铝胁迫对入侵植物北美车前生长特性和生物量分配的影响

Effects of aluminum stress on growth characteristics and biomass allocation of Plantago virginica

关键词:  铝胁迫  生长特性  生物量分配  北美车前

Key words:  aluminum stress  growth characteristics  biomass allocation  Plantago virginica

摘要:

探讨了铝胁迫对入侵植物北美车前生长特性和生物量分配的影响。结果表明：低浓度（ 100 mg/L）的铝胁迫处理对北美车前的生长无显著影响，高浓度（2 000 mg/L）使植株叶片数减少、叶面积变小；短时间高浓度铝胁迫促进北美车前的抽穗数，长时间（30 d）铝胁迫处理后穗生长受到抑制，这种抑制作用在高浓度铝胁迫处理下表现尤其明显。随着铝胁迫程度的加剧，生物量分配存在由地下部转移至地上部的趋势。北美车前在高浓度铝胁迫下形成一种“集中抽穗”模式，这可能是其在生存过程中对不利环境的一种适应行为。

Abstract:

The objective of the present investigation is to observe the effects of different Al3+ concentration (100，500，800，2 000 mg/L) along with different duration times (10，20，30 d) on growth characteristics and biomass allocation of the invasive plant P.virginica. The results showed that 100 mg/L of Al3+ had little effect on the growth of P.virginica. Under 2 000 mg/L of Al3+，both leaf areas and leaf numbers of P.virginica decreased. Spike number of P.virginica was promoted under 2 000 mg/L Al3+ stress for a short treatment time，but its growth velocity was inhibited over a long period 2 000 mg/L. With aggravating Al3+ stress，a trend was found that its biomass allocation prefered aboveground to underground. The proportion of its spikes increased rapidly to a peak and then declined rapidly over the subsequent days under high concentration of Al3+，revealing an adaptive strategy for its reproducing during unfavorable circumstances.