Genotypic Variation for Stomatal Characters and their Physiological Implications in Madagascar Periwinkle (Catharanthus roseus (L) G. Don)
2008
Stomatal characters namely the frequency of stomata, their size, pore dimension as well as stomatal conductance were analysed in white and pink flowered Madagascar periwinkle to record genotypic variation for these parameters. Biomass production in these genotypes simultaneously was estimated to understand the physiological consequences. White genotypes recorded to have significantly more stomata on both the leaf surface than the pink though their stomatal aperture did not significantly differ. However, the pore area per cent in relation to leaf size was higher in the white genotype and simultaneously it recorded increased stomatal conductance. Notwithstanding these stomatal attributes the white produced less biomass and the pink maintained higher biomass turnover with increased leaf area where biomass showed significantly positive correlation with the leaf size. At the same time the pink continued to exhibit relatively less proportionality estimates of stomatal frequency between upper and lower leaf surfaces. The physiological significance of such genotypic variation in terms of drought tolerance and higher photosynthate accumulation was discussed.
显示更多 [+] 显示较少 [-]