Predicted global warming scenarios impact on the mother plant to alter seed dormancy and germination behaviour in Arabidopsis
Predicted global warming scenarios impact on the mother plant to alter seed dormancy and germination behaviour in Arabidopsis
复制标题
DOI：
10.1111/pce.13082
复制
发表时间：
2018-01-01
影响因子：
7.3
通讯作者：
Finch-Savage, W. E.
中科院分区：
文献类型：
--
作者：
Huang, Z.;Footitt, S.;Finch-Savage, W. E.
种子特征是植物适合度的关键组成部分，受母体环境温度的影响，并且温度会随着全球变暖而变化。为了研究这种温度变化的影响，使拟南芥植物沿着独特设计的聚乙烯通道沿着生长以产生种子，该通道具有反映局部全球变暖预测的热梯度。因此，植物经历了相同的温度和光照条件的变化，但不同的平均温度。一系列的种子相关的植物适合度估计进行了测量。在两种不同的生态类型中，温度对发芽行为有显著的非线性影响。母体温度低于15-16摄氏度导致显着更大的初级休眠。此外，生长介质中的硝酸盐对休眠的影响仅表现在低于15-16摄氏度的种子上。然而，对种子产量、数量或大小没有一致的影响。发芽行为的影响被证明是一个物种的特点，响应温度，而不是一年中的时间。在种子发育过程中，温度升高到这个临界值以上，有可能极大地改变随后种子萌发的时间和进入土壤种子库的比例。这对整个植物生命周期和物种适合度有潜在的影响，我们提供了直接测量全球变暖情景对母体环境的影响，对随后与物种适合度相关的种子特征的影响。为此，我们采用了独特的设备（热梯度隧道），允许在生长到种子收获期间对母体植物进行全球变暖的自然模拟。我们表现出显着的非线性种子成熟温度对休眠深度的影响，该特性决定了植物生命周期中从种子到幼苗的关键过渡的时间。这一点很重要，因为物候的变化会影响种群动态和植物多样性，但到目前为止，这一特征在全球变暖研究中被认为在很大程度上被忽视了。
Seed characteristics are key components of plant fitness that are influenced by temperature in their maternal environment, and temperature will change with global warming. To study the effect of such temperature changes, Arabidopsis thaliana plants were grown to produce seeds along a uniquely designed polyethylene tunnel having a thermal gradient reflecting local global warming predictions. Plants therefore experienced the same variations in temperature and light conditions but different mean temperatures. A range of seed-related plant fitness estimates were measured. There were dramatic non-linear temperature effects on the germination behaviour in two contrasting ecotypes. Maternal temperatures lower than 15-16 degrees C resulted in significantly greater primary dormancy. In addition, the impact of nitrate in the growing media on dormancy was shown only by seeds produced below 15-16 degrees C. However, there were no consistent effects on seed yield, number, or size. Effects on germination behaviour were shown to be a species characteristic responding to temperature and not time of year. Elevating temperature above this critical value during seed development has the potential to dramatically alter the timing of subsequent seed germination and the proportion entering the soil seed bank. This has potential consequences for the whole plant life cycle and species fitness.We provide direct measurements on the impact of global warming scenarios tothe maternal environment on subsequent seed characteristics related to species fitness. To do this, we employed unique equipment (thermal gradient tunnel) that allowed seminatural simulations of global warming to the mother plants during growth to seed harvest. We show dramatic non-linear seed maturation temperature effects on the depth of dormancy, the characteristic that determines the timing of the crucial transition from seed to seedling in the plant life cycle. This is important because shifts in phenology influence population dynamics and plant diversity, but until now, this trait has been considered as largely neglected in global warming studies.