摘要
通过对67个玉米品种幼苗在—6.2巴水分胁迫条件下生理生化变化的研究证明:水分胁迫时,玉米幼苗叶片的水势下降、电解质渗漏率增加、脯氨酸含量增加,抗坏血酸含量减少。并且在一定水势以下,电解质渗漏率、脯氨酸变化率对数、抗坏血酸变化率均与水势在极显著水平相关。因此我们认为三者是玉米幼苗抗旱性的较好指标。随着水势的下降,三者都有一个发生变化的临界点,该点水势分别为:抗坏血酸为—8巴,电解质渗漏率为—9巴,脯氨酸为—10巴。这说明干旱对植株的损伤顺序为:活性氧增加,抗氧化剂减少,生物膜损伤;代谢发生调整。同时也说明三个指标对干旱的敏感性为:抗坏血酸>电解质渗漏率>脯氨酸。
67 varieties of maize sccdlings were investigated in—6.2 bar. The changes of biochemistry physiology indicated that electrolytes leakage and prolinc inercased, yet ascorbic acid deercased as warter stressed. Below a certain warter potential, electrolytes leakage, logarithm of change rate of prolinc content, changc rate of ascorbic acid content were closely corrclation with wartcr potential. So we suggested that the three indices were better for drought-resistance in maize seedlings. As warter potential reduced, there were critical poonts in these indices. The warter potential at the critical points of electrolytes lcakage, ascorbic acid and prolinc were—9 bar,—8 bar and—10 bar respcetively, which indicated that scqucncl of drought injury to plant was that active oxygen incrcased and its antioxidants deercased, biomembrane damaged and mctabolice disorder. The sequence of drought sensetive of these indices was ascorbic acid, electrolytes lcakage, prolinc.
关键词
水势
脯氨酸
抗旱性
玉米
warter potential, ascorbic acid, clectrolytes leakage, proline, drought—reistance.
