Ethylene emission of L. japonicus during interaction with M. loti. Five-day-old plants were inoculated and grown in unsealed glass vials until capping 3 h prior to each measurement point. Measurements were conducted on independent biological replicates at each time and condition for n = 6. Asterisks represent statistical comparison between mock and R7A by t test at each time: *< 0.05, **< 0.01, ***< 0.001.