Study Of The Sprouting Inhibition Of Exogenous Ethylene For Potatoes And Its Mechanism

Potato is the second plant followed by food industry in our plant field. Itssprouting and greening will bring heavy lost for businessmen and productors andendengrous for consumers. In this paper, we treated the potatoe s by solid ethylenerelease agent, then studied the regulation of exogenous ethylene for the potatoes’sprouting. To study its sprouting inhibition mechanism, the effection of exogenousethylene on carbonhydrate, phenol, phytohormone, embran and related enzyme weremeasured here. The result indicated that is as follow:1.Exogenous ethylene reduced the potato sprouting process，however，sproutingcouldn’t be suppressed completely. The higher the concentration of ethylene，thebetter the inhibition effect was. The effection were better in potatoes treatedrepeatedly or solid ethylene releasing agents dipped in water. Moreover, the inhibitionwas more evident when potatoes were treated at lower tempreture.2. During the storage, exogenous ethylene decreased the decline rate ofrespiration slightly, elevated the increasing of total sugar and decreased the decline oftotal educing sugar. Neverthless, glucose and fructose varied minimally. The declinerate of sucrose was increased significantly by exogenous ethylene and relatedpositively with its amount. The effect on starch were different based on its amount.Among them, the larger relation with sprouting indexes were exsited in the changes oftotal sugar, total reducing sugar and sucrose content.3. The obvious effection could be found in phenols. For example, theaccumulation of total phenol and flavonoids were suppressed, and for total phenol theclearer effection present in the treatment of lower amount of exogenous ethylene, theresult was contrary in total flavonoids. However, Anthocyanin content was decreasedby exogenous ethylene, especially in the treatment of higher amount of exogenousethylene. Among phenolic components, the more obvious effection present in caffeicacid, vanillic acid and quercetin.4. Exogenous ethylene could elevate the level of some endohormones, such asgibberellic acid, salicylic acid, auxin, zeatin and jasmonic acid. While the degreeswere nearly related with its amount. Additionly, low dose of exogenous ethylenecould enhance abscisic acid content, but its role was opposite in other treatments. Theexperimental results of the balance among hormones manifested that the most significant effection could be found in gibberellic acid. In a word, potatoes with lowersprouting indexes had higher content of gibberellic acid, salicylic acid, auxin, zeatinand jasmonic acid.5. After treated by exogenous ethylene, the potatoes had lower level ofmalondialdehyde, and higher content of L-proline and reducing glutathione. Itseffection on ascorbic acid varied with the dose of exogenous ethylene, as well aselectrical conductivity. Among different treatments, potatoes with the lowestsprouting indexe tended to appeared lower levels of malondialdehyde and electricalconductivity, higher content of L-proline, reducing glutathione and ascorbic acid.6. During storage period, exogenous ethylene could reduce the total proteincontent, and enhance the activity of superoxide dismutase, polyphenol oxidase,catalase, phenylalanine ammonia-lyase. The effection on peroxidase and scorbateperoxidase were also obvious, but changed with its amount. So, several parametersmeight be beneficial to potatoes storage, for example, lower level of protein, higheractivity of superoxide dismutase, polyphenol oxidase, catalase, phenylalanineammonia-lyase.