Effect of Three Growth Regulators on Pyrethrin Content and the Traits Related to Pyrethrin Yield
Pyrethrin content and the traits related to pyrethrin yield were determined after the application of ethrel,paclobutrazol and daminozide using a good pyrethrum clone selected from field in Yunnan Province. The results showed that three growth regulators significantly increased the pyrethrin content in flower, and both of 1 000 mg/L daminozide and 50 mg/L ethrel were better treatments, with a growth rate of 17.9% and 15.2%, respectively.Ethrel, paclobutrazol and daminozide also increased the pyrethrin yield by improving the fresh and dry flower yield, and paclobutrazol at 150 mg/L gained the highest pyrethrin yield with 770 mg/plant higher than the control,following with 50 mg/L ethrel treatment which was 514 mg/plant higher than the control.