【作者】 廖薇；

【导师】 杨志荣；

【作者基本信息】 四川大学 ， 农药学， 2004， 硕士

【摘要】 姜瘟病又名姜腐烂病、青枯病，对生姜种植是一种严重的毁灭性病害。姜瘟发生早、危害大，危害轻的造成减产减收，重的造成严重减产或无收，严重影响了姜农的重要经济收入。本文从自然罹病的姜块上和土壤中用梯度稀释法分离出姜瘟病病原菌，按《伯杰氏细菌鉴定手册》（第八版）鉴定为青枯假单胞菌（Pseudomonas．Solanacearum）。 对于姜瘟病长期都是采用药物防治，但至今还未有一种特效药。本文比较了现有的数种农药及抗生素的抑菌效果，筛选出两种青枯假单胞菌的抑制物——A：2，4，4’-三氯-2’-羟基-联苯醚（俗称三氯新）和B：2，4，4’-三氯-5’-溴-2’-羟基-联苯醚，其最小抑菌浓度可达1×10^-7g／ml。 本文研究了化合物B对青枯假单胞菌的作用时间，发现该化合物能在青枯假单胞菌的对数生长期和稳定期起到抑制及杀灭作用，且随着化合物浓度的升高，杀灭效果更明显。而且用药后，青枯假单胞菌的一个显著致病因子——胞外多糖的分泌有明显减少。通过³H标记的胸腺嘧啶核苷的同位素示踪研究，发现该化合物能极为显著影响青枯假单胞菌的DNA合成。单因素方差分析结果证明化合物的浓度差异对细菌DNA合成有显著影响。显著性检验证明化合物浓度为Zm留ml时即可达到最大防治效果。结合扫描和透射电镜照片发现化合物能引起细菌染色质（DNA）固缩，破坏细菌细胞壁，使细菌细胞形态发生变化，最后崩解死亡，与同位素实验结果一致。关键词:姜瘟 青枯假单胞菌 2，4，4’一三氯一2’一经基一联苯醚 2，4，4’一三氯一S’一澳一2’一经基一联苯醚 作用机理更多还原

【Abstract】 Rot disease in ginger is a truculence disease to ginger planting. The reduction of output of the bad field can be up to 50 percent. The disease badly affects the pocketbook of ginger farmer. We isolated the pathogenic bacteria from the naturally affected ginger by dilute with grads, and identified them as Pseudomonas. solanacearum.It is controlled by medicament for long, but we still have not a specific medicine up to the present. We compared the inhibition of existing pesticides and antibiotics, used several medicaments to suppress them and find out the most two effectivecompounds-2,4,4’-trichloro-2’-hydroxy-diphenyl etherand 2,4,4’-trichloro-5’-bromine-2’-hydroxy-diphenyl ether which MIC are1 X 10-7g/mlStudying on the time of the suppression medicament working, we found the compounds can control and killPseudomonas. solanacearum during its logarithmic phase and stable trophophase. Along with the increasing of the compound’s concentration, the effect is more obvious. Afterusing the medicament, the main factor of causing disease-extracellular polysaccharide, secreted by bacteria, is obviously reduced. Then we did the isotopic tracing marked by 3H -TDR and found this compound can evidently affect the The result of one-factor analysis of variance proved the difference of compound’s concentration can do remarkable effect to the synthesis of the DNA of the bacteria. Significance test proved that the compound could reach the best control effect when its concentration is 2mg/ml. Through the photos of electron microscope, we found the compound can make the bacteria’ chromatin pycnosis and destruct the formation of the cell wall then break the bacteria which is the same to the result of isotopic tracing.更多还原