Abstract
Paulownia witches' broom (PaWB) caused by phytoplasma is a systemic disease which can be transmitted by insects. PaWB is the most destructive disease in Paulownia plantation in Taiwan. So far, no effective chemical is available for phytoplasma disease control. Therefore, ecological research of PaWB disease is necessary for providing information to develop a comprehensive prevention and control strategy. In this project specific and effective PCR primer of PaWB phytoplasma was designed and applied for PaWB detection, field research and resistant breeding. By tracking the Phytoplasma infection rate of various paulownia strains in different seasons, it can provide reference data to draft preventive strategies. 17 Paulownia plants in Taitung area were sampled monthly from February 2014 to June 2015 to evaluate the infection rate and variation of phytoplasma concentration in Paulownia plants. Totally 16 batches of samples were collected and PCR amplification with specific primers were carried out. PCR results indicated that the concentrations of phytoplasma in Paulownia plants varied seasonally. Population of insect vector of PaWB was monitored in Taitung sample area. Changshan erthesina fullo (Halyomorpha mista), a confirmed vector of PaWB, was not investigated in this area. However, a yellow-spotted stink bug, Erthesina fullo, was observed and suspected as another possible insect vector of PaWB.