Effect Of Nitric Oxide (NO) On Storage Ability And Active Oxygen Metabolism Of Postharvest Strawberry

In this thesis, the effect of postharvest treatment with NO on respiration rate, the rate of ethylene production, relative membrane permeatility, firmness, loss of weight, anthocyanin content, chlorophyll content, titritable acide content, soluble sugar content, Vc content, MDA content, TSS, soluble protein content and the active oxygen metabolism and the enzyme activities correlated with active oxygen metabolism. of "hongtaihou"strawberry fruit after postharvest. The relationship of nitric oxide and strawberry senescence, the physiological and biochemical mechanism of ripening and senescence were also discussed. All above provided theoretical bases for NO applying to fruits storage. The results of study showed that: (1) Exogenous NO could delay the loss of firmness, restrain the decomposition of chlorophyll and synthesis of anthocyanin, decrease fruit weight,rotting tate, retard the decrease of contents of protein, Vc, titritable acid, and change of soluble sugar, TSS content, decrease MDA content and membrane permeability. So NO could maintain fresh-keeping and delay senescence. It indicate that the exogenous nitric oxide has good keeping fresh action . antistaling for strawberry. And nitric oxide will become an ideal agent. (2)NO could inhibit partly the increase content of H₂O₂,O₂^-. and the enzyme activities relating to active oxygen metabolism :SOD, CAT, POD, APX. (3)NO could reduce the rate of respiration and ethylene production of strawberry during storage. (4)NO restrained the loss of fruit firmness, the increase of respiration rate, ethylene production rate, the change of fruit colour, and prevented the increase of active oxygen (H₂O₂, O₂^-.) and the enzyme activities relating to active oxygen metabolism in certain degree induced by exogenous ethylene.