Abstract
The maize orange leafhopper Cicadulina bipunctata is a serious pest of second crops of forage maize in Kyushu, Japan. The insect induces galls on various plants of Poaceae, which are characterized by stunted growth and severe swelling of leaf veins. Previous studies indicate that some chemicals injected by the insect affect the shoot apical meristem and induce galls on the leaves that have extended during the feeding. To clarify the mechanism underlying the gall induction, we performed high-throughput and comprehensive plant hormone analyses by LC-ESI-MS/MS, in leaves infested and galled by C. bipunctata. As a result, galled rice leaves contained higher and lower contents abscisic acid (ABA) and salicylic acid (SA) than ungalled leaves, respectively. Galled maize leaves had much more contents of ABA, especially around shoot apical meristems than ungalled leaves. We discuss possible gall-inducing processes by C. bipunctata.
