同源四倍体芦荟的诱导研究

Studies on Induction of Autotetraploid of Aloe vera L.

取库拉索芦荟 ( Aloe vera L .)的茎段、叶片作外植体接种于 MS附加不同激素的培养基上 ,诱导出丛生芽、微块茎、愈伤组织 ,将丛生芽、微块茎、愈伤组织分别用浓度为 0 .0 1% ,0 .0 2 % ,0 .0 5 %的秋水仙素以不同的方法和时间处理 ,丛生芽和微块茎能较好地诱出变异体 ,其中以 0 .0 2 %的秋水仙素棉球覆盖处理丛生芽 4 8h诱变效果最好 .变异体叶片肥厚、根粗壮 .筛选稳定的变异体继代 ,经染色体数目观察 ,二倍体植株染色体数目为 2 n=2×x=14 ,x=7,不同变异体染色体数目不同 ,其中 80 %以上的变异体细胞染色体数 2 n=4×x=2 8,x=7,为同源四倍体 .四倍体气孔器明显大于二倍体 .四倍体试管苗在 MS+ BA4 mg/l NAA0 .2 mg/l可以大量增殖 ,并于 1/2 MS+NAA0 .3mg/l IAA0 .3mg/l培养基上诱大量根 .试管苗移栽成活率达 90 %以上 .

The stem segments and leaves of Aloe vera L. were cultured on MS medium with different hormones. The calli,microtubers and clumpy buds were induced, they were treated by various colchicine concentration of 0.01%,0.02%,0.05% during different time by diverse measures, the result indicated that the induced ratio of various plantlets from clumpy buds are the highest when those buds are covered with cotton during 48 hours treated by colchicine concentration of 0.02%.The stable variations were selected to keep on propagating, lots of new buds formed when cultured on MS+BA 4mg/l NAA 0.2mg/l . They could also yield roots on the 1/2MS medium with NAA 0.3mg/l IAA 0.3mg/l . Compared with the diploids, the appearance of variations is distinct including plumper leaves, larger gas guard cells and stronger roots. The chromosome numbers of diploid are 14 (2 n=2×x=14,x =7) while autotetraploids' are 28(2 n=4×x=28,x =7).When they were explanted in soil with sand,all most 80 percent of them kept alive.