低温胁迫下外源CaCl2对玉米种子萌发及幼苗生长的影响

以杂C-546为试材,采用10、20、40、80、160 mmol/L外源CaCl_2浸种和叶面喷施不同浓度处理种子,比较分析低温胁迫下玉米种子发芽率、发芽势、发芽指数和幼苗叶片相对电导率、可溶性蛋白、Pn、Fv/Fm、POD和SOD活性等生理生化指标的变化。结果表明,在低温抑制玉米幼苗生长条件下,一定浓度CaCl_2(10~80 mmol/L)处理可降低玉米幼苗生长伤害程度。80 mmol/L CaCl_2浸种处理对玉米低温胁迫的缓解效果最佳,与对照比较,发芽率提高8%,发芽势提高24.6%,发芽指数提高33.2,相对电导率降低51.8%,可溶性蛋白含量增加76.3%,SOD活性增加35.7%。适宜浓度的CaCl_2在低温条件下可促进玉米种子的萌发,降低低温对玉米幼苗造成的伤害。

Effects of Exogenous CaCl2 on Maize Seed Germination and Seeding Growth under Low Temperature Stress

Mixed C-546 maize seeds was used as the experiment material, CaCl₂ were soaked and sprayed at the concentration of 10, 20, 40, 80 and 160 mmol/L separately on maize seed germination and seedling growth under low temperature stress to study changes of germination(Germination rate, germination potential, germination index) and physiological and biochemical indexes(relative electric conductivity, Soluble protein, P_n, F_v/F_m, POD and SOD activity). The results showed that under the condition of low temperature, a certain concentration of CaCl₂ (10-80 mmol/L) can be reduced the extent of maize seedling growth injury, with the concentration of 80mmol/L soaking treatment having the best effect. Under low temperature conditions, exogenous CaCl₂ of 80mmol/L increased germination rate by 8%, germination potential by 24.6%,germination index by 33.2,respectively;reduced the relative electric conductivity by 51.8%, increased the soluble protein content by 76.3%,increased the SOD activity by 35.7%. However, high concentration CaCl₂(160 mmol/L) had lower effects in relieving the growth inhibition. In conclusion, exogenous CaCl₂ of appropriate concentrations can promote the germination of maize seeds, reduce the damage caused by low temperature stress on maize seedlings.