Abstract
The acoustic emission (AE) was measured for 25 days on a stem of a miniature tomato while applying loading and unloading by an electric actuator. The sensor attached on the stem applying the loading and unloading detected more AEs than the other. Moreover, the number of AE events was often rapidly increased just after applying the loading and unloading to the stem. These results showed the possibility of the induced cavitations in the stem by the loading and unloading. Number of AE events was increased on the dark period as well as the light period by applying the loading and unloading. In addition, the number of AE events of the dark period was increased with the increase in drought stress. However, the correlation between the drought stress and the ratio of AE occurrence rate due to the loading and unloading was not found. The influence of the loading and unloading on the AE occurrence behavior, therefore, might be longer than the interval of loading and unloading.
