Study On Cultivar Selection And Postharvest Preservative Methods Of Cut-flowers In The Tree Peony

Tree peony is famous traditional flower in China.In recent years,the demand for tree peony cut-flower has been increased with the rapid development of chinese cut-flower market.However,the traditional tree peony cultivars?Paeonia suffruticosa?have a short flowering period and branches,and lack of systematic studying on postharvest storage and preservation technology.Therefore,it's significant to screen out the cultivars suitable for cut-flower production and make a profound study of the postharvest technology.Based on the specific target of cut flower production,this study screened out flare tree penoy cultivars which are suitable for cut-flower.Three flare tree penoy cultivars were used to explore the appropriate harvesting period,storage method and storage period.At the same time,we used orthogonal experiment to study the preservatives'responses of tree peony cut flowers to four chemical reagents?6-BA,SA,CA,Al₂?SO₄?₃?in basic vase preservative?Sucrose+8-HQ?and tried to find the best combination of preservatives.This study aimed at providing scientific evidence for postharvest technology of cut flowers.The results are as followed:1. We investigated 14 traits in 52 cultivars of tree peony?51 flare tree peony and P.×lemoinei‘High Noon'?and evaluate them by using grey relational grade analysis method.Through systematic cluster analysis of weighted relational grade,we recommend 18 flare tree peony cultivars and P.×lemoinei‘High Noon'as suitable cultivars for cut flower production,of which‘Jing Yu Hong',‘Fen Mian Tao Sai',‘Jing Fen Lan'and‘Jing Guan Hui Hong'were the most suitable to be used for cut-flower and popularized preferentially.2. The flower branches of two flowering stages?I and II?nomal bloomed in different cultivars?P.Rocii‘Jing Yun Guan',P.Rocii‘Gao Yuan Sheng Huo'and P.×lemoinei‘High Noon'?with high ornamental value.In practical production,the flower branches of two flowering stage can be directly harvested thus prolonging the harvesting time and improving the efficiency.3. The storage period of P.Rocii‘Jing Yun Guan'and P.Rocii‘Gao Yuan Sheng Huo'should be within twenty days and wet storage can significantly improve the optimum ornamental period compared with dry storage.As for P.×lemoinei‘High Noon',it's flower branches of stage I kept good ornamental value after 25 days storage by two storage methods,and it's flower branches of stage II also kept good value after wet storage.However,the ornamental value of stage II flower branches dereased a lot after20 days by dry storage of P.×lemoinei‘High Noon',it is suggested to choose wet storage to keep the ornamental value.The storage methods of stage I flower branches can be chosen according to the production conditions and stage II should choose wet storage.There may be longer storage period under of wet storage of P.×lemoinei‘High Noon'.4. The preservative can prolong the vase life of P.Rocii‘Jing Yun Guan'by 20%and the optimum ornamental period by 48.15%,and it was respectively prolonged by 33.33%and 68.89%of P.Rocii‘Gao Yuan Sheng Huo',and it was respectively prolonged by 24.53%and 40.54%of P.×lemoinei‘High Noon'.The preservative can improve the water balance,promote the water absorption and bloom,maintain the fresh weight and delay water balance value into negative of the flower branch,but the effect of the flower diameter increase varies with cultivars.The orthogonal experiment showed that the best combination of preservative was 3%S+200mg/L 8-HQ+0.5 mg/L 6-BA+50mg/L SA+200mg/L CA+50 mg/L Al₂?SO₄?₃of P.Rocii‘Jing Yun Guan',3%S+200mg/L 8-HQ+2mg/L 6-BA+50mg/L SA+100mg/L CA+200 mg/L AL₂?SO₄?₃of P.Rocii‘Gao Yuan Sheng Huo',3%S+200mg/L8-HQ+0.5mg/L 6-BA+50mg/L SA+100mg/L CA+50 mg/L Al₂?SO₄?₃of P.×lemoinei‘High Noon'.