同根派生 Populus tremula相关词英汉例句Populus tremula L. [医] 山杨Populus tremula × P. tremuloides 欧美杂种山杨hybrid aspen( Populus tremula x P. tremuloides) 杂种山杨Study on tissue culture techniques of triploid Populus tremula 三倍体欧洲山杨组培技术的研究Populus tremula calli 欧洲山杨Populus tremula更多例句