| Monitoring of fungicide resistance to 3 different types fungicide of Botrytis cinerea , which were isolated from tomato collected in 4 different level of fungicide application?greenhouse of Shangdong Province during March-april in 2000. The, level and frequency of resistance of different class of strains were carried out. The sensitivity and cross-resistant of different class of strains collected from greenhouse to fungicide were examined in vivo and vitro. The resistance selection of Botrytis cinerea which were sensitive or resistant to diethofencarb were carried out. The fitness of different class of strains was studied. The resistance mechanism to carbendazin, procymidone and diethofencarb was evaluted. Toxicity of twelve fungicides was tested with mycelial growth of Trichoderma viride, T. aureoviride, T. lamatum and T. harzianum in the laboratory. Mutants resistant to carbendazin and procymidone from parental strain of T. Harzianum were induced. The fitness, antagonistic and toxicity of secondary metabolite were examed in vivo and vitro. The results could be summarized as follows: 1.Studies on multiple fungicide resistance to Botrytis cinerea(1) The result showed that the percentages of carbendazin+ procymidone+diethofencarb-resistant strains were 53.7%, the percentages of carbendazin+procymidone-resistant strains were 100% in Shouguang Fengcheng; the percentages were 6.8% and 72.7%, 0% and 3.4% in Taian Liangzhuang and Taian Huangjiazhuang, spectively.The isolates were all sensitivity strains in Xintai Longting where the greenhouse were founded justly. All carbendazin-resistant strains showed high level of resistancd (EC50>100mg/mL), all procymidone-resistant strains showed low level of resistant (lmg/lL< EC50<10nig/mL) , all carbendazin+diethofencarb-resistant strains showed low level of resistant (0. 9mg/L < EC50<4mg/mL).A new phenotype of Botrytis cinerea was found. The new phenotype were highly resistant to carbendazin, and lowly resistant to diethofencarb. Accordingly, the new phenotype was designated BRNLR.(2) The multiple resistant strains can maintain their resistance after 8 successive incubation on the fungicide free PDA.54(3) The resistance selection of BRN' and BRNLR strains were carried out on PDA amended with diethofencarb which concentration was O.lmg/L and 5mg/L, respectively. The resistant level of diethofencarb was not increased after 20 successive incubation.(4) The result of toxicity of different fungicides to different class of strains showed that ,benzimidazoles-resistant strains had cross-resistant between carbendazin and diethofencarb, thiophanate-methyl, procymidone, iprodione and dimetachlone, negative cross-resistant between benzimidazoles and diethofencarb. The toxicity of fludioxonil was the highest (EC50<0. 02mg/mL) to different class of strains, the late were pyrimidifen, tebufenozide, flusilazol and propiconazol((EC50200mg/mL).(5) In fitness, the multiple fungicide resistant strains, sensitive strains and other class of strains showed similar radial growth rates, osmotice sensitivity and pathogenicity, but multiple fungicide resistant strains prouded fewer conidia and most sclerote than sensitive strains.(6) The result showed that upon treatment with carbendazin, procymidone and diethofencarb: the sensitive strain had strange absorbent banding activity, it can absorb number of carbendazin, but resistant to carbendazin strain didn't show that activity. Diethofencarb caused more eletrolyte leakage of the multiple resistant strain under 0.02mg/L concentration. Celler leakage from different class of strains didn't differ after 3hr incubation.(7) The activity of PAL of different classof strains werer increased when they treated with limited concentration after limited time, but their activity were...
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