effects of co2 and light regimes on anatomical and physiological traits on three cultivars of pansy (viola tricolor) in greenhouse

in one side the negative effects of increasing of concentration of carbon dioxide in the world, and in the other side, the positive effects of greenhouse enrichment by such gas is one of the most important reasons in researching of this gas on different plants. for assessment of the effects of carbon dioxide and light regimes in different genotypes of pansy (viola tricolor) a factorial experiment based on completely randomized design with 3 replications and 18 treatments was conducted at the greenhouses of ferdowsi university of mashhad at 2009. the treatments are including; 2 concentrations of carbon dioxide (380 and 1000 µmol/mol), 3 light regimes (11000 and 14000 lux and sun light) and 3 cultivars (yellow-black, bourdeaux, sawyers-black) of pansy. the results of this experiment showed that among the 11 measured traits in the most treatments, the traits of length, width and the number of stomata and dry weight of shoot were significant. the concentration of 1000 µmol/mol carbon dioxide had less decreasing of stomata conductivity and dry weight than carbon dioxide 380 µmol/mol. totally the effect of light regimes on the measured traits didn’t has any significantly difference with sun light. among the cultivars, altogether sawyers was more proper because of less stomata conductivity and probably decreasing of water consumption.