Inhibition of Growth in Tomato by Air Polluted with Nitrogen Oxides

Air polluted with parts 10_–8concentrations of NO and NO₂significantly reduced the rate of growth of tomato seedlings.These two pollutants are known to occur in glasshouse atmos-Dhcresenriched with CO² from propane or kerosene burners. The inhibitionof growth would be sufficient to reduce, or even nullity, thebenefits of CO₂enrichments under conditions of low light intensityin winter.