The Influence of Subculture Times on the Growth and Pyrethrins Mass Fraction of Pyrethrum [Tanacetum cinerariifolium(Trev. ) Sch. Bip]

For the study of subculture times on the growth and pyrethrins mass fraction of pyrethrum, we used high performance liquid chromatography(HPLC) method to determine the content changes of pyrethrins,and at the same time the growth vigor of pyrethrum plantlets in vitro was also analyzed. The results showed that with subculture for 5 times the content of pyrethrins increased first and then decreased,on the 3rd times of subculture reached the highest 1. 997 mg / g. Meanwhile,the times of sub-culture had impact on the vigor and roots growth of plantlets. The plantlets at the 3rdtimes of subculture were more vigorous with stronger roots than at the 1st times of subculture. At the 5th times of subculture,the plantlets showed slender foliage,slower growth phenomenon than other 4 times of subculture. Thus,the leaves of pyrethrins content of ‘F1-10-4'genotype had the strongest growth vigor at the 3rd times of subculture. Further subculture time did not improve leaves' pyrethrins contents and growth of pyrethrum and it could increase the cost.