Two drought-tolerant transgenic rice lines, L-8 (single copy) and L-23 (two copy), expressing the Capsicum annuum methionine sulfoxide reductase B2 (CaMsrB2) gene were selected for stress tolerance phenotyping under drought stress conditions. | Turkish Journal of Botany Research Article Turk J Bot (2015) 39: 973-981 © TÜBİTAK doi: Field assessment of CaMsrB2 transgenic lines in a drought stress environment Zamin Shaheed SIDDIQUI1,*,**, Jung-Il CHO2,** , Dan-Be PARK2, Gang-Seob LEE2, Tae-Hun RYU2, Huda SHAHID1, Muhammad UMAR1, Soo-Chul PARK2 1 Stress Physiology Phenotyping Laboratory, Department of Botany, University of Karachi, Karachi, Pakistan 2 National Academy of Agricultural Science, Rural Development Administration, Suwon, Republic of Korea Received: Accepted/Published Online: Printed: Abstract: Two drought-tolerant transgenic rice lines, L-8 (single copy) and L-23 (two copy), expressing the Capsicum annuum methionine sulfoxide reductase B2 (CaMsrB2) gene were selected for stress tolerance phenotyping under drought stress conditions. The two transgenic lines were selected on the basis of laboratory experiments and for performing well against drought. Field assessment of CaMsrB2 transgenic lines L-23 and L-8 in a drought stress environment was conducted. For the assessments, small plots were prepared at the Department of Botany of the University of Karachi to test the physiological response of transgenic lines. Relative water content, quantum yield (Fv/Fm ratio), photochemical quenching (qP) photosynthetic pigments, and performance index were high in transgenic lines compared to the wild type (WT). Antioxidant enzymes as represented by catalase and superoxide dismutase activities were increased while H2O2 production was decreased in transgenic lines compared to the WT. The results are discussed with special reference to physiological response of the transgenic lines against drought in field conditions. Key words: CaMsrB2, L-23 lines, rice, drought, field 1. Introduction Drought and salinity have long been known to be the most prevalent abiotic stresses in arid and semiarid regions, restraining growth and
