The Laws of Branching and Trunk Extension Sprouted from Lateral Buds in Paulownia trees Study on the Temperature Characteristics of Dormancy Development of Terminal and Lateral Buds in Paulownia Analysis of Diploid and Its Autotetraploid Paulownia tomentosa×P. fortunei with AFLP and MSAP Growth of Paulownia Witches’Broom Seedlings Treated with Methylmethane Sulphonate and SSR Analysis