【作者】 刘振海；

【导师】 张海清；

【作者基本信息】 湖南农业大学 ， 农学， 2011， 硕士

【摘要】 为探明宁南霉素对水稻立枯病和烟草花叶病(TMV)的防治效果及其作用机理,本研究采用室内菌丝抑制法和生长速率法,用宁南霉素对水稻立枯病的优势菌尖孢镰刀菌、立枯丝核菌和腐霉菌进行了抑制率和毒力测定,并通过田间小区试验测定了宁南霉素对水稻立枯病的防治效果和秧苗素质的影响。通过田间试验、生物测定、血清测定等方法分析了宁南霉素对TMV的防治效果及其作用机理。主要研究结果如下：1.用2%宁南霉素水剂200倍、300倍、400倍液处理,对水稻立枯病的三种优势菌尖孢镰刀菌、立枯丝核菌和腐霉菌的抑制效果以200倍液的处理效果最佳,在接种后第7天的平均抑制率分别为74.9%、65.9%、和69.6%；对立枯菌菌丝生长速率的抑制效果最明显。半效应浓度(EC50)为34.49mg/L；随着宁南霉素用量增加,对立枯病防效提高,以12.5g/m2-25g/m2效果较优；宁南霉素处理对水稻秧苗素质略有促进作用。2.宁南霉素对烟草花叶病毒病(TMV)有较好的防治效果,且具有促进烤烟生长的功能,增产效果明显。使用浓度以75 ppm效果最好。对TMV的防效作用主要通过延长病害潜育期,抑制烟草花叶病毒蛋白合成,降低植株体内病毒粒体浓度以及调节机体代谢等途径达到提高机体抗病的能力。更多还原

【Abstract】 For a better understanding of the optimum utilizing concentration of Ningnan Mycin Ferment on rice Rhizoctoniarot and Tobacco Mosaic Virus (TMV), two methods including restraining of indoor hypha and the speed of growth were used in this study. The inbibiting rate and toxin degree to three superior strains Fusarium oxysporum Schelcht, Rhizoctonia solan Kuhn and Pythium sPP of rice Rhizoctoniarot were tested after treated with Ningnan Mycin Ferment. And the field applying experiment was also performed to test the controlling effect and evaluate the health of rice seedling. The main results were as follows:1. The average inhibition rate of 2% Ningnan Mycin Ferment with the concentration of 200 times treatment to three superior strains of rice Rhizoctonia, Fusarium oxysporum Schelcht, Rhizoctonia solan Kuhn and Pythium sPP were 74.9%,65.9% and 69.6%, respectively on the 7th day after inoculation, ranked the first among the three treatments of 200 times,300 times and 400 times. It expressed the best control effect to Rhizoctonia solani hyphae growth rate on the three strains of rice Rhizoctoniarot. The 50% effect concentration (EC50) was 34.49 mg/L. The results also showed that the control effect on Rice Rhizoctoniarot were much better with the increasing of the using dosage of Ningnan Mycin Ferment, and the best dosage was 12.5g/m-25g/m. In addition, the results indicated Ningnan Mycin Ferment had an improving effect to the health of rice seeding growth.2. Ningnanmycin had a signifcant control effect on tobacco mosaic virus (TMV), and had the function of promoting growth. Applying concentration of 75 ppm worked best. The results of serum mensuration indicated that the main defense mechanism of Ningnan Mycin Ferment is to prolong the term of disease latency, inhibit the protein synthesize of TMV, decrease the consistence of toxin in plant and adjust plant metabolism to prevent the infection of virus TMV.更多还原