Elevated ozone effects on potato leaf physiology, growth, and yield: a meta-analysis.

Potato is an important crop worldwide and threatened by various environmental stresses, including elevated ozone (e[O 3 ]). Here, we conducted a meta-analysis to quantify the effect of e[O 3 ] on potato plants and how it varies depending upon different experimental conditions. Regarding plant growth and biomass, e[O 3 ] significantly decreased shoot biomass by 18% and belowground biomass by 35%, while it increased the leaf area index by 19% and total number of injured leaves by 146%. As for yield, e[O 3 ] significantly decreased the total tuber number by 21%. A relatively pronounced effect of e[O 3 ] on the stomatal conductance was observed when exposure lasted 31-60 days, which was significantly greater than that after exposure lasted 96-311 days. The overall quantity of leaves was mainly decreased by higher (100-150 ppb) than lower (30-80 ppb) concentrations of e[O 3 ] compared to ambient O 3 . The effect of e[O 3 ] on the total tuber number was significant mainly when exposure lasted 31-90 days and was greater in plants grown in growth chambers than those planted in open-top chambers and glasshouses. The effect of e[O 3 ] stress on physiology, growth, and yield varied among cultivars, with some cultivars showing marked tolerance relative to other cultivars. The findings can guide strategies to manage the negative impacts of e[O 3 ] stress on potato production.