Genetic Variation in Floral Traits of Echium vulgare

Abstract

We estimated the genetic basis for variation in floral traits and the phenotypic and genetic correlations between these traits using clonal propagation in Echium vulgare (Boraginaceae). For all floral traits measured (nectar volume, nectar sugar concentration, sugar production, corolla size, style length, stamen length) we found significant clonal repeatabilities in a greenhouse experiment. Variation among clonal families in nectar volume was surprisingly high (seven-fold difference between the highest and lowest family mean) and not correlated with flower size. Variation among clonal families in pollen production was even higher (28-fold) and correlated to flower size traits. Corolla length, style length and stamen length were all highly correlated. Flower size is not a good predictor for nectar production rate, while it is for the number of pollen grains produced.