52 varieties for all four traits, i.e. cation concentrations (df = 51, P P = 0.3432–0.6770). Factor analysis showed a strong interrelationship between potassium and magnesium that was independent of calcium and sodium. Potassium and magnesium were highly significantly correlated with each other ( r = 0.64, P