Civitas Pre-M1xed安全性评价及其对烟草赤星病的防治效果

Civitas Pre-M1xed (简称Civitas)是加拿大石油公司生产的一种食品级合成异链烷烃乳化剂化合物。本研究采用种子萌发和盆栽试验法评估了Civitas的安全性，同时利用菌丝生长速率法测定了烟草赤星病菌 Alternaria alternata 对Civitas的敏感性，并采取盆栽方式评估了Civitas对烟草赤星病的防治效果。结果表明:相较于对照(种子萌发率82.7%)，体积分数为1%和0.1% (体积分数，以下同)的Civitas水溶液对烟草种子的萌发无抑制作用，而5%和10% 的Civitas水溶液对种子的萌发有抑制作用，萌发率分别为58.3%和32.1%。20%和10%的Civitas水溶液对团棵期的烟株株高和茎围有一定抑制作用，而5%和1%的Civitas水溶液则无明显影响；尽管不同供试体积分数的Civitas水溶液对现蕾期的烟株株高生长无抑制作用，但20%和10% 的Civitas水溶液对该时期烟株的茎围生长有一定的抑制作用。此外，不同体积分数的Civitas水溶液对烟草赤星病菌均表现出一定程度的抑制活性，且随Civitas体积分数的增大而增强，20%的Civitas水溶液抑制率为54.1%。Civitas对烟草赤星病同时具有保护和治疗作用，5% 的Civitas水溶液直接喷洒烟叶10 d后，保护作用和治疗作用的防效分别为59.3%和19.6%。相关的研究结果可为Civitas的进一步安全性评价及潜在应用研究提供参考和依据。

Safety evaluation of Civitas Pre-M1xed and its effect on brown spot disease of tobacco

Civitas Pre-M1xed (referred to as Civitas) is a food-grade synthetic isoparaffin emulsifier compound produced by Petro-Canada. The safety of Civitas was evaluated using seed germination and pot experiments in this study. At the same time, the sensitivity of Alternaria alternata isolated from tobacco to Civitas and the effects of Civitas on tobacco brown spot disease were determined using mycelial growth rate and potting methods. The seed germination rate of the control was 82.7%. After treated by 5% and 10% aqueous solution of Civitas, the seed germination rates decreased to 58.3% and 32.1%, respectively, while 1% and 0.1% of Civitas had no significant inhibitory effect on seed germination. 20% and 10% aqueous solution of Civitas had a certain inhibitory effect on the plant height and stem circumference in the rosette stage. However, 5% and 1% aqueous solution of Civitas had no such effect. None of the tested aqueous solutions of Civitas had inhibitory effect on the growth of the plant height in the bud stage, but 20% and 10% aqueous solution of Civitas had a certain inhibitory effect on the stem growth during this stage. In addition, the aqueous solutions of different volume fraction of Civitas showed a certain degree of inhibitory activity againstA. alternata, and the inhibitory effect which was improved with the increase of volume fraction. When the volume fraction of Civitas solution was 20%, the inhibition rate was 54.1%. Civitas exhibited curative and preventive effects against tobacco brown spot disease 10 days after foliar spray treatment with 5% Civitas, disease of tobacco caused byA. alternatawas reduced by 59.3% in preventive trials, and by 19.6% in curative trials. The results have provided reference and basis for the further safety evaluation of Civitas and its potential applications.