IMPACT OF AMBIENT AIR ON PHYSIOLOGY, POLLEN TUBE GROWTH, POLLEN GERMINATION AND YIELD IN PEPPER (CAPSICUM ANNUUM L.)

Abstract

Pepper (Capsicum annuum L.) plants were exposed in open top-chambers to non-filtered ambient air (NFAA) and to charcoal filtered air (FA) to study the effect of ambient air on physiological parameters, growth, yield, as well as pollen tube and pollen growth of plants. NFAA caused reductions in net photosynthetic rates (19%), stomatal conductance (26%), yield components (29% and 25% losses in fresh weight and number of fruits/plant, respectively) as well as degradation of epicuticular wax of its leaves. Moreover, pollen collected from plants grown in NFAA showed lower germination rates and reductions in pollen tube length (41 and 10%, respectively). Our results showed that detrimental effects of O3 on reproductive growth and development are compromising current crop yields and the fitness. Fresh weight of pods was reduced by 29% due to exposure to NFAA. The significance of pollutant-induced impairment of pollen germination and growth for reproductive development are discussed. To the best of our knowledge, this is the first report demonstrating the marked reduction in pollen germination rates and pollen tube length and their significance to crop physiology and yield from the environment in the developing world.