| Used Botrytis cinerea for the tested bacteria, made use of the technique of electron beam irradiated to the conidia, hyphae of Botrytis ,and fresh strawberries,respectively. Used agar surface germination method and digital microscope observated the activity of radiation on conidial germination and morphology; through the induction medium and shaking culture,tested cell wall degrading enzyme activities of the different radiation dose on B. cinerea. Discussed irradiation on the antibacterial activity of tested strains and related mechanisms preliminary. used living organisms studied the virulence of B. cinerea and the consequences of strawberry enzyme activity after irradiated. The results are as follows:1.Used B.cinerea conidia as the research objective, measured the effects of irradiation on B. cinerea spore germination activity and pathogenicity under 0℃, 5℃, 10℃, 15℃, 20℃, 25℃culture temperatures after irradiated by 0.5,1.0,2.0 and 3.0 kGy dosage. The results showed that: Electron beam treatment could inhibited the B. cinerea spore germination, germ tube elongation and hyphae formation, delayed the time of conidia reached full germination significantly, reduced its pathogenicity, and the higher dose , the more obviously effects. 1.0 kGy or more treatment could inhibited the B. cinerea spore germination activity obviously, slowed down spores reached to completed germination time; and the lower the temperature the more significant effects. Compared with the control group, under different culture temperatures, 1.0 kGy or more electron beam treatment could inhibited the germination of spores all significantly. At 5℃temperature culture, spore germination activity was decreased obviously, total germination time was longer, conidia complete germination time were 14,16 and 18 d of 1.0 , 2.0 and 3.0 kGy ,respectively.The time onger than control 2,4 and 6 d respectively. Germ tube elongation and hyphal branching has been suppressed effectively.Under the conditions of 5℃,24 h, germ tube length of 1.0 kGy was only 41.42μm, the ratio was 65.75%of the control. 1.0 kGy treatment did not produce hyphal branches after cultured 48 h under 5℃. In addition, the electron beam irradiation could reduced the virulence of conidia.The disease index of 2.0 kGy treatment was 4.17, 2.60 and 15.28under 25℃, 2d; 10℃, 9 d and 5℃, 15 d respectively,while the control were up to 25.00,18.36 and 62.50 respectively.2. Used mycelium of B. cinerea was the study objective.Made use of induced culture medium of shaking cultured after electron beam irradiated,then tested the cell wall degrading enzyme activity and the virulence of mycelial. The results showed that: when the activity reached peak, the control group activity of polymethyl galacturonic acid enzyme, pectinase, carboxymethyl cellulose andβ-glucosidase were 424.55 u / g, 436.00 u / g, 35.67 u / g and 306.72 u / g, and 2.0 kGy irradiated treatments activity peak were 301.01 u / g, 361.41 u / g, 19.05 u / g and 178.35 u / g,respectively. At the same time, it could reduced the mycelium's virulence after irradiated: time, the disease index of 2.0 kGy treatments were 2.78, 44.44and 13.89 under the conditions of 25℃, 2d,10℃and 5℃, 15 d,while the disease index of controls were up to 19.44,98.61 and 61.11 respectively.3.Electron beam irradiation could delayed the incidence of strawberry, inhibited lesion diameters, increased enzyme activity which associated with the disease and the contents of disease-resistant substances significantly. 1.0 kGy treatment could significantly reduced the incidence and delayed the incidence and lesion diameter of strawberry, and increased the activity of SOD, POD, PAL which were associated with their disease resistance (P <0.05). When reached the enzyme activity paek, POD activity were 506.67 u / g and 556.67u / g of 1.0 kGy treatment under 25℃and 5℃, but the activities controls were 506 u / g and 493.94 u / g under 5℃and 25℃; SOD activity was 69.92 u / g and 254.04 u / g, reached 1.26 times and 1.54 times of control groups ; PAL activity in the control groups were 98.27 u / g and 108.13 u / g, respectively, the activities were 72.15% and 84.74% of 1.0 kGy treatments. Meanwhile, the irradiation could improved the contents of flavonoids, total phenolics and lignin in certain degrees,and increased the ability of the fruits own resistance,too.
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