摘要：

Selective inhibition of bacterial or fungal growth in remoistened, oven-dried, inoculated Andosols indicated that bacteria were a more important source of benzyloxycarbonyl- l -phenylalanyl- l -leucine hydrolyzing activity (z-FLase) and casein-hydrolyzing activity (caseinase) than fungi. The same test indicated that bacteria were also a more important source of soil caseinase under upland conditions in a Gray Lowland soil. Most of the proteolytic bacteria isolated from the three upland fields by azocoll agar plates (Andosol upland field, 100%; Andosol uncultivated field, 96.4%; Gray Lowland upland field, 70.0%) were Bacillus spp. Most (100%, 97.1%, and 84.0%, respectively) of the gelatin liquefiers selected from the azocoll degraders, as those with high extracellular z-FLase and caseinase, were also Bacillus spp. We conclude that Bacillus spp. are the major source of soil protease in the three upland fields studied.

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