【摘要】 采用核型分析和巢式方差等级分析等技术对分布于海南的海南粗榧5个种群染色体水平遗传多样性进行了研究,结果表明:1)坝王岭种群、尖峰岭种群、卡法岭种群、黎母岭种群和吊罗山种群核型公式分别为:2n=2x=24=16m+6msm+2sm(2SAT)、2n=2x=24=16m+6msm+2sm(2SAT)、2n=2x=24=18m+4msm+2sm(2SAT)、2n=2x+24=20m+2msm+2sm(2SAT)和2n=2x=24=18m+4msm+2sm;2)相对长度变异最高的为第5对染色体(90.35%),最低的为第10对染色体(24.54%);臂比变异最高的为第4对染色体(86.54%),变异最低的为第12对染色体(40.228%);3)虽然海南粗榧不同种群核型表现出一定差异,但是其间差异不显著,都为较原始的2A型;4)无论是相对长度还是臂比,种群内的变异量总是远远超过种群间的变异量;其中坝王岭种群和吊罗山种群间的变异其相对长度和臂比都是最高的,坝王岭和卡法岭种群、卡法岭和吊罗山种群的变异最低;5个地点海南粗榧种群间的VST值平均为10%,即在常规染色体的遗传变异中,平均只有10%的变异来自于种群间,而大部分变异(约90%)来自于种群内的个体和细胞间.这样的分化系数表明在海南粗榧种群间进行着频繁的基因交换.更多还原

【Abstract】 Based on karyotype analysis and nested analysis of variance, the karyotype and its variation of different Cephalotaxus mannii Hook.f. population were studied. The research shows that: (1)the karyotype formulas of populations in Mt.Bawang, Mt.Jianfeng, Mt.Kafa, Mt.Limu and Mt.Diaoluo are respectively 2n=2x=24= 16m +6msm +2sm(2SAT)、2n=2x=24=16m+6msm+2sm(2SAT)、2n=2x=24= 18m +4msm+2sm(2SAT)、2n=2x+24=20m+2msm+2sm(2SAT)and 2n=2x=24= 18m + 4msm+2sm;(2) the fifth chromosome expresses the most variance(90.35%) of ratio of chromosome and the tenth chromosome the least(24.54%); the fourth chromosome expresses the most variance (86.54%) of arm ratio and the twelfth chromosome the least(40.228%); (3) the difference in karyotype of Cephalotaxus mannii Hook.f. populations is not notable, the karyotype is 2A type; (4)the major difference of genetic diversity in karyotype variances dispersed within population(90%), and among populations(10%). This shows that a strong gene flow exists between populations.更多还原