Seedlings of trembling aspen (Populus tremuloides Michx.) were grown at six rates of supplemental nitrogen (N). Five of the N rates were sub‐optimal to optimal for growth, whilst the sixth provided an excess of N with no additional growth benefit. The biomass of plants stressed by ozone (O3) in open‐top chambers was significantly reduced at optimal rates of N. Plants which received sub‐optimal or excess N showed no significant effects of O3 on biomass accumulation. Ozone induced two compensatory responses; increased shoot/root ratio and accelerated senescence, at all N rates. Growth rate was strongly influenced by the amount of N supplied, and O3‐induced reductions in total biomass were highly correlated with growth rate. We concluded that when growth rate was small as a result of N limitation, compensatory responses to O3 stress were sufficient to prevent detectable losses in biomass.
|Original language||English (US)|
|Number of pages||10|
|State||Published - Jul 1995|
All Science Journal Classification (ASJC) codes
- Plant Science