執行成果摘要
Paulownia Witches' broom (PaWB) disease is a systemic disease caused by phytoplasma and can be transmitted by insects. Paulownia plants are commonly infected in Taiwan. The infected ones become wilt within one year after infection, stop growing and eventually die at the end of second year of infection. PaWB could also be transmitted through vegetative reproduction between paulownia plants which makes fast spread of PaWB and limiting grow of paulownia. There is still lack of effective control for this disease so far, so that study of disease development is essential for paulownia health control. In this project, specific and effective PCR primer of PaWB phytoplasma has been designed and applied for PaWB detection, field research and resistant breeding. Paulownia fortunei and hybrids of P. fortunei and P.kawakamii showed higher resistance in resistance and intolerance test. Standard of performance was established for quantifying phytoplasma , field sampling and disease tracking were also executed in this project. Five spots, distributed in Kukeng (Yunlin county), Lianhuachi (Nantou county) and Taimali (Taitung County), have been set for tissue culture breeding test in field for continuous tracking infection rate, symptom observation and sampling. No obvious symptoms observed in these five regions, infection rate calculated by PCR detection showed 0% in both regions in Kukeng; 67% in Taimali; 0% in Lianhuachi-2; three different rate, 80%, 33% and 0% in Lianhuachi-1. Transmitted rate in vector insect, Halyomorpha mista, was 0% in Lianhuachi-1. Standard of procedure in phytoplasma quantification by PCR has been established in this project, and will be applied to resistance test and vector quantification analysis in the future.