NaCl胁迫对黑小麦根系DNA损伤的影响

Effects of NaCl stress on root DNA damage of black kernel wheat

【目的】探究氯化钠(NaCl)胁迫对黑小麦根系DNA损伤的影响,为寻求减轻环境因子对植物DNA损伤的方法及培育耐盐黑小麦品种提供参考。【方法】以黑小麦品种漯珍1号为材料,采用5个NaCl质量浓度(0、3、6、9、12和15g/L)溶液处理黑小麦幼苗根系,通过彗星电泳试验,利用CASP 1.2.2分析代表黑小麦幼苗根系DNA损伤的尾部DNA含量、尾长和尾矩等指标。【结果】随着NaCl质量浓度的增加,彗星头部渐小,拖尾渐长,黑小麦根系DNA损伤片断的迁移水平逐步上升。尾部DNA含量、尾长和尾矩均随着NaCl质量浓度的增加呈升高趋势,在15 g/L处理下,三者的升幅分别达67.56%、139.40%和39.88%。随着NaCl质量浓度的增加,Olive尾矩(OTM)均有提高,但增长率慢慢下降,12~15 g/L的增长率降至5.42%,说明黑小麦具有一定的耐盐性。【结论】NaCl胁迫会引起黑小麦根系DNA损伤,且受损程度随着NaCl质量浓度的增加而愈发严重,但黑小麦对NaCl胁迫仍存在一定抗性。

【Objective】Effects of sodium chloride(NaCl)stress on root DNA damage of black kernel wheat were explored in order to provide an important theoretical reference for finding a way to reduce the damage of environmental factors to plant DNA and salt tolerant black kernel wheat varieties breeding.【Method】Using black kernel wheat(Luozhen No.1)as the materials,five NaCl mass concentrations(0,3,6,9,12 and 15 g/L)were set for black kernel wheat root treatment. This research was studied by comet assay. Indexes representing root DNA damage of black kernel wheat,such as tail DNA content,tail length and tail moment,were analyzed using CASP software.【Result】The comet head was gradually becoming small and trailing gradually extended as NaCl concentration aggravated. Furthermore,the migration level of DNA damage fragments in the root increased. Tail DNA content,tail length and tail moment increased with the augment of NaCl concentration. Under 15 g/L treatment,the increases of tail DNA content,tail length and tail moment each were67.56%,139.40% and 39.88%. With the increase of NaCl mass concentration,Olive tail moment(OTM)values increased but the increasing rate slowly declined,even fell to 5.42% between 12 g/L and 15 g/L concentration,indicating that black kernel wheat had certain salt tolerance.【Conclusion】NaCl stress causes root DNA damage of black kernel wheat,and DNA damage enhances as the NaCl mass concentration increases,but black kernel wheat still has certain resistance to NaCl stress.