Abstract: A series of rice seed inspection technique by rice leaf in vitro test for Xanthomonas campestris pv. oryzicola were established after 3-year studies. With the method 44 samples of natural infected rice seeds of bacterial leaf streak were successfully inoculated onto the rice leaves in vitro, and produced lesions and bacterial beads on them. The method reveals young rice leaves in vitro on 1% water agar with 90 ppm of benzimidazole in petri dishes maintains green for 15-20 days under saturation of relative humidity, light of flurescent lamps at days or nights and temperature of 30℃, which satisfies the needs of the time for induction of lesions and bacterial beads. Due to these suitable conditions, concentration suspension of the samples of diseased seeds in weight of 1.2-4.0g can be inoculated onto young rice leaves in vitro with an insect needle, the lesions and bacterial beads appeared at 3 days and 5.5-8.5 days after inoculation respectively. The lowest concentration of the pure culture for the symptom induced is 5×10³ cells/ml in this method.

Key words: Xanthomonas campestris pv. oryzicola, Seed inspection, Rice leaf in vitro, bacterial bead

摘要： 经3年研究建立了一套用离体稻叶检测稻种带细条病菌的方法，应用该方法成功地将44份自然发病的细条病病种接种到离体稻叶上并产生菌脓。甩1％水琼脂加90 ppm无毒苯口并咪唑．在30℃下可使水稻幼苗的离体叶保持15～20 d，可满足细条病接种发病的时间需要。应用纯菌测定该方法的灵敏度，最低可检测浓度为5×10^3 Cells／ml。由于选择了最佳的温度、湿度/光照、苗龄及其它有关环境条件， 使1．2～4．0 g的病种经研碎浸泡后浓缩针刺接种干离体稻叶上在3 d后出现病斑，5.5～8.5 d后产生菌脓，与其它血清学检测方法相比，离体检测法具有直观、可靠、简便、稳定等优点。特别可避免由于种子携带丧失活性的细条病菌或其它病菌而引起的误诊。

关键词: 水稻, 细菌性条斑病, 种子带菌, 检测技术