Root-applied glycinebetaine decreases nitrate accumulation and improves quality in hydroponically grown lettuce

Leafy vegetables like lettuce (Lactuca sativa L.) naturally have high nitrate content and the European Commission has set maximum level for in lettuce. Glycinebetaine is an organic osmolyte alleviating plant stress, but its role leaf accumulation remains unknown. The uptake of glycinebetaine by roots, potential to regulate improve quality were investigated. Two hydroponic experiments conducted with different application rates (Exp1: 0, 1, 7.5, 15 mM; Exp2: 1 + 10, 4 mM). Plants analyzed at varying time points. Root resulted translocation leaves. concentrations > 7.5 mM reduced up 40% increased dry matter content. showed a positive effect on mineral amino acid composition. Thus, could be novel strategy reduce