Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 6/5/2007
Publication Date: 7/9/2007
Citation: Li, S., Zhang, S., Lui, Z., Tabanca, N., Wedge, D.E. 2007. In Vitro Assessment of Plant Essential Oils Inhibitory Against Phomopsis Longicolla, the Fungus That Causes Soybean Seed Decay. American Phytopathological Society Annual Meeting. 97:S64. Interpretive Summary:
Technical Abstract: Phomopsis longicolla is a major cause of soybean seed decay. This disease is endemic throughout most soybean-growing states and causes poor quality of soybean seeds in the United States, especially in the mid-southern USA. As part of our effort to screen potential natural fungicides against this pathogen, essential oils from 18 different plant species originally from ten countries were collected and tested for their effects on the growth of P. longicolla in vitro. Based on the daily measurement of fungal radial growth over a 4-day period, all oil samples inhibited P. longicolla when five microliters were tested on potato dextrose agar in 9-cm-diameter Petri dishes. The area under mycelial growth curve ranged from 0 to 69 for treated samples while the untreated control was 114. Reduction of fungal growth ranged from 39 to 100%. Seven plant essential oils that completely inhibited P. longicolla growth were identified. Further experiments will be conducted to analyze the chemical composition of those oils and evaluate their inhibition to other soybean pathogens.