Is there a genetic basis for fluctuating asymmetry and does it predict fitness in the plant Lotus corniculatus grown in different environmental conditions?

Fluctuating asymmetry (FA) is considered to be a good measure of developmental stability. We measured the asymmetry of leaves and flowers of 16 different genotypes of Lotus corniculatus grown in four different experimental environments to estimate the plasticity or developmental stability of asymmetry itself. We found that an index of FA (absolute difference between size of left and right sides, corrected for trait size) differed significantly across environments, with the treatment CO2+/N+ inducing the greatest FA for both flowers and leaves. Genotypes did not differ in FAs. Individual plants showed significantly different FAs only for flowers. At the individual level, we found no significant relationship between flower FA and fitness. Previous work indicates that change in asymmetry in a poor or perturbing environment Versus a good environment could reflect the intrinsic quality of a particular genotype. However, in our experiment, genotype effect was significant only for change in asymmetry of leaves, and this last trait was not significantly correlated with our fitness estimate for each genotype in either the most or the least perturbing environment.