【作者】 李泓达；

【导师】 高必达；

【作者基本信息】 湖南农业大学 ， 植物保护， 2008， 硕士

【摘要】 水稻纹枯病(Thanatephorus cucumeris)是世界性的水稻病害之一,该病在湖南省发生为害严重,已成为夺取水稻高产、稳产的主要障碍。本研究采用室内生物测定和田间小区试验相结合的方法,研究了多菌灵、福美双、满穗、井冈霉素等药剂以及不同配比对水稻纹枯病的联合作用。得到如下结果:1、离体茎段浸药法是测验井冈霉素生物活性的最佳方法通过菌丝生长抑制法、离体茎段内吸法、离体茎段浸药法3种生测方法对水稻纹枯病进行了室内生测试验,试验结果表明,井冈霉素在内吸试验中的Ec50最大,在菌丝生长抑制试验中次之,在浸药试验中最小,这就说明在浸药试验中,井冈霉素表现的生物活性最强,与井冈霉素在大田中的防治效果最接近,所以用离体茎段浸药法是测验井冈霉素生物活性的最佳方法。2、通过室内毒力测定,研究发现,多菌灵、福美双和福美双多菌灵混混剂对纹枯病菌都有较强的抑制作用,Ec50值分别为2.68μg/mL,3.05μg/mL,1.80μg/mL,两者共毒力系数为164.9。而井冈霉素、满穗及满穗井冈霉素混剂的Ec50值分别为17.94μg/mL,0.1789μg/mL,0.9727μg/mL,两者共毒力系数为1097.8,明显优于福美双多菌灵混剂。因此选择井冈霉素满穗混剂作为田间药效试验药剂。3、满穗与井冈霉素混合施用对水稻纹枯病具有较高的防治效果满穗与井冈霉素混合施用明显优于井冈霉素的效果。在用药量减少的情况下满穗与井冈霉素混剂与满穗在推荐用量下单用的防病效果和增产效果相当,可大大降低成本,减少农药污染。虽然满穗与井冈霉素混剂1的防治效果(87.5%)要高于满穗与井冈霉素混剂2的防治效果(84.6%),但在增产方面,满穗与井冈霉素混剂2要高于满穗与井冈霉素混剂1,综合考虑,推荐用药组合为满穗与井冈霉素混剂2,即满穗与井冈霉素液(满穗和井冈霉素有效成分比例为1:100)每亩用量50mL,加水50Kg喷施。更多还原

【Abstract】 Rice sheath blight caused by Thanatephorus cucumeris is one of the major rice diseases in the world. In Hunan Province, rice sheath blight is the main obstacle to limit high and rice, stable yield. In this study, different combined ratio of carbendazim, thiram, Manshui, Jinggangmycin were used to investigate their effecacy to rice sheath blight approved through the laboratory bioassay and field experiment . The results are as follows:1. In vitro stem with soaking is the best method for expression of the biological activity of Jinggang mycinThree bioassay methods mycelium growth inhibition test, in vitro stem absorption test and in vitro stem soaking Jinggangmycin were used to text activity of Jinggangmycin to T. cucumeris. The results showed that the Ec50 value of Jinggangmycin is largest for the in vitro stem absorbtion test, mycelium growth inhibition test is the second. The smallest Ec50 value is the in vitro stem soaked test, reflecting the field control of Jinggangmycin.2. In Laboratory test, this research studied the toxicity test of diferent pestiside The result indicate Carbendazim, Thiram and well-being of more than sheath blight fungus has a strong inhibitory effect, Ec50 values were 2.68μg/mL, 3.05μg/mL, 1.80μg/mL ,The values of two virulence factor were 164.9. The Ec50 value of the Jinggangmycin, Shui Po and the mixture were 17.94μg/mL, 0.1789μg/mL, 0.9727μg/mL, a total of two virulence factor of 1097.8, much better than the former mixture. Therefore choose Jinggangmycin Shui Po as a mixture of the field trial.3. The mixture of Man Sui and Jinggangmycin (M-J) has high effect to protect rice sheath blight, and is better than Jinggangmycin alone. when reduce the dosage, M-J has the same effect with Man Sui in a recommended amount. This also can save the costs and reduce pesticide pollution. Although the control effect of M-J 1 (87.5 %) is higher than that of the M-J 2 (84.6%), but for increasing rice production, B-J 1 is better than M-J 2. According to these results, we recommend that it is suitable to use M-J 2, (Man Sui mixed with Jinggangmycin by 1:100 of active ingredients), 50mL/667m2 , add water 50Kg for spraying.更多还原