W. Kaewduangta1*, W. Sutthisa2, M. Nakornriab3
and P. Rermkratog1

1Department of Agricultural Technology, Faculty of Technology, Mahasarakham University, Mahasarakham 44150, Thailand.
2 Department of Biology, Faculty of Science, Mahasarakham University, Mahasarakham 44150, Thailand.
3Department of Chemistry, Faculty of Science, Mahasarakham University, Mahasarakham 44150, Thailand.

Abstract

The effect of crude extracted and essential oils was comparedfor controlling anthracnose disease in Dendrobium ‘Earsakul’.Dendrobium ‘Earsakul’ was tested to determine the efficiency of five Thai medicinal herbs: galangal, garlic, lemongrass, turmeric and ginger on the growth inhibition of Colletotrichumsp. as the pathogens ofanthracnoseor leaf blight disease.Each medicinalplant was blended and macerated in 95% ethyl alcohol and sterile distilled water at ratio 200 g: 400 mL for seven days. Crude extracts and essential oil were tested for inhibition of their antifungal potentials against Colletotrichum sp. by food poison technique.Results in the laboratory and under greenhouse condition showed that 8,000 ppm essentialoilof ginger inhibited the growth of Colletotrichumsp.both before and after disease infection at 100% similarwith the chemical compound Mancozeb.

Keywords: Dendrobium ‘Earsakul’,plant extract,essential oil,Thai medicinal herb,Colletotrichum sp.