【作者】 杨勇；

【导师】 张学文；

【作者基本信息】 湖南农业大学 ， 细胞生物学， 2007， 硕士

【摘要】 薤白作为一种中药，具有抗菌消炎、抗血小板聚集、抗氧化、降低血压、防止动脉样硬化、抗肿瘤等药理作用，且不良反应少，药源广泛，是一种非常有开发价值的药用植物。但在农业生产中，薤白又是一种较难除去的顽固性杂草。生产实践中发现薤白对优良除草剂草甘膦具有较强的抗性。草甘膦的作用方式是抑制芳香族氨基酸的合成。本文以薤白为材料进行了愈伤组织诱导试验，同时使用6种浓度的草甘膦对其愈伤组织和植株进行了抗性研究，对于揭示薤白草甘膦抗性机制及农作物生产中对其控制和防除具有一定的指导作用。试验结果如下：（1）薤白愈伤组织的诱导MS基本培养基附加2，4-D、6-BA、NAA三种生长调节剂对薤白鳞茎组织进行愈伤组织诱导。在所实施的20个组合培养基中，MS+2，4-D 1.682 mg／L+NAA 1.009 mg／L+6-BA 1.682mg／L诱导效果很好。三者与诱导率（Y）之间的回归方程为Y=65.66—9.69X₁—4.95X₃—5.88X₁²—14.22X₂²—16.63X₃²。运用通用旋转组合设计，通过计算机模拟推测，最佳诱导培养基添加2，4-D，NAA和6-BA三种生长调节剂浓度最适范围分别是0.986～1.141 mg／L，0.930～1.088 mg／L和1.185～1.359 mg／L。（2）薤白愈伤组织草甘膦抗性薤白愈伤组织以不同浓度的草甘膦处理，表现出较高的草甘膦耐受性。薤白愈伤组织在草甘膦浓度值达到0.072 mol／L才开始出现愈伤组织部分坏死现象，同时在该浓度时愈伤组织的存活率仍为100％，而在草甘膦浓度达到0.096 mol／L时坏死现象加剧，存活率下降至60％。以草甘膦敏感烟草和蕌头为对照材料进行草甘膦处理，烟草愈伤组织在草甘膦浓度为0.012 mol／L时就出现大量坏死现象，在该浓度的成活率仅为20％，蕌头愈伤组织则不能耐受0.024 mol／L的草甘膦，其在该浓度的成活率只为20％。（3）薤白植株草甘膦抗性田间施用草甘膦，观察薤白植株形态变化。使用草甘膦后薤白叶片在0.011 mol／m²，0.022 mol／m²剂量组没有出现枯萎现象，而在0.044 mol／m²剂量组中虽然出现了枯萎现象，但不是太明显，而在浓度0.088 mol／m²剂量组出现了比较明显的枯萎现象，但30d后的成活率仍为70％，而在0.167 mol／m²剂量组中枯萎现象较明显，而30d后的成活率低于50％；测定其叶片叶绿素含量：草甘膦剂量处理组0.011～0.022 mol／m²的叶绿素含量没有明显的变化，说明草甘膦该剂量对薤白植株的处理的叶绿素含量影响不明显。而0.044 mol／m²、0.088 mol／m²和0.167 mol／m²的叶绿素含量均有不同程度的下降，这与试验观察的薤白植株有枯萎现象相一致。草甘膦剂量越大，叶绿素下降开始的时间越早，下降的幅度也越大。测定其可溶性蛋白含量：对照组中的可溶性蛋白含量维持了稳定的水平；而0.011 mol／m²和0.022 mol／m²的可溶性蛋呈现出先降后升的变化，说明薤白在进行草甘膦处理后，促进了薤白植株蛋白质的合成；0.044 mol／m²和0.088 mol／m²处理出现了比较大的波动，可能原因是草甘膦处理后薤白植株为了适应恶劣的坏境而增加的蛋白质的合成，所以出现先降后升的现象；0.167 mol／m²时初期蛋白含量急剧下降，后来下降的趋势有所缓和，最后仅有20％存活。因而可以得出薤白植株耐受草甘膦剂量为：0.088 mol／m²。建立薤白愈伤组织诱导生长调节剂浓度的最优组合，可以为建立一套薤白无性繁殖体系提供理论基础，同时为薤白愈伤组织草甘膦处理提供材料。对薤白愈伤组织草甘膦抗性的确定可以得出薤白对草甘膦的抗性并不是由于薤白植株的特殊外部结构引起的。确定薤白的草甘膦抗性剂量，可以为在农业生产中运用草甘膦对薤白的控制和防除提供最佳方案。更多还原

