木薯根尖染色体制片方法的优化

Optimization of Chromosome Spreading Technique in Cassava Root Tip Cells

以华南6号木薯根尖为材料,采用酶解去壁低渗法和压片法,制备木薯染色体标本,并对其制片过程中的预处理药品、预处理时间、酶解时间等因子进行优化。结果表明:酶解去壁低渗法能获得较好的染色体标本,α-溴代萘与对二氯苯饱和液的混合液和0.1%的秋水仙素与0.002 mol/L 8-羟基喹啉混合液的预处理效果最好,预处理时间以2 h为宜,酶解时间4 h效果最好。

Chromosome spreading technique is of great significance for chromosome and karyotype ploidy breeding, interspecific hybridization and germplasm analysis of cassava. Chromosome spreading of root tip cells of cassava （cult. Huanan 6）was performed using squash and enzyme digestion, low osmotic method, respectively. Some important factors during the preparation, such as chemicals and time for pretreatment, enzymolysis time, were discussed to optimize the chromosome preparation. Our results showed that the enzyme digestion, low osmotic method was the best one for chromosome preparation of the cassava root tip cells. The optimum pretreatment chemical was the mixture of the α-bromonaphthalene with saturated solution of p-dichlorobenzene and the mixture of the 0.1% colchicine with 0.002 mol/L 8-hydroxyquinoline（ 1：1 ）, and the pretreatment time 2 hours, enzymolysis lasted 4 h at 37 ℃.