镧对青枯假单胞菌生长及若干生化性状的影响

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

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。

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.