Studies On Different Plant Growth Regulators In The Preservation And The Mechanism Of Cut Tulip

ABSTRACT Cut Tulip （Tulipa gesneriana ‘Princekin’） was used indifferent solutions, which added different concentrations plant growthregulators of PHDC, DA-6, DCPTA, BR, KT-30and TA into basicpreservative（200mg/L8-HQ+20g/L S）and6-BA was used as a controlregulator in this experiment. On the bases of floral appearance survey, effectsof PHDC、DA-6、DCPTA、BR、KT-30and TA on vase life and physiologicalaction of cut Tulip were investigated by means of measuring water balancevalue、change rate of the fresh weight, the content of soluble sugar, solubleprotein, free proline and MDA, the superoxide anion radical production rate,the activities of SOD and CAT. The main results were shown as follows:（1）As the vase life changed, the water balance value, change rate of thefresh weight were highest on the second or third day, then decreased. Thecontent of soluble sugar decreased at first, then increased, but decreasedultimately.The content of soluble protein at first increased but later decreased.The content of free proline increased slowly and gradually all the time. TheMDA and the superoxide anion radical production rate increased both,however the change rate of MDA was slower than O2-. The activity of SODand CAT increased, then decreased. The number of increase and decrease andthe time of turning point were different in different treatment, but they allcorrelated with the vase life. Although the trends of physiological andbiochemical indexes varied in different solutions containted plant growthregulators, but they were significant differences with the physiological andbiochemical indexes in distiiled water.（2）Compared with the distilled water and basic preservative treatment, the plant growth regulator PHDC, DA-6, DCPTA, BR, KT-30and TA all cansignificantly extend the vase life, improve its ornamental quality prolong thevase life, flower diameter, improve the water balance value, increase the freshweight, retarded the soluble sugar and the soluble protein, reduce theaccumulation of free proline and MDA, decrease the production rate of O2-,improve the activity of SOD and CAT, delay the aging of cut Tulip, raise freshdegree. The effect of200mg/L respectively PHDC,10mg/L DA-6,50mg/LDCPTA,1mg/L BR,50mg/L KT-30,1.5mg/L TA treatments were best. Thesix kinds of regulator treatment effects were also better than the bestconcentration of6-BA processing. Among them,50mg/L DCPTA is best, asthe vase life was12.77d, extended6.67d和4.60d respectively compared withCK-1and CK-2. The treatment of1.5mg/L TA takes the second place,extending the vase life6.37d and4.30d, separately compared with CK-1andCK-2. Again for50mg/L KT-30, its vase life was extended5.77d and3.70d,respectively compared with CK-1and CK-2.（3）According to the influences of different plant growth regulators onvase life, ornamental quality and the physiological indicators of cut Tulip, thisstudy selected three preservative solutions:50mg/L DCPTA+200mg/L8-HQ+20g/L S；1.5mg/L TA+200mg/L8-HQ+20g/L S；50mg/L KT-30+200mg/L8-HQ+20g/L S；1mg/L BR+200mg/L8-HQ+20g/L S；10mg/L DA-6+200mg/L8-HQ+20g/L S.