Air circulation in growth chambers stunts tomato seedling growth

Air circulation, generally an integral part of environmentally controlled plant growth chambers, inhibited tomato (Lycopersicon esculentum Mill.) seedling growth seismomorphogenically. Tomato seedlings were grown either in a growth chamber having an air movement of 0.5–0.7 m s −1 or in a chamber with no air circulation. Growth inhibition was noticeable with as little as 15 min of daily exposure to air circulation, and a continuous exposure gave the greatest amount of growth inhibition. The air-movement effect on seedling growth was transient and required a continued daily exposure to air movement for growth inhibition. Continuous air circulation inhibited seedling growth to such an extent that in a two-factor experiment (i.e., air movement and water stress) the water-stress effects were completely hidden by the air-movement effect. The results have important implications for tomato plant growth experiments in chambers equipped with air circulation: seedling growth may be affected more by the inherent air circulation in the growth chamber than by an experimental treatment.Key words: Tomato growth inhibition, air movement, seismomorphogenic, short seedlings