Cheng Yu-Jie, Deng Xi-Ping, Kwak Sang-Soo, Chen Wei, Eneji Anthony E
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Department of Forest, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Bot Stud. 2013 Dec;54(1):30. doi: 10.1186/1999-3110-54-30. Epub 2013 Sep 3.
Glycinebetaine, whose biosynthesis could be catalyzed by choline oxidase (COD), is an extremely efficient compatible solute for scavenging oxidative stress-inducing molecules and protecting the photosynthetic system in plants. To study the effects of the codA transgene for choline oxidase on the drought resistance and recovery, a transgenic potato cultivar (SC) bearing codA gene and a non-transgenic (NT) control cultivar were raised in pots under moderate and severe drought stress. The experiment was constituted by a two-day-pretreatment with 20% PEG and a four-day-water stress combined with two-day-recovery treatment.
Under the four-day-water stress, plants were provided with normal water condition, 10% or 20% polyethylene glycol. The results of pretreatment showed an expression of codA gene in transgenic potato and an accumulation of glycine betaine (GB); leaf water potential was higher in SC than in NT. In the stress-recovery-treatment, SC showed stronger antioxidant ability, more efficient photosynthetic system, higher chlorophyll content, lower malondialdehyde content and better recovery from water deficit stress than NT.
Although this work concentrated on the short-term water stress and recover treatments on transgenic potato plants with the over-expression of CodA gene and its control line. The datas shows that the exogenous codA gene provided potato a stronger drought resistance and recovery ability.
甘氨酸甜菜碱可由胆碱氧化酶（COD）催化生物合成，是一种极其有效的相容性溶质，可清除诱导氧化应激的分子并保护植物的光合系统。为了研究胆碱氧化酶的codA转基因对耐旱性和恢复能力的影响，将携带codA基因的转基因马铃薯品种（SC）和非转基因（NT）对照品种种植在花盆中，施加中度和重度干旱胁迫。实验由20%聚乙二醇预处理两天、四天水分胁迫以及两天恢复处理组成。
在四天水分胁迫期间，为植株提供正常水分条件、10%或20%的聚乙二醇。预处理结果显示转基因马铃薯中codA基因表达且甘氨酸甜菜碱（GB）积累；SC的叶片水势高于NT。在胁迫恢复处理中，SC比NT表现出更强的抗氧化能力、更高效的光合系统、更高的叶绿素含量、更低的丙二醛含量以及从水分亏缺胁迫中更好的恢复能力。
尽管这项工作集中于对过表达CodA基因的转基因马铃薯植株及其对照品系进行短期水分胁迫和恢复处理。数据表明外源codA基因赋予马铃薯更强的抗旱性和恢复能力。
