Influence of white clover mosaic potexvirus infection on the endogenous levels of jasmonic acid and related compounds in Phaseolus vulgaris L. seedlings

Primary leaves of 16-day-old Phaseolus vulgaris L, seedlings were inoculate d with either white clover mosaic potexvirus (WClMV) or water. The concentr ations of jasmonic acid (JA), dihydrojasmonic acid (DHJA) and cucurbic acid (CA), and virus titre were measured over a ten day period following inocul ation. A transient increase in the concentration of JA occurred immediately following inoculation with water or WClMV, which we attribute to wounding. A second increase in JA occurred only in virus-infected leaves. Concentrat ions of cucurbic and dihydrojasmonic acids were not affected by wounding, b ut virus-infection resulted in a decline in the concentration of CA and an increase in DHJA. Reasons for the changes in jasmonate concentrations after virus infection are discussed.