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水稻白叶枯病菌ＪＸＯＩＩ细胞悬浮液及其分泌的毒素溶液接种到烟草叶片中，都能在烟草叶片上产生快速的坏死反应。引起坏死反应所需的最短时间分别为接种后８ｈ和０．５ｈ。低浓度的ＪＸＯＩＩ（＜１０７ｃｆｕ／ｍｌ）接种后３６～４８ｈ内形成褪绿斑，而低浓度的毒素（＜２．５ｍｇ／ｍｌ）接种后随时间延长在接点无任何可见变化。依文斯蓝（Ｅｖａｎｓｂｌｕｅ）染色发现，毒素和ＪＸＯＩＩ分别在接种后０．５ｈ和６ｈ内细胞大量死亡。叶圆片法测定表明，接种毒素后２ｈ内烟草细胞膜透性迅速上升，接种ＪＸＯＩＩ后９ｈ细胞膜透性开始明显上升。毒素处理的烟草叶片中ＬＯＸ、ＰＯＸ、ＳＯＤ、ＣＡＴ活性水平较对照降低，而ＪＸ－ＯＩＩ处理中上述酶活性较对照有不同程度的增加。蛋白质合成抑制剂环己酰亚胺，ＲＮＡ合成抑制剂放线菌素Ｄ和钙离子通道阻断剂氯化镧分别以７．１×１０－５Ｍ、１×１０－４Ｍ和１×１０－３Ｍ浓度有效地抑制ＪＸＯＩＩ在烟草上形成坏死反应，这些抑制剂对毒素在烟草上的坏死反应则没有影响。
Inoculation of the bacterial suspension of X. oryzae JXOII cell suspension with its secreted toxin solution into tobacco leaves produced a rapid necrotic reaction on tobacco leaves. The minimum time required for necrotic response was 8 h and 0.5 h, respectively. At low concentrations of JXOII (<107 cfu / ml), chlorotic spots developed within 36- 48 h after inoculation, whereas no visible change at the junction with prolonged exposure to low concentrations of toxins (<2.5 mg / ml). Evansblue staining revealed that a large number of toxins and JXOII died within 0.5 h and 6 h after inoculation, respectively. The leaf disk method showed that the cell membrane permeability of tobacco increased rapidly within 2h after inoculation of toxin, and the membrane permeability began to increase obviously 9h after inoculation of JXOII. The levels of LOX, POX, SOD and CAT in tobacco leaf treated with toxin were lower than those in control, while those in JX-OII treatment were increased to some extent compared with the control. The protein synthesis inhibitors cycloheximide, RNA synthesis inhibitor actinomycin D and calcium channel blocker lanthanum chloride were treated with 7.1 × 10 -5 M, 1 × 10 -4 M and 1 × 10 -3 M The concentration of JXOII effectively inhibits the formation of necrotic reactions in tobacco, and these inhibitors have no effect on the toxin’s necrotic response to tobacco.