The Toxicity Determination And Field Application Of Wood Vinegar And Its Different Combinations With Tebuconazole On The Alternria Alternateesp.mal

In this study, according to virulent results of wood vinegar, we used it as synergist toconduct toxicity determination of its different combinations with tebuconazole on Alternriaalternatef.sp.mali by using growth rate method，then screened appropriate combination andconfigured corresponding pesticides to conduct field trials. The main results are as follow:1. The synergistic action of mixture of wood vinegar with tebuconazole indicated thatthe toxicity of different mixed proportion improved remarkablely. SR values were over1.5.When ratios of tebuconazole to wood vinegar were ranged1：1.4、1：2and1：11，it rached14.01、13.78and14.88. It showed significant synergistic action.2. The EC₅₀of different mixture of wood vinegar with tebuconazole against Alternriaalternatef.sp.mali were lower than6.5μg/g. Among the results, the antibacterial actives werebest when ratios of tebuconazole to wood vinegar were ranged1：1.4and1：2, the values oftheir EC₅₀were1.30μg/g and1.66μg/g.3. Compared with the standard fungicide, the trial pesticides had obvious controleffectiveness against Alternria alternatef.sp.mali. The control effect of48%tebuconazole·wood vinegar（16+32） SC’s3000-5000times against Alternriaalternatef.sp.mali was80%-88%on spring tip, and its control effect on autumn growth was82%-91%.The control effect of3000-5000times of another pesticide which is48%tebuconazole·wood vinegar（20+28） SC was81%-87%on the spring tip, and its autumngrowth’s control effect was80%-90%.4. The results of safety assessment indicated that trial pesticides had no adverse effects.The results of study indicates that mixture of wood vinegar with tebuconazole can notonly improve the control effect, but also reduce the amount of chemical pesticide substantially. According to the facters of economy, environment, safe, effect etc, werecommend to use48%tebuconazole wood vinegar （16+32） SC’s3000-4000times to sprayon the whole plant for controling the Alternria alternatef.sp.mali.