An attempt to assess susceptibility of young red and mature green leaves to cutting by Atta cephalotes

Abstract. Delayed greening is the delay of development of full photosynthetic capability in young leaves until after leaf expansion. Plants delay input of chlorophyll and photosynthetic enzymes to the developing leaf. It has been hypothesized that delayed greening is a response to high rates of herbivory on young leaves, and that it cuts losses incurred on the plant either by reducing investment in young leaves or by deterring herbivory on young leaves. I examined rates of cutting by the leaf-cutting ant Atta cephalotes of young red and mature green leaves of Inga ruiziana and Welfia georgii, two tree species that exhibit delayed greening. Little cutting occurred on any of the treatments, but all cutting was of young red leaves. Means of separating the two leading hypotheses on the causes of delayed greening are discussed. Delayed greening may deter herbivory or may reduce resource loss to ineveitably high herbivory. Each of these factors appears to be acting in some cases, and both may operate in the same plant species.