Screening of Plant Extracts for Fungicidal Activities on Large Patch Pathogen

Jae-Gyeong  Jung1   Eun-Ji Bae1,*    Jun-Hyuck Yoon1   Eon-Ju Jin1   Kwon-Seok Jeon1   

1Forest Biomaterials Research Center, National Institute of Forest Science, JinJu 52817, Korea


For natural turfgrass school grounds, the public tends to object to using chemical control due to negative perceptions about the use of chemical disinfectants and human safety issues when a problem occurs due to disease, which is one of the issues pointed out as difficulties in lawn management on natural grass school grounds. In addition, the need to develop organic materials for eco-friendly lawn management is emerging under the recent sentiment of growing interest in eco-friendliness. This study performed the disk diffusion test and mycelium growth inhibitory assay on the large patch (Rhizoctonia solani AG2-2), which is the most troubling for zoysiagrass, to develop eco-friendly management technology for natural turfgrass school grounds. Plant-derived natural products were quantified at a concentration of 1 µg µL-1 in a total of 110 extracts separated by methanol and hot water extraction method for 55 species of leaves, including Hydrangea macrophylla. Based on a comprehensive judgment of the two experimental results, eight plant extracts, including Hydrangea macrophylla, Ficus carica, Punica granatum, Citrus junos, Citrus reticulata, Pueraria lobata;, Campsis grandiflora, and Kalopanax septemlobus, were determined to reduce large patch pathogens significantly. As a secondary test, the eight tree species selected above were increased in concentration from 20 µg to 2 mg, which was 100 times higher than extract concentrations used in the conventional disk diffusion method. The Ficus carica suppressed the extending growth of mycelium in the same manner as the pathogen growth inhibition seen in the control fungicide (Tebuconazole). These results identified the possibility of Ficus carica as a biological pesticide, with subsequent plans to confirm and test further feasibilities through additional in-situ experiments.

Figures & Tables

Fig. 1. Antifungal activity of crude plant extracts against AG2-2 by paper disc assay in vitro. ns: Non-significant; +: Doubtful effect; ++: Poor effect; +++: Moderate effect; DMSO: Dimethylsulfoxide.