Root tips fixed by 95% ethonal were digested with an enzyme mixture ofcellulase and pectolyase, then used to prepare chromosome samples. The targetchromosome was microdissected by using a hand-made microglass needle under aninverted microscope.

• 取95%25乙醇固定后经果胶酶和纤维酶酶解的根尖制备染色体标本，用自制的微细玻璃针在倒置显微镜下挑取目的染色体。