不同培养条件下甲霜灵在蓖麻幼苗韧皮部的输导性

Phloem mobility of metalaxyl in Ricinus communis seedling under different culture conditions

甲霜灵是一种能通过植物叶片吸收后在韧皮部向下传导的杀菌剂,为了探明其在韧皮部的传导规律,以蓖麻幼苗为模式植物,通过改变试验过程培养液中甲霜灵含量、pH值以及培养的温度、时间及光照等因子,采用气相色谱-质谱联用（GC-MS）方法,检测了不同培养条件下蓖麻幼苗韧皮部渗出液中甲霜灵的含量。结果表明：光照对甲霜灵在蓖麻幼苗韧皮部中的输导性无显著影响;当培养液中甲霜灵质量浓度为400 mg/L时,其在蓖麻幼苗韧皮部中输导量最大;当培养液pH值为5.5时,甲霜灵在蓖麻幼苗韧皮部中输导量最大;当培养温度为28℃时培养效果最佳,温度过高或过低均会使甲霜灵在蓖麻幼苗韧皮部中的输导量减少;培养3 h以上,蓖麻幼苗韧皮部渗出液中甲霜灵的含量显著高于前2 h渗出液中甲霜灵的含量。该研究优化了蓖麻幼苗获得药剂最大吸收时的适宜培养条件,为检测其他未知化合物在植株韧皮部中的输导性提供了参考。

Metalaxyl is a fungicide which can translocate basipetally in phloem after absorbed by leaves. In this study, the phloem mobility of metalaxyl was investigated. The Ricinus communis seedling was used as the model plant. The contents of metalaxyl in the phloem sap under different culture conditions were detected by gas chromatography and mass spectrometry（GC-MS）. Cultural factors such as the concentration of metalaxyl, pH value of buffered solution, incubation temperature,incubation time and light condition were studied. The results indicated that the light has no significant influence on the mobility of metalaxyl in phloem sap of R.communis. And under the experimental conditions, the highest contents of metalaxyl in phloem of R. communis was observed when the concentration of metalaxyl in the incubation solution was 400 mg/L. The highest contents of metalaxyl in phloem of R. communis was observed when the p H value of incubation solution was 5.5. And the optimal incubated temperature was 28 ℃, too high or low temperature will reduce the contents of metalaxyl in the phloem of R. communis. The contents of metalaxyl in phloem sap increased significantly within the first 3 hours, which was significantly higher than that within the first 2 hours.Suitable conditions for the maximum absorption of R. communis was optimized in this study, and provide a reference for other unknown compounds to detect their phloem mobility in R. communis.