Institute of Ecology and Environmental Sciences of Paris (UMR 7618), UPEC, Créteil, France.
Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France.
Physiol Plant. 2020 Jan;168(1):227-236. doi: 10.1111/ppl.12971. Epub 2019 May 13.
Split-root system has been developed to better understand plant response to environmental factors, by exposing two separate parts of a single root system to heterogeneous situations. Surprisingly, there is no study attempting to maximize plant survival, growth and root system structure through a statistically sound comparison of different experimental protocols. Here, we aim at optimizing split-root systems on the model plant for Poaceae and cereals Brachypodium distachyon in terms of plant survival, number of roots and their equal distribution between the two compartments. We tested the effect of hydroponic or soil as growing media, with or without change of media at the transplantation step. The partial or total cutting of roots and/or shoots was also tested in different treatments as it could have an influence on plant access to energy and water and consequently on survival, growth and root development. Growing plants in soil before and after transplantation in split-root system was the best condition to get the highest survival rate, number of coleoptile node axile roots and growth. Cutting the whole root system was the best option to have a high root biomass and length at the end of the experiment. However, cutting shoots was detrimental for plant growth, especially in terms of root biomass production. In well-watered conditions, a plant submitted to a transfer in a split-root system is thus mainly lacking energy to produce new roots thanks to photosynthesis or adaptive autophagy, not water or nutrients.
分根系统已经被开发出来，以便更好地了解植物对环境因素的反应，通过将单个根系的两个独立部分暴露在异质环境中。令人惊讶的是，目前还没有研究试图通过对不同实验方案进行统计学上的比较，来最大限度地提高植物的存活率、生长和根系结构。在这里，我们旨在优化单子叶植物和禾本科模式植物拟南芥的分根系统，以提高植物存活率、根系数量及其在两个隔室之间的均匀分布。我们测试了水培或土壤作为生长介质的效果，以及在移栽步骤中是否更换介质。部分或全部切割根系和/或茎也在不同的处理中进行了测试，因为这可能会影响植物对能量和水的获取，从而影响其存活率、生长和根系发育。在移栽到分根系统之前和之后在土壤中种植植物是获得最高存活率、最多胚芽节轴根数量和最佳生长的最佳条件。然而，在实验结束时，完全切割根系是获得高根生物量和长度的最佳选择。然而，切割茎对植物生长不利，特别是在根生物量产生方面。在水分充足的条件下，由于光合作用或适应性自噬，而不是水或养分，处于分根系统转移状态的植物主要缺乏产生新根的能量。
