Female catkins were treated with 0.2%-0.6% colchicine solution during 12-48hrs pollination in cross combinations between dialing poplar×weihe poplar, Some hybrids were obtained by treating the pollinated flowers with colchicine solution and without solution colchicines. Then the hybrids by treating the pollinated flowers without colchicine were treated with 0.1%-0.4% colchicine solution. After finishing the above process, sow all seed at the same time. Water and nutrients were managed during the whole growt...