镧对青枯假单胞菌生长及若干生化性状的影响

单一稀土氧化镧Ｌａ２Ｏ３对青枯假单胞菌的生长有明显抑制作用。当Ｌａ３＋质量浓度为５０，１００，１５０，２００，２５０，３００，３５０ｍｇ／Ｌ时，与对照相比，固体平板上病菌初生长时间延迟，７天后的菌落直径减小，生长量也减少。液体培养中的生物量也比对照显著下降。当Ｌａ３＋质量浓度大于３５０ｍｇ／Ｌ时，病菌停止生长。浓度为２００ｍｇ／Ｌ的Ｌａ３＋明显刺激该病菌的胞外蛋白酶、果胶酶及纤维素酶活性。

Effect of Rare Earth on the Growth and Some Biological Properties of Pseudomonas Solanacearum

The effect of rare earth (RE) on the growth and the activities of extracellular enzymes of pseudomonas solanacearum(V z) was studied.At the concentrations of 50,100,150,200,250,300 and 350mg/L,RE delayed the initial time of growth,slowed the growth rate in solid medium and decreased the biomass in liquid culture of A z.When the concentration of RE was greater than 350mg/L,the growth of A z was inhibited completely.At 200mg/L,the activities of protease,pectinase and cellulase were stimulated obviously and RE had more influence on promotion of the activities of pectinase and cellulase than on that of protease.