The hybrid tulip (Liriodendron Chinese ×L. tulipifera)trees grow quickly, the pole of which is big and straight, have a fast-growing characteristic, are the optimal roadside trees and the botanical garden trees. At present, the breeding and the cultivation of the hybrid tulip trees had the long history and had a big scale, specially the project team led by Nanjing forestry university Assistant Director Professor Shi Jisen had the new breakthrough in the breeding technology aspect recently, the seedling rest...