铅胁迫对豌豆种子的毒害效应

目的]探究铅胁迫对豌豆种子的毒害效应。方法]以豌豆为试验材料,采用水培方法研究铅胁迫对豌豆种子萌发与生长的影响。结果]结果表明,铅浓度小于1 mg/L时,促进种子萌发;铅浓度为1 mg/L时种子的萌发率最高;铅浓度为5 mg/L时抑制豌豆种子萌发;铅浓度≤5 mg/L时促进根、茎的生长,≥10 mg/L时抑制根、茎的生长,并且随着铅离子浓度的增大,抑制作用加强;铅对根的抑制作用大于茎。铅诱发的胚根细胞核、染色体畸变率随着铅浓度的增加而增大。低浓度铅(≤1 mg/L)能促进幼苗叶绿素合成,铅浓度高于1mg/L时,则对幼苗叶绿素合成有抑制作用,且随铅浓度增加叶绿素含量逐渐下降。过氧化物同工酶活性在铅浓度1 mg/L时,稍低于对照;铅浓度为5 mg/L时,过氧化物同工酶活性明显增强。结论]为缓解今后研究铅害机理提供参考数据。

Study on Toxicity Effects of Pb Stress on Pea Seed

Objective] This research aimed to explore the toxicity effects of Pb stress on pea seed.Method] With pea as tested materials,the toxicity effects of Pb on the germination and growth of pea seed were investigated by water culture method.Result] When Pb was less than 1 mg/L it promoted the seed germination.When Pb was 1 mg/L,the germination rate of pea seed was the highest.When Pb concentration was increased to 5 mg/L,the seed germination was inhibited.When Pb was less than or equal to 5 mg/L,it promoted the growth of the root and stem.When Pb was more than or equal to 10 mg/L,it was obviously to inhibit the growing of the root and stem and this inhibition strengthened along with the increasing of the concentration of Pb,with greater inhibition on roots than on stems.The aberration rate of radicle cell nuclear and chromosome induced by Pb was increased with the increasing of the concentration of Pb.The low concentration of Pb(less than or equal to 1 mg/L)could promote the synthesis of chlorophyll.When Pb concentration was over 1 mg/L,it would inhibit the synthesis of chlorophyll in seedling leaves and the chlorophyll content was decreased with the increasing of the concentration of Pb.POD isoenzyme activity was lower than CK when Pb was at 1 mg/L and obviously strengthened when Pb concentration was increased to 5 mg/L.Conclusion] The research provided a reference data for the Pb toxicity mechanism in the future.