Lack of trichomes and variation in stomata properties influence the quantum efficiency of photosynthesis in Arabidopsis

This study investigates how the absence of trichomes and variations in stomatal properties affect the quantum efficiency of photosynthesis in Arabidopsis thaliana during drought stress. We analyzed three genotypes: Col-8 (with trichomes and lower stomatal density), epf1epf2 (with higher stomatal density), and tmm-1 (lacking trichomes and altered stomatal characteristics) to determine the influence of these anatomical traits on photosynthetic performance. Under well-watered conditions, epf1epf2 and tmm-1 exhibited higher photosynthetic efficiency (Fv´/Fm´) compared to Col-8. During drought stress, Col-8 maintained stable Fv´/Fm´, while epf1epf2 and tmm-1 experienced significant reductions. Our findings indicate that the presence of trichomes and higher stomatal density positively impacts photosynthetic efficiency under optimal watering while the presence of trichomes becomes less crucial under drought stress. Efficient adjustment of stomatal density and size under drought conditions plays a more significant role. These insights emphasize the importance of considering anatomical traits in breeding programs to enhance drought resistance and photosynthetic performance in plants. • Trichomes and stomatal density were studied in relation to drought stress in Arabidopsis. • Col-8 plants maintained photosynthetic efficiency by increasing stomatal density under drought. • epf1pef2 and t mm-1 , with higher stomta density than Col-8, showed reduced stomata density and photosynthesis efficiency. • Trichomes did not significantly contribute to photosynthesis effiecieny in Arabidopsis. • Variation in stomatal density, not merely the stomata density, influenced photosynthetic performance.