Leaf Folding in Mimosa Pudica (Fabaceae): A Nutrient Conservation Mechanism?

Abstract

Ten plants of Mimosa pudica L. were exposed to artificial rain following anesthesia of the leaves of half of the plants. Anesthetized plants, which no longer displayed the seismonastic response of this species, were hypothesized to show greater rates of foliar leaching of nutrients than their unanesthetized counterparts. Leachate was collected and analyzed for levels of K, Na and Ca. Levels were corrected for the amount of leaf area exposed to rainfall. No differences were noted between treatments for rainfall durations of either 6 or 20 min. Leaf surface morphology was examined and lattice‐like extrusions of epicuticular wax were found. We feel that the leaf surface structure may act to keep raindrops from coming in contact with the surface of the leaf thereby minimizing foliar leaching. It appears that the seismonastic response of the leaves plays only a minor role in nutrient conservation.

Applying Behavioral-Ecological Theory to Plant Defense: Light-Dependent Movement in Mimosa pudica Suggests a Trade-Off between Predation Risk and Energetic Reward

“…It has been suggested that the leaf folding behavior of M. pudica has benefits for the plant other than deterring herbivores. Wallace et al (1987) tested the hypothesis that leaf folding was a mechanism for reducing foliar nutrient loss in response to rainfall (one source of physical stimulation). By anesthetizing the plants, the researchers were able to prevent leaf closure, though they found no evidence of foliar nutrient leaching in either the experimental or the control plant groups.…”

An ecological perspective on water shedding from leaves

“…However, they did not provide any data to support this assertion. Active changes in leaf angle in response to drop impacts have only been shown for Mimosa pudica touch-me-not plants ( Applewhite, 1972 ; Wallace et al , 1987 ); however, the ecological relevance of this behaviour with regards to water shedding has not been investigated to date.…”