Effects of Four Plant Extracts on Inhibition of Phytophthora infestans
Min Fanxiang1, Guo Mei1, Hu Linshuang1, Wang Xiaodan1, Wei Qi1, Dong Xuezhi1, Ma Ji1, Lu Jun2 (1. Virus-free Seedling Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, Heilongjiang 150086, China; 2. Heilongjiang University, Harbin, Heilongjiang 150070, China)
The antifungal activity of the water and ethanol extracts from Stellera chamaejasma, Glycyrrhiza uralensis Fisch., Aconitum carmichaeli Debx., and Sophora flavescens Ait. were tested with Phyhtophora infestans (Mont.). The results showed that the four plant extracts had significant inhibitory effects on the P. infestans. ACS4(ethanol extracts from Sophora flavescens Ait.) was the best followed by HCS1(water extracts from Stellera chamaejasma), ACS3(ethanol extracts from Aconitum carmichaeli Debx.), and ACS2(ethanol extracts from Glycyrrhiza uralensis Fisch.), with EC50 being 0.0177 g·mL-1, 0.0207 g·mL-1, 0.0305g·mL-1, and 0.0623 g·mL-1, respectively; HCS4 at the concentration of 0.05 g·mL-1, ACS1 at the concentration of 0.08 g·ml-1, and ACS2 at the concentration of 0.2 g·mL-1 showed more significant inhibitory effect on the sporangia germination of P. infestans compared with control. The disease index of potatoes infected with P. infestans, which was treated with HCS4 and ACS1, was lower than that of control, suggesting that these two extracts could effectively inhibit the infection of P. infestans. The extracts of ACS2 and ACS3 had some inhibitory effect, but not significantly.