Effects Of Preservatives,Vase Solution PH And Cold Treatment On Postharvest Quality Of Cut Hydrangea Flowers

Hydrangea macrophylla is a kind of plant with high ornamental value,which is popular because of its large and beautiful flowers,various colors,beautiful posture,wide cultivars and long flowering period,and is often used in potted flower and landscaping.In recent years,it has been widely used in the production of cut flowers,and the demand for hydrangea is increasing year by year,and it is very popular all over the world.But its inflorescence is huge,its petals are soft,and it is easy to dehydrate after harvest,which leads to the wilting of cut flowers,reduces the ornamental value,and also affects the transportation and preservation after harvest.These problems not only affect the sales of cut hydrangea,but also restrict the development and further expansion of cut hydrangea market.In this study,cut hydrangea flowers were used as materials,and the postharvest preservation technology was discussed from the aspects of vase preservative,pH and storage.So as to delay the senescence of cut hydrangea flowers,improve the ornamental quality,prolong the vase life,and provide a theoretical basis for the preservation and storage of cut hydrangea flowers.The main conclusions are as follows:（1）Two Hydrangea cultivars（Hydrangea macrophylla’Classic Rood’and Hydrangea macrophylla’Glowing Alps’）were selected,which were harvested and placed in plastic cups filled with fresh-keeping solutions with different formulas to observe the quality after harvest.The results showed that the postharvest performance of H.’Classic Rood’cut flowers in different preservation solutions was better than that of H.’Glowing Alps’,in terms of vase life and ornamental evaluation grade after harvest.The treatment of 30 g/L S accelerated the senescence of cut flowers of two Hydrangea cultivars and shortened the vase life.For H.’Classic Rood’and H.’Glowing Alps’,the application concentration of salicylic acid（SA）was 0～20 mg/L and 0～15 mg/L respectively,which improved the vase life.Ca Cl₂concentration of 2 g/L was beneficial to the preservation of cut flowers of two Hydrangea cultivars and delayed the senescence of cut flowers.STS treatment caused two Hydrangea cultivars to wither quickly,which was toxic to hydrangea.STS was not suitable for vase solution of cut hydrangeas.For H.’Classic Rood’,the best preservative solution was 20 g/L S+200 mg/L 8-HQC+100 mg/L CA+15 mg/L SA and the vase life was 16days,while the best preservative solution for’H.’Glowing Alps’was 20 g/L S+200 mg/L8-HQC+100 mg/L CA+5 mg/L SA and the vase life was 11.33 days.（2）Effects of different vase solution pH on the preservation of cut flowers of H.’Classic Rood’were studied.The results showed that the vase life of cut hydrangea flowers increased first and then decreased with the increase of pH value of vase solution.When the pH was 4.0,the fresh-keeping effect of H.’Classic Rood’cut flowers was the best,which could effectively prolong the vase life,increase the maximum flower diameter by 3.32%,significantly slow down the change of fresh weight,maintain water balance,reduce MDA content,and slow down the increase of plasma membrane permeability.（3）The cut flowers of H.’Classic Rood’were stored in dry and distilled water at low temperature respectively.The cut hydrangea flowers were stored in distilled water,Chrysal and homemade preservative for short-term and long-term respectively.The results showed that the H.’Classic Rood’was stored in the refrigerator directly and withered within 24hours,so it was not suitable for the direct dry storage.Cut hydrangea flowers can be refrigerated for 28.67d days and 32.33d days in distilled water and Chrysal solution respectively,but the storage life in homemade preservative was only 3 days.The storage time of cut hydrangeas in distilled water and Chrysal should not exceed 4 weeks（28 days）and 3 weeks（21 days）respectively,otherwise the postharvest quality and vase life of cut hydrangeas will be reduced.In general,the cut H.’Classic Rood’is more suitable for cold storage in distilled water and Chrysal solution,but not in homemade preservative solution.