| It is one of important factors effecting on food security that pesticide residues in vegetable and fruit. So as to reduce chemical fungicide usage, many scholars start to find the new way to control postharvest diseases by safety and high efficiency botanical pesticides. This paper took Botrytis spp., Alternaria spp., Rhizopus spp., Phytophthora spp. for test materials and studied on antifungal activity of twenty-one Chinese Herbal Medicines alcoholic extracts by the method of mycelium growth and spore germination. Then mixed and extracted of the Chinese Herbal Medicines which had stronger antibacterial, the stronger antibacterial compound extracts were selected for vivo test. At last preliminary studied on the preservation effect on green pepper after treatment by compound extracts.1) It is showed that Syringa oblate, Schisandia chinensis, Alpinia officinarum, Asarum sieboldii Miq, Sophora flavesceus had strong inhibitory effect on mycelium growth, their inhibition rate were above 60% to more than three kinds of Pathogens of green pepper when their concentration was 0.02g/ml (Rhizopus spp. concentration was 0.005g/ml). Especially the inhibition rate of Syringa oblate was 100%to four kinds of Pathogens. Fructus Mume, Syringa oblate, Schisandia chinensis also showed strong inhibitory effect on spore germination of Alternaria spp. and Botrytis spp. when their concentration was 0.01g/ml, their inhibition rate above 70%.2) This paper studied on the extracting of Syringa oblate in different extractions concentrations. The results showed that the optimum technological condition was 95% ethanol extraction.3) This paper also studied the effect of solvent concentrations on inhibition rate, the results show that 0.008g/ml was a turning point concentration, concentration was a good linear relation with inhibition rate in the range of 0.001-0.008 g/ml.4) For the search of compound extracts, based on the above results, we conducted the comprehensive experiment using Syringa oblate, Alpinia officinarum, and so on, the results showed that Syringa oblate and Schisandia chinensis, Alpinia officinarum, compound extracts have a strong inhibition when their Concentration was 0.005g/ml, there inhibition rate eceeded 70% to more than three kinds of Pathogens of green pepper. And there were significant differences between the compound extracts of Syringa oblate and Fructus Mume to inhibiting Alternaria spp., the compound extracts of Syringa oblate and Alpinia officinarum to inhibiting Botrytis spp. and others.5) Inoculation test showed that there was a good protective effect when the green pepper was soaked in 0.005g/ml compound extracts of Syringa oblate and Alpinia officinarum, Syringa oblate and Alpinia officinarum for 3 min,and there was a good therapeutic effects when spray with compound extractions as the same concentration of Syringa oblate and Alpinia officinarum, Syringa oblate and Fructus Mume.6) The physical and chemical characters of DWUG and Syringa oblate extraction were tested after being treated at different temperature, illumination and the activity maintenance. The results showed that DWUG has better effects than Syringa oblate extraction after temperature treatment, but the inhibitory activity of DWUG also decreased sharply when temperature higher 60℃or lower -4℃. After treated with illumination, both of them had no significant change in the inhibitory activities. The stability of DWUG was better than Syringa oblate extractive.7) DWUG was applied to pepper fresh-keeping, the results showed that DWUG had really significant fresh-keeping effects. Compared to check treatment, DWUG treatment can reduced respiratory intensity, keet Vc content, decreased rot rate and prolonged the period of storage. But, the index of changing red increased and chlorophyll content reduced, and the reason needs a further research. At the same time studied on the effect of green pepper fresh-keeping with the complex coating agents containing 50g DWUG and 10g chitosan in one litre. The preservative experiment results showed that, compared to DWUG and check treatment, the complex coating could inhibit decomposition of chlorophyll, evidently reduce respiratory intensity.
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