杀菌剂对合欢枯萎病菌的毒力测定

采用抑菌圈法和生长速率法对合欢枯萎病菌进行杀菌剂毒力测定的结果表明：多菌灵、根府咛、硫磺·多菌灵、福美双、代森锰锌等杀菌剂对合欢枯萎病菌有明显的抑菌效果;多菌灵、根府咛、硫磺·多菌灵的抑菌效果较好,可望应用于合欢枯萎病的大田防治试验。     

Sensitivity of Sclerotinia sclerotiorum from oilseed crops to boscalid in Jiangsu Province of China

Between 2006 and 2008, 120 isolates of Sclerotinia sclerotiorum from the Jiangsu Province of China were characterized for the baseline sensitivity to boscalid, a new active ingredient that interferes with succinate ubiquinone reductase in the electron transport chain of fungi. The isolates collected between 2006 and 2008 all showed similar sensitivity to boscalid. Baseline sensitivities were distributed as unimodal curves with mean EC₅₀ values of 0.17 ± 0.09 μg ml⁻¹ for inhibition of mycelial growth. Inhibition of mycelial growth of isolates whether they had resistance to carbendazim or, dimethachlon or dual resistance to both carbendazim and dimethachlon was similar, suggesting that there was no cross-resistance between boscalid and MBC/dimethachlon already in commercial use. In field trials, the treatments boscalid (50% WG), at 125, 187.5 and 250 g ai ha⁻¹ provided higher control efficacies of 65.2, 69.0 and 75.1%, respectively, than the treatments carbendazim (50% WP), at 750 g ai ha⁻¹ and dimethachlon (46% WP), at 690 g ai ha⁻¹ with control efficacies of 18.9 and 44.6%, respectively.     

Effects of fungicides on the occurrence of winter wheat eyespot caused by fungi Oculimacula acuformis and O. yallundae

The aim of this study was to estimate the effect of fungicides on the occurrence of Oculimacula spp. on winter wheat stems using real-time polymerase chain reaction (Real-time PCR) method. The ratio of Oculimacula yallundae and Oculimacula acuformis in the population was assessed from 2009 to 2011 in the winter wheat crops after 2, 3, and 4 years of use of fungicides prochloraz, cyprodinil, prothioconazole, metrafenone, and boscalid. After 4 years of fungicide use, the highest relative reduction of DNA of both fungi, compared with the unsprayed control, was detected in the samples from cyprodinil-applied plots. Relatively less O. yallundae DNA was identified in the samples from prochloraz- and that of O. acuformis from prothioconazole-applied plots. Metrafenone and boscalid had little effect on the changes in Oculimacula population. Fungicide effect on O. acuformis and O. yallundae pathogenesis slightly differed. In Oculimacula population under the fungicide treatment, 10 days after application (BBCH 37), the ratio of O. acuformis in all treatments was reduced, but the ratio of O. yallundae was increased in prevalence compared to O. acuformis in cyprodinil and prothioconazole treatments. Later in the season (BBCH 75), the ratio of O. acuformis increased in metrafenone and O. yallundae in prochloraz treatments. The effect of fungicides used for eyespot control on winter wheat productivity was inconsistent. Prochloraz use led to a significant grain yield increase in 2010, while prothioconazole use showed a similar increase in 2009 and 2010. Cyprodinil, boscalid, and metrafenone did not have any effect on the yield in any of the experimental years. A significant increase in thousand grain weight was obtained in prochloraz, prothioconazole, and boscalid treatments.     

5种杀菌剂对12种真菌生长的影响

[目的]筛选出既能抑制霉菌又不影响食用菌生长的杀菌剂及其适宜的使用浓度。[方法]通过食用菌菌丝和霉菌的培养及抑菌试验,研究了5种杀菌剂对12种真菌生长的影响。[结果]克霉灵250倍液有效抑制青霉,对灵芝和黑木耳（29）没有抑制作用。克霉净400倍液有效抑制青霉,对灵芝没有抑制作用。多菌灵600倍液有效抑制曲霉和青霉,对杏鲍菇和黑木耳（29）没有抑制作用。菇宝对曲霉的有效浓度分别是1 500和2 500倍液,菇宝2 500倍液对白金针、香菇、黑木耳（29）、杏鲍菇、桑黄和冬虫夏草没有抑制作用。50%氯溴异氰尿酸对3种霉菌的有效浓度分别是800和1 200倍液,50%氯溴异氰尿酸1 200倍液对白灵菇、黑木耳（29）、灵芝和杏鲍菇没有抑制作用。[结论]该研究为杀菌剂在菇类种植中的应用提供了依据。     

