Response of different agricultural plants to elevated CO2 and air temperature

Abstract

The aim of this study was to estimate the response of different agricultural plants to elevated CO2 and temperature and to check a hypothesis that current ambient CO2 concentration is a limiting factor for growth of most agricultural species. Experiments were conducted in the chambers with a controlled climate. Seven most common agricultural crops and one weed species fat hen (Chenopodium album L.) were selected for the investigation. Dry over-ground biomass, concentration of chlorophylls and carotenoids were evaluated at the end of the experiments. The over-ground biomass of all investigated species significantly increased along with an increase in CO2 concentrations and for most species the greatest biomass accumulation was observed at 700–1500 ppm. Response of fat hen biomass accumulation to elevated CO2 concentration was comparatively small and statistically insignificant, indicating that for this species current CO2 concentration is not a limiting factor. Analysis of the results on integrated impact of elevated CO2 (700 ppm) and temperature (+4ºC) on the growth of investigated plants showed that the plant response is highly species specific. Tomato and soybean, which are considered the greatest warmth-loving plants under local climate conditions, produced the highest amount of biomass at elevated both CO2 and temperature. For other investigated species, no positive interaction between CO2 and temperature was detected and differences in biomass formation under elevated CO2 alone and elevated both CO2 and temperature ere not statistically significant.