Developmental Potential of Galls Induced by <i>Diplolepis rosaefolii</i> (Hymenoptera: Cynipidae) on the Leaves of <i>Rosa virginiana</i> and the Influence of <i>Periclistus</i> Species on the <i>Diplolepis rosaefolii</i> Galls

Abstract

The larval stages of the cynipid wasp Diplolepis rosaefolii induce the formation of single‐chambered, lenticular galls on the leaves of the wild shrub rose, Rosa virginiana. The development of galls induced by D. rosaefolii was studied using light and scanning electron microscopy. The gall consists of four tissue layers, which surround a centrally located larval chamber. These include an outermost dermal layer, underlying parenchyma, sclerenchyma, and nutritive tissue. Development in the D. rosaefolii galls involves a number of characteristics that are unique to this gall and differ markedly from development in other Diplolepis galls studied. These characteristics include the presence of double sclerenchymal layers and vascularization embedded between the sclerenchyma. Periclistus is an inquiline in the galls induced by D. rosaefolii. Under the influence of Periclistus larvae, a number of morphological changes, including an increase in the number of larval chambers, are observed in the galls. Changes in tissue type, proportion, and overall morphology exhibited by Periclistus‐modified galls are also studied using conventional light microscopy techniques.