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对水稻细菌性条斑病菌胞外产物（胞外多糖、蛋白酶、果胶酸酯裂解酶、聚半乳糖醛酸酶、纤维素酶、淀粉酶、半纤维素酶）的部分特性以及不同菌株离体产生各胞外产物能力与致病力的相关性进行了初步研究．发现病菌在离体条件下分泌的各胞外产物总量和单位产量随培养时间的增长而增加，至一定的阶段后趋于稳定．不同培养基下各胞外产物的产生有所变化，但对各菌株之间单位产量的差异影响不大．病菌产生的蛋白酶、纤维素酶、淀粉酶、半纤维素酶和聚半乳糖醛酸酶活性最适ｐＨ值分别为９．０、６．０、８．０、４．０、８．０．其蛋白酶活性与致病力呈显著正相关，果胶酸酯裂解酶与致病力呈正相关．病菌除去胞外产物后，降低了在水稻叶片上的吸咐和增殖能力．强致病力菌株胞外产物对离体稻叶的伤害能力要强于弱致病力菌株．
Partial characteristics of the extracellular products of the bacterial strain of Bacteria (extracellular polysaccharides, proteases, pectate lyase, polygalacturonase, cellulase, amylase, hemicellulase) The correlation between the ability of each extracellular product to produce and the pathogenicity was studied preliminarily. It was found that the total amount of extracellular products secreted by the pathogen in vitro and the unit yield of the extracellular products increased with the growth of the culture time and stabilized to a certain extent. The production of extracellular products varied with different media, but had little effect on the difference of the unit yield among the strains. The optimum pH values of protease, cellulase, amylase, hemicellulase and polygalacturonase were9.0,6.0,8.0,4.0,8.0 respectively. The protease activity was significantly and positively correlated with pathogenicity. Pectate lyase was positively correlated with pathogenicity. Removal of extracellular products by the bacteria reduces their ability to attract and proliferate in rice leaves. Strong virulence strains of extracellular products in vitro injury of rice leaves stronger than weak virulence strains.