Open top chamber experiment study to assess effects of ground level ozone on local peanut cultivar in Vietnam

A simple portable open top chamber ozone fumigation system was applied to investigate the phytotoxic effects of ground level ozone (O3) on a local peanut cultivar in Vietnam. The system was installed directly in the peanut field at a peri‐urban area of Hanoi. Peanut L14 (Arachis hypogaea L.) was exposed to ozone during the flowering stage for seven hours per day, seven days per week. Five different treatments were used, namely, non‐filtered ambient air as the control, and with 7‐h ozone mean of 32 ppb, 62 ppb, 85 ppb and 113 ppb, respectively. The peanut cultivar was found to be adversely affected by ozone which was shown in a steady reduction in growth related variables (leaf area, plant height, plant dry weight) and yield related parameters (number of pods, number of mature pods, straw and seed yield) with the increased ozone exposure. Flecking (brown spots) of the upper leaf surface, the common visible symptom of ozone exposure, was observed after 10 days of ozone exposure. This simple ozone fumigation system could be used to generate data required for the risk assessment of ambient ozone exposure for the agricultural crops in Vietnam and raise awareness so that necessary policy actions can be taken.