Fig. 1

Effects of prolonged UV-B stress on Nβ and Sβ seedlings. A Photographs of the shoots (upper panel) and roots (lower panel) of Nβ and Sβ plants under non-stress and after 5-day-long (6 h/day) UV-B stress. B Shoot length, C root length, D plant biomass represented in g FW/plant, and E relative water contents from the leaves of Nβ and Sβ seedlings under non-stress and stress conditions were subsequently measured for growth performance. The means with different letters are significantly different (P < 0.05) within the same treatment (Nβ^ns vs. Sβ^ns and Nβ^uvs vs. Sβ^uvs). Lines with asterisks indicate significant differences between non-stress and UV-B stress conditions of the same plants (Nβ^ns vs. Nβ^uvs and Sβ^ns vs. Sβ^uvs), as determined by Student’s t test (*P < 0.05, **P < 0.01)