研究了稀土氧化镧（Ｌａ２Ｏ３）对水稻白叶枯病菌（ＸａｎｔｈｏｍｏｎａｓｏｒｙｚａｅＰｖ．ｏｒｙｚａｅ，简称Ｘｏ）生长及胞外酶活性的影响。稀土浓度为５０、１００、１５０、２００、２５０、３００、３５０ｍｇ／Ｌ时，对Ｘｏｏ生长均呈抑制作用，在固体培养中菌落出现时间延迟，直径减小，液体培养中ＯＤ６２０值下降；稀土浓度大于３５０ｍｇ／Ｌ时，病菌停止生长；浓度为２００ｍｇ／Ｌ时，稀土对Ｘｏ的蛋白酶、果胶酶活性有明显的刺激作用，对纤维素酶活性无明显影响 The effect of rare earth lanthanum oxide (La2O3) on the growth and extracellular enzyme activity of Xanthomonas oryzae Pv.oryzae (Xo) was studied. When the concentration of rare earth was 50, 100, 150, 200, 250, 300 and 350 mg / L, the growth of Xoo was inhibited. In the solid culture, the colony appeared delay time, the diameter decreased, OD620 value decreased in liquid culture; When the concentration was more than 350mg / L, the bacteria stopped growing. When the concentration was 200mg / L, the rare earth had a significant stimulating effect on the protease and pectinase activities of Xo, but had no obvious effect on the cellulase activity