Figure 5

Ion accumulation and photosynthetic quantum yield ΦPSII in SAPK4 -over-expressing rice in response to salt stress. (A) Reduced Cl^- content in leaves of 8-week-old SAPK4-over-expressing lines S1 and S4 treated with 150 mM NaCl for 48 h compared with wild-type rice grown under control conditions and salt stress. Values are means ± S.D. (n = 30). (B) Na⁺, K⁺ and Ca²⁺ content in leaves of wild-type rice and the SAPK4-over-expressing line S4. The plants were grown in hydroponic culture to the age of 3 weeks and were treated with 150 mM NaCl for 48 h. Values are means ± S.D. (n = 7). (C) ΦPSII was calculated from chlorophyll a fluorescence. The measurements were performed in attached leaves of 8-week-old control plants and plants treated with 150 mM NaCl for 48 h. Data represent means ± S.D. n = 30.