渗透胁迫与大豆幼苗类囊体膜上结合态亚精胺的关系

Relationship between Osmotic Stress and Conjugated Spermidine in the Thylakoid Membrane of Wheat Seedling

研究了渗透胁迫下,大豆品种豫豆24号(抗旱性较强)和豫豆6号(抗旱性较弱)幼苗类囊体膜上非共价结合态亚精胺(NCC-Spd)和高氯酸不溶性共价结合态亚精胺(PISCC-Spd)含量的变化。结果表明,渗透胁迫下,抗旱性弱的豫豆6号的NCC-Spd和PISCC-Spd下降幅度明显大于抗旱性强的豫豆24号;外源Spd处理明显抑制了渗透胁迫下豫豆6号类囊体膜上NCC-Spd含量的下降,也提高了豫豆6号大豆幼苗的抗性;Spd生物合成的专一性抑制剂——MGBG处理,则明显促进了渗透胁迫下豫豆24号类囊体膜上NCC-Spd含量的下降,也降低了豫豆24号大豆幼苗的抗性;PISCC-Spd生物合成的专一性抑制剂——o-phen处理,促进了渗透胁迫下大豆幼苗类囊体膜上PISCC-Spd含量的下降,而且明显降低了大豆幼苗的抗性。表明大豆幼苗类囊体膜上NCC-Spd和PISCC-Spd水平在胁迫条件下的稳定有利于增强大豆幼苗适应渗透胁迫的能力。

The changes in contents of noncovalently conjngated-spermidine （NCC-Spd）and perchloric acid insoluble covalently conjngated-spermidine （ PISCC- Spd） to thylakoid membrane were investigated in seedling leaf of two soybean （Glyeine. max L. ） cultivars, Yudou 24 （ drought-tolerant ） and Yudou 6 （drought-sensitive） under osmotic stress. On the 7th day, after polyethylene glycol （PEG） -6,000 treatment, the contents of NCC-Spd and PISCC-Spd were decreased more significantly in Yudou 6 than in Yudou 24.Under osmotic stress,exogenous Spd treatment resulted in inhibiting the decrease in NCC- Spd level in Yudou 6 and in enhancing its tolerance to stress.Treatment with ethylglyoxal-bis （guanylhydrazone） （MGBG） ,which was an inhibitor of Spd biosynthesis,resulted in enhancing the decreasing in NCC-Spd level in Yudou 24 and in the decreasing of its tolerance to stress.Treatment with o-phen, which was an inhibitor of PISCC-Spd biosynthesis,resulted in enhancing the decreasing of PISCC-Spd and in decreasing of the tolerance of seedlings to stress.The results suggested that the content steadiness of NCC-Spd and PISCC-Spd in thylakoid membrane enhanced the adaptation of soybean seedlings to osmotic stress.