Leaf Fluctuating Asymmetry and Herbivory of Tibouchina heteromalla in Restored and Natural Environments

Abstract

Fluctuating asymmetry (FA) is a parameter to measure developmental stability in plants, which can be altered by disturbances, pollution, and biotic factors such as herbivory. We evaluated the effects of environmental stress and herbivory on the FA levels in individuals of Tibouchina heteromalla (Melastomataceae) that occur in natural and undergoing restoration areas in rupestrian grasslands at Serra do Cipó, Brasil. Individuals were collected and measured in seven restored and five natural areas, totalizing 240 individuals. We found that individuals in restored areas had greater leaf area, higher levels of insect herbivory and FA compared to individuals that occurred in natural areas. In both environments, the proportion of individuals with leaf damage caused by herbivory was higher than the proportion of undamaged individuals. In addition, FA was positively correlated with herbivory and total leaf area in both restored and natural areas. These results suggest that more favorable conditions in the restored areas enhanced leaf growth, resulting in higher FA.

Local Insect Damage Reduces Fluctuating Asymmetry in Next-year’s Leaves of Downy Birch

“…Many researchers have explored correlations between average levels of leaf FA (based on 10–20 leaves per plant) and different indices of insect herbivory. These observational studies did not reach an agreed conclusion; some of them reported higher herbivory on plants with higher FA [ 5 , 6 , 7 ], while others discovered the opposite pattern [ 8 ], or reported the absence of any correlation between plant FA and herbivory [ 9 , 10 , 11 ].…”