Effects of Environmental Stresses on the Growth of Arabidopsis thaliana Rosette Leaves

Plant growth is constantly affected by biotic and abiotic stresses, which are especially expressed in plant leaves. Therefore, leaf phenotype is considered to be an important indicator of phenotypic plasticity in plants. The effects of various growth environmental factors on the final size of Arabidopsis thaliana rosette leaves and the number of leaves were analyzed in orthogonal tests using image analysis, and growth curves were estimated statistically. Finally, the optimum growth environment for A. thaliana Col-0 was determined. In this study, temperature, humidity, and light intensity were chosen as factors and studied at the three levels each (temperature: 22 °C, 25 °C, 28 °C; humidity: 50%, 65%, 80%; light intensity: 92 μmol·m⁻²·s⁻¹; 184 μmol·m⁻²·s⁻¹; 278 μmol·m⁻²·s⁻¹). The results showed that light intensity was a major factor in the final leaf size, whereas for the number of plant leaves the most important was temperature. According to the major and minor order of environmental factors, the following scheme appeared to be optimal for A. thaliana growth: temperature 22 °C, humidity 50%, illumination intensity 184 μmol·m⁻²·s⁻¹.