【Abstract】 Allium macrostemon Bunge is a Chinese traditional medicine herb which is usedfor aggregating antioxidant, depressing blood pressure, preventing atherosclerosis,antitumor pharmacy and so on. It is low in side-effects but widespread in the wild. Soit has been used as traditional Chinese medicine herb for a long time. But it is actuallya harmful weed in agriculture that is difficulty to be eliminated in field.Allium macrostemon Bunge showes strong resistance to glyphosate, a powerfulherbicide usually applied in herbs control. Glyphosate inhibits the synthesis ofaromatic amino acids in plants and be regarded as a safe and environment friendlyherbicide. To learn the mechanism how Allium macrostemon Bunge can resistant toglyphosate, the callus induction conditions for Allium macrostemon Bung.e culture areset. The induced callus are screened on glyphosate media to test its resistance ability.Field resistance test is also carried out under six grades concentration of glyphosatetreatment.The results are shown as follows:（1） That 2,4-D is the most important factor in callus inducing of Alliummacrostemon Bunge. The regression equation between inducing ratio of callus and thehormones is: Y=65.66-9.69X₁-4.95X₃-5.88X₁²-14.22X₂²-16.63X₃². Accordingthe equation, the optimal medium and hormone concentration are formulated out bycomputer evaluation. It is: MS+0.986～1.141mg/ L 2,4-D+0.930～1.088mg/LNAA+1.185～1.359mg/L 6-BA.（2） The glyphosate resistance of Allium macrostemon Bunge callus: Alliummacrostemon Bunge Callus grow on medium treated with different concentrations ofglyphosate. Allium macrostemon Bunge callus showes high tolerance to the herbicideglyphosate. The survival rate is 100% on 0.072 mol/L and is 60% when theconcentration reachs 0.096 mol/L while the controlling plants tobacco are verysensitive to the herbicide and all the callus putrescence on 0.012mol/L glyphosate medium with in 1 w. And the survival rate of Chinese onion, an other control plant,is 20％in 0.024 mol/L glyphosate. The highest tolerance of Allium macrostemonBunge callus is 0.096 mol/L.（3） Treating Allium macrostemon Bunge plant in field and the morphology areobserved. The leaves of Allium macrostemon Bunge are normal when glyphosate of0.011 mol/m² and 0.022 mol/m² are spraied. But it withering when the concentrationreachs to 0.044 mol/m² and the plant appears noticeably withered in a concentrationof 0.088 mol/m² glyphosate, However the plant survival more then 70％after 30 daysof the spray. Chlorophyll content in the leaves is test by spectrum. The chlorophyllcontent decreases more when higer glyphosate is applied. Then content showes anegative relationship with the applied glyphosate concentration. The soluble proteincontents in the leaves of different treatment are also analysied. It appears an initialincrease and later decrease in the treatment of glyphosate concentration 0.011 mol/m²and 0.022 mol/m². It appears relatively large fluctuations when the concentration of0.044 mol/m², 0.088 mol/m² and 0.167 mol/m² of glyphosate are applied. It isconclude that Allium macrostemon Bunge field tolerance to glyphosate in theconcentrations of 0.088 mol/m² spray.It is nessceray to establish an asexual reproduction system of Allium macrostemonBunge to learn its tolerance to glyphosate. The callus culture and inducing alsoprovides a speed propagation method for Allium macrostemon Bunge. The callustolerance of Allium macrostemon Bunge confirmes that the resistance to glyphosate ofthe plant in field is not due to the special machinical reason but may owe to atolerance enzyme EPSPs. The study may be helpful to establish a more efficientmethod to control the weed in field.更多还原