Most commercial preservatives contain carbohydrates, fungicides, ethylene inhibitors, growth regulators and mineral nutrients. Their functions are summarized below.
Carbohydrate: It is the main nutrient source and energy source of cut flowers, and can maintain all physiological and biochemical processes of cut flowers after they leave the mother. Exogenous sugar sources will participate in prolonging the vase life and maintaining the structure and function of cut flower mitochondria. By regulating transpiration and cell infiltration, it can promote water balance and increase water absorption. Sucrose is one of the most widely used carbohydrates in preservatives, and fructose and glucose are sometimes used.
Different kinds of cut flowers or different varieties of the same kind are all suitable preservatives, and the sugar concentration is different. For example, the optimum concentration of carnation in bud-opening solution is 10%, while chrysanthemum leaves are sensitive to sugar, generally using 2%, and roses higher than 1.5% are easy to cause leaf burns. The optimum sugar concentration is also related to the treatment method and time. Generally speaking, for a specific cut flower, the longer the fresh-keeping treatment time, the lower the required sugar concentration, so the sugar concentration in pulse liquid (short time after harvest) is high, the sugar concentration in bud opening liquid is medium, and the sugar concentration in bottle holding liquid is low.
Bactericide: Bacteria, yeasts and molds are the kinds of microorganisms that grow in vases. When these microorganisms multiply in large numbers, they block the flower stem duct, affect the water absorption of cut flowers, produce toxic substances such as ethylene and accelerate the senescence of cut flowers. In order to control the growth of microorganisms, fungicides can be added to preservatives or mixed with other ingredients.
Ethylene inhibitor: Silver thiosulfate (STS) is the best ethylene inhibitor widely used in the flower industry at present, which has good mobility in plants and has an efficient inhibition effect on the ethylene synthesis of flowers. Effectively prolong the vase life of various flowers. STS needs to be prepared on demand. It is best to use the prepared solution immediately. If it is not used immediately, it should be stored at 2030℃ in the dark for 4 days.
Growth regulators: Growth regulators are used as flower preservatives, including synthetic auxin and plant endogenous hormones. Plant growth regulators can be used alone or mixed with other ingredients. It can cause or inhibit various physiological and biochemical processes in plants, thus delaying the senescence process of cut flowers. Cytokinin is the most commonly used one, which can mainly inhibit the production of ethylene. You can spray it or dip it when you apply it. The optimum concentration is 10 100ppm, and it can be soaked for 2 minutes. Too long time will also have adverse consequences, and carnation has the best therapeutic effect.
The above are the ingredients of flower preservative, but in actual production, the main ingredients of flower preservative are sugar and bactericide, and sometimes 12 ingredient is added. Because some cut flowers will secrete harmful substances from stem tips and submerged leaves, which will hurt themselves and other flowers in the same bottle, so the vase should be replaced with fresh ones every once in a while.