| In this paper, the fresh-keeping and antifungal effectiveness of 90 essential oils on postharvest fruits were conducted at room temperature. Firstly, the fresh-keeping activity of tested essential oils on postharvest apricot and kiwifruits was researched by the fumigation method. And we studied the inhibitory effects against mycelia growth of Penicillium italicum of 90 essential oils. Then the control effects in vivo and the antiseptic effects of cinnamaldehyde on postharvest fruits were researched. The primary conclusions were as follows:(1) Tested essential oils have no obvious fresh-keeping effect on postharvest apricot and kiwifruits at room temperature.(2) 11 essential oils had better inhibitory effects against mycelia growth of Penicillium italicum than other oils. They were star anise oil, thyme oil, clove basil oil, clove leaf oil, lemon grass oil, citral, cinnamon oil, cinnamaldehyde , litsea essential oil, geraniol and laurel leaf oil. Clove leaf oil has the highest contact phase effect and its EC50 is 149.24μl·L-1. Thyme oil has the highest volatile phase effect and its EC50 is 25.69μl·L-1.These 11 essential oils also have inhibitory effects against mycelia growth of Penicillium digitatum, Botrytis cinerea, Trichothecium roseum, Colletotrichum gloeosporioides and Diaporthe medusaea (Nitsehke), especially to the Botrytis cinerea.(3) Volatile phase effects of tested essential oils is significantly higher than their contact phase effects. The EC50 of volatile phase effect of thyme oil is 25.69μl·L-1, and its EC50 of contact phase effect is 234.81μl·L-1.(4) The result in vivo showed that their therapeutic effects against Penicillium italicum is significantly higher than protective effects. Cinnamaldehyde has the highest control effect against the Penicillium italicum on orange. At the concentration of 1000μl·L-1, its therapeutic effect against Penicillium italicum on orange by means of soaking method is 59.14% and its protective effect is 20.01%.(5) The control effects in vivo showed that the preservative effects of cinnamaldehyde against against Penicillium italicum on roange is good by means of soaking or fumigation. The longer soaking time, the better therapeutic effect and protective effect. When soaking time is 10, 20 and 30 minutes at the concentration of 2000μl·L-1, their protective effects are 34.26%, 43.83% and 56.17% respectively. When soaking time is 3, 5 and 7 minutes at the same concentration, their therapeutic effects are 61.70%, 83.59% and 95.04% respectively. Fruit can be injured if the soaking time is longer than 11 minutes. The control effect of fumigation is better than that of soaking. At the concentration of 35μl·L-1 and 50μl·L-1, control effects are 79.45% and 91.91% respectively. Fruit can be injured if the fumigation concentration is higher than 40μl·L-1.(6) The result in postharvest storage showed that the effects of inhibiting fungal decay on citrus fruits and strawberries are not significant when fruits are soaked by the liquid of cinnamaldehyde alone. But the preservative effects is significant good by fumigation. When citrus fruits were soaked by the liquid of cinnamaldehyde at the concentration of 2000μl·L-1, the rate of sound fruit is 43.06% after 40 days while the CK is 38.74%. soaked by the liquid of cinnamaldehyde at the concentration of 1000μl·L-1 and 500μl·L-1 separately, the rates of sound fruit of strawberry are 32.46% and 31.90% separately while the CK is 22.38%.(7) The result in postharvest storage showed that the effects of the cinnamaldehyde treatments in combination with chitosan were better than that of cinnamaldehyde treatments alone. When citrus fruits were treated in combination with cinnamaldehyde, chitosan and propamidine, the rate of sound fruit is 73.08% while the CK is 38.74%. When strawberry wre treated in combination with cinnamaldehyde and chitosan, the rate of sound fruit is 55.74% while the CK is 22.38%.Cinnamaldehyde is low toxic, safe, cheap and ordorus. Being a safe material, it can be used for natural preservative in fruit and vegetable storage.
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