干旱胁迫对甘蔗新品种桂热2号生理指标的影响

为探讨甘蔗桂热2号（GR2）对干旱胁迫及外源脱落酸（ABA）的响应机制,以ROC22（抗旱性强）为对照（CK）,采用自然干旱的方式,分析GR2在干旱胁迫不同天数时生理指标的变化特点。结果表明,GR2在干旱胁迫下叶片内源激素含量、抗氧化酶活性及渗透调节物质含量显著提高。与CK相比,GR2在胁迫前期（0~5d）可溶性蛋白和可溶性糖含量增幅相对较大,丙二醛含量相对稳定,胁迫中期（7~9d）ABA、超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）活性增幅相对较大。外源ABA处理能增强GR2内源激素含量的积累能力,提高其抗氧化酶SOD、APX及过氧化物酶活性,有效缓解渗透物质的积累,使其含量处于较低水平。综合表明,GR2是一个抗旱性较强的品种,外源ABA能提高其抗旱能力。

Effects of Drought Stress on Physiological Indexes of New Sugarcane Variety Guire 2

In order to investigate the response mechanism of the sugarcane variety Guire 2 (GR2) to drought stress and exogenous abscisic acid (ABA) with ROC22 as control (CK), the natural drought method was set, the GR2 was used for the change properties of physiological indices under drought stress with different number of days. The results showed that the content of endogenous hormones, the activity of antioxidant enzymes and the content of osmotic substances in the leaves of GR2 were significantly increased under drought stress. Compared with the drought-resistant CK, soluble protein, soluble sugar contents of GR2 were relatively strongly increased in the early period (0-5d), MDA content was relatively stable, the activities of ABA, SOD and APX growth was relatively high in the middle period (7-9d). Exogenous ABA treatment could effectively increase the accumulation of hormone content, the activities of the antioxidant enzymes (SOD, APX and POD), and relieve the accumulation of osmotic substances effectively. It was suggested that GR2 was a variety of sugarcane that has strong drought resistance, and exogenous ABA may improve its ability of drought resistance.