Antifungal activity of extracts from leaves of Myrica rubra

Key words: 
• plant protection /
• Myrica rubra /
• extract /
• myricetin /
• antifungal activity

Abstract: The objective is to test the antifungal activity of extracts from Myrica rubra leaves and myricetin. Based on a preliminary test for inhibition of acetone extracts from leaves of Myrica rubra，the fungi Rhizoctonia solani，Sclerotinia sclerotiorum，Botrytis cinerea，Fusarium graminerum，Valsa mali and Fusarium oxysporum f. vasinfectum were selected and their mycelium growth rate were tested in five concentrations（among 5，10，20，30，40，50，and 60 g·L－1）. Antifungal activity was also tested with pure myricetin acetone solution in five concentrations（among 0.30，0.40，0.50，0.60，0.70，and 0.80 g·L－1）. Results showed that when restraining effect were 50%，concentrations of extracts from leaves of M. rubra were （in g·L－1） R. solani（23.08），S. sclerotiorum（19.85），B. cinerea（25.86），F. graminerum（22.07），V. mali（23.18），and F. oxysporum f. vasinfectum（22.86）. Meanwhile，when inhibition was 50%，concentrations with pure myricetin acetone solution for the same fungi were 0.32，0.33，1.09，0.69，0.34 and 2.09 g·L－1 respectively. A stronger effect of 10 times the diluent from leaves of M. rubra showed a therapeutic action 42.3% and a protective function 45.6% on tomato.［Ch，3 tab. 11 ref.］