Autotetraploid induction and identification of Rhodiola sachalinensis / 中草药

ABSTRACT

Objective: To obtain autotetraploid clones of Rhodiola sachalinensis. Methods: Germplasm with doubled chromosomes was acquired according to colchicine soaking seeds, and ploidy was identified according to stomata size and density measurements, chromosome counting and flow cytometry analysis. Chimera was purified after several times of regenerations. Results: Colchicine concentration and treatment duration had significant effect on seed germination rate, seedling death rate and ploidy mutation rates, and they were 18.2%, 73.6%, and 68.7%, respectively after the seeds were soaked in 0.2% colchicine solution for 72 h. Stomata diameter was promoted and density was declined significantly in morphological variation plantlets; normal diploid chromosome number was 2n = 2x = 26, and tetraploid chromosome number was 2n = 4x = 52. Meanwhile, aneuploidy was found in the population of plantlets after colchicine soaking, leaves of ploidy mutation plantlets were used as expiants to regenerate to tube plants, and homozygous clones were obained after three regeneration and purification cycles. There was no chimera in the homozygous clones according to flow cytometry analysis. Conclusion: It is feasible to obtain autotetraploid according to colchicine treatment on seeds of R. sachalinensis.