生防菌绿色木霉对几种枯萎病菌的抑制作用

为了比较木霉菌(Trichoderma)对植物病原菌的拮抗作用效果,利用对峙平板法测定了绿色木霉菌及木霉菌和杀菌剂联合使用对几种枯萎菌的拮抗作用。通过对峙培养可以观察到,多数情况下,接种后3d内绿色木霉菌即可与病原菌接触,随后覆盖或侵入病原菌菌落内,从而抑制或阻碍其生长。木霉菌单独使用时有一定的抑菌效果,与杀菌剂联合使用比单用杀菌剂效果更显著,其中以绿色木霉菌+咪酰胺联合使用的效果最好,对西瓜枯萎病菌的抑制率达到了79.3%,对香蕉枯萎病1号小种的抑制率达到59%。     

3种药剂对草莓白粉病的防效评价

通过盆栽试验和大田试验,测定了42.5%吡唑醚菌酯·氟唑菌酰胺SC(2000、3000、4000倍液)、30%氟菌唑WP(2000、2400、3000倍液)和50%醚菌酯WG(2000、3500、5000倍液)3种药剂对草莓白粉病的防治效果。结果表明:盆栽药效试验中,42.5%吡唑醚菌酯·氟唑菌酰胺SC2000倍液对草莓叶片白粉病的防效为90.81%,显著高于其他处理;30%氟菌唑WP最高防效为85.58%;50%醚菌酯WG最高防效为76.21%。大田试验中,42.5%吡唑醚菌酯·氟唑菌酰胺SC2000倍液对草莓叶片和果实白粉病的防效也最高,分别为98.20%和67.49%;30%氟菌唑WP最高防效分别为74.72%和60.78%;50%醚菌酯WG最高防效分别为76.00%和49.01%。3种药剂对草莓白粉病均具有不同程度的防效,对叶片白粉病的防治效果好于果实白粉病害,且试验浓度条件下无药害产生。     

6种药剂处理覆土对双孢蘑菇品质的影响

研究了6种药剂处理覆土后对双孢蘑菇子实体质量的影响.结果表明,各种药剂对双孢蘑菇的子实体形态和单菇重量影响不明显.疣克星稀释倍数为1 200倍、消毒剂稀释倍数为2 000倍～5 000倍、多菌灵稀释倍数为1 500倍～2 500倍、菇丰稀释倍数为2 000倍～2 400倍、甲基托布津稀释倍数为2 500倍时对双孢蘑菇增产明显;百菌清处理能降低双孢蘑菇产量.     

三种杀菌剂对子莲安全性的室内评价

在室内采用浸种和幼苗茎叶喷雾处理的方法,测定了3种常用杀菌剂多菌灵、丙环唑和嘧菌酯对子莲植株的安全性。试验结果表明,在供试的浓度范围内,以50％菌灵可湿性粉剂对子莲的安全性较高;25％丙环唑乳油较高浓度对子莲的生长具有明显的抑制作用;25％嘧菌酯悬浮剂则对子莲的幼嫩叶片较易产生药害。     

杀菌剂对蘑菇疣孢霉病的防治效果比较

通过在菇房中11种杀菌剂对蘑菇疣孢霉病防治效果和对双孢蘑菇生长影响试验,结果表明,11种杀菌剂对蘑菇疣孢霉病防治效果和对双孢蘑菇生长影响有明显差异,其中特克多45%悬浮剂500倍液无论是覆土处理或转潮时喷雾覆土处理,均对疣孢霉病有较好的防治效果,防治效率分别达93.7%和89.1%,且对双孢蘑菇菌丝生长和子实体发育无不良影响.其它杀菌剂综合表现均不理想.     

几种杀菌剂对吊兰白绢病的防治效果

[目的]筛选出防治吊兰白绢病的有效杀菌剂。[方法]以PVC盆栽吊兰为材料,采用叶面喷药方式,进行了5种杀菌剂防治吊兰白绢病的药效试验。[结果]菌核净、世高、丙环唑和烯唑醇对吊兰白绢病的防治效果优于恶霉灵,其中烯唑醇的防治效果最佳,达到91.90%;世高对吊兰白绢病的防治效果最快,1次用药后防效可达83.10%。[结论]为吊兰白绢病的防治提供了理论依据。