Effect of NaCl and harvest time on antioxidant compounds and morphological cell changes in Lollo Bionda and Lollo Rosso lettuces

It is known that lettuce (Lactuca sativa L. var. crispa L.) phenological stage and environmental changes can cause in the plant cell morphology an important variation secondary metabolites. Antioxidant compounds are beneficial to health salinity increase them. The aim of this study was determine effect salt concentration (NaCl 0.05 0.1 mol L-1) harvest time (days 10, 20 30) on mass, color parameters, antioxidant proline as well morphological tissue two cultivars: Lollo Bionda ‘Levistro’ (green leaves) Rosso ‘Carmoli’ (red leaves). NaCl treatments affected fresh matter (FM), DM DM%, total phenol content, anthocyanin capacity both cultivars. High concentrations decreased FM (from 16.8 8.7 g 3rd harvest) intracellular space leaf but increased 19.6 292.2 μg 100 g-1 ‘Levistro’) 412.9 487.3 mg Trolox eq. ‘Levistro’). In addition, 458.2 506.4 density were significantly higher late than early harvested plants. Thus, successive harvesting may lead capacities lettuces leaves. A moderate decline FM, a indicate better adaptability stress red green lettuces.