干旱胁迫下早熟禾幼苗几种抗旱性指标的变化

[目的]探明干旱胁迫下早熟禾幼苗几种抗旱指标的变化规律。[方法]在干旱胁迫期间对早熟禾幼苗植株体内过氧化物酶活性、脯氨酸含量、丙二醛(MDA)含量的变化进行了研究。[结果]在干旱胁迫后期,早熟禾幼苗植株体内过氧化物酶活性、脯氨酸含量均有较高水平增加,有利于其抵抗干旱胁迫。在土壤含水量未达到5.4%前,MDA的含量无显著差异(P>0.05),膜伤害较小;但当土壤含水量降到5.4%时,MDA的含量显著上升。[结论]当土壤含水量降到5.4%时,膜结构遭到破坏,抗逆性下降,是导致早熟禾幼苗干旱死亡的主要原因。

Preliminary Study on the Accumulation Characteristics of Mineral Elements in Potted Poa crymophila under Drought and Water Stress

[Objective] This study was conducted to explain the mechanism of the accumulation characteristics of mineral elements in alpine grassland plants. [Method] Cultivated alpine grassland plant, Poa crymophila, was treated with drought and wa- ter stress, and then the samples were collected and analyzed. [Result] Compared with the control group, under drought and water stress, multiple mineral elements tended to accumulate and increase, and there were significant differences in the contents of Cu, Mn, Ni and P （P〈0.05）. [Conclusion] Under drought and water stress, mineral elements in potted Poa crymophila tended to accumulate and in- crease, which is the adaption and response of Poa crymophila to drought and water stress, as well as the re-verification of the starvation effect hypothesis of mineral effects. The starvation effect of mineral elements is one of the endogenic forces for the accumulation and differentiation of mineral elements in grassland plants.