CAJ | 학술논문

为了解镉胁迫下外源钙对白菜生理响应的调控机制，通过水培实验研究了在Cd（100μmol·L-1）胁迫下Ca（5 mmol·L-1）对白菜（Brassica pekinensis）叶片钙离子和镉离子含量、ROS和MDA含量、抗氧化酶活性、还原性谷胱甘肽和内源NO含量变化的影响，并使用0.2 mmol·L-1的三氟拉嗪（TFP）研究了Ca2+-CaM信号在其中的转导功能。结果表明：（1）Cd胁迫降低了白菜叶片的Ca含量，而外源Ca增加了Ca含量并降低Cd含量，但TFP对叶片Ca、Cd含量无明显影响；（2）Cd诱导白菜叶片ROS爆发，引起质膜过氧化，并抑制了SOD活性，提高了APX、CAT和POD活性及GSH含量，增加了叶片过氧化压力，施加外源钙后降低了这种压力，而TFP的加入却降低了这种缓解作用；（3）Cd抑制了叶片NO含量，补充外源钙后提高了NO含量，而TFP降低了外源钙对NO的上调。研究可知，外源钙能降低白菜叶片Cd含量，增强Ca含量，并通过Ca2+-CaM信号途径调节抗氧化酶和GSH含量，维持叶片ROS平衡，提高叶片内源NO的表达，从而增强白菜Cd的耐性。
위료해력협박하외원개대백채생리향응적조공궤제，통과수배실험연구료재Cd（100μmol·L-1）협박하Ca（5 mmol·L-1）대백채（Brassica pekinensis）협편개리자화력리자함량、ROS화MDA함량、항양화매활성、환원성곡광감태화내원NO함량변화적영향，병사용0.2 mmol·L-1적삼불랍진（TFP）연구료Ca2+-CaM신호재기중적전도공능。결과표명：（1）Cd협박강저료백채협편적Ca함량，이외원Ca증가료Ca함량병강저Cd함량，단TFP대협편Ca、Cd함량무명현영향；（2）Cd유도백채협편ROS폭발，인기질막과양화，병억제료SOD활성，제고료APX、CAT화POD활성급GSH함량，증가료협편과양화압력，시가외원개후강저료저충압력，이TFP적가입각강저료저충완해작용；（3）Cd억제료협편NO함량，보충외원개후제고료NO함량，이TFP강저료외원개대NO적상조。연구가지，외원개능강저백채협편Cd함량，증강Ca함량，병통과Ca2+-CaM신호도경조절항양화매화GSH함량，유지협편ROS평형，제고협편내원NO적표체，종이증강백채Cd적내성。
Calcium can alleviate heavy metal stresses in plants. A hydroponic experiment was conducted to investigate the physiological mechanisms of Chinese cabbage(Brassuca pekinensis)responses to cadmium(Cd)stress under exogenous calcium(Ca). Concentrations of Ca and Cd ions, reactive oxygen species(ROS), malondialdehyde(MDA), glutathione, and endogenous nitric oxide(NO)as well as antioxi-dant enzymatic activities in cabbage leaves were determined. Meanwhile, the transduction function of Ca2+-CaM influenced by Trifluoper-azine(TFP, 0.2 mmol·L-1)was also investigated. Cadmium stress decreased Ca concentrations in cabbage leaves, while exogenous Ca addi-tion increased Ca but decreased Cd concentrations in the leaves. However, TFP had no significant effects on the concentrations of Ca and Cd. Cadmium induced ROS outburst in cabbage leaves, resulting in the peroxidation of plasmalemma and also suppressed superoxide dis-mutase(SOD)activity. However Cd increased the activities of ascorbate peroxidase(APX), catalase(CAT), and peroxidase(POD)and the concentration of clutathione(GSH), causing an escalated peroxide pressure in cabbage leaves. Exogenous Ca addition alleviated Cd induced pressure, but such alleviating effect was weakened by TFP addition. Nitric oxide concentrations in cabbage leaves were reduced by Cd but increased by exogenous Ca. This boosting effect of Ca was depressed by TFP addition. These results suggest that exogenous Ca reduces the Cd stress in cabbage leaves through decreasing Cd uptake and increasing antioxidant capability by Ca2+-CaM signal pathway.