Weidenbach Denise, Jansen Marcus, Bodewein Thomas, Nagel Kerstin A, Schaffrath Ulrich
a Department of Plant Physiology ; RWTH Aachen University ; Aachen , Germany.
Plant Signal Behav. 2015;10(4):1-3. doi: 10.1080/15592324.2014.1003752.
Aerial parts of plants are separated from the environment by a cuticle which functions in protection against desiccation and pathogen attack. Recently, we reported on a barley mutant with defect in the 3-KETOACYL-CoA-SYNTHASE (HvKCS6) gene, resulting in reduced coverage of the cuticle with epicuticular waxes. Spores of adapted and non-adapted powdery mildew fungi germinated less frequently on mutant leaves possibly because plant derived signals are missing. We used a shoot and root phenotyping facility to test whether depletion in epicuticular waxes negatively impacts plant performance under water-limiting conditions. While shoots of mutant plants grew slower at well-watered conditions than wild-type plants, they showed an equal or slightly better growth rate at water limitation. Also for roots, differences between mutant and parental line were less prominent at water-limiting as compared to well-watered conditions. Our results challenge the intuitive belief that reduced epicuticular wax might become a drawback at water limitation.
植物地上部分通过角质层与外界环境隔开，角质层具有防止脱水和抵御病原体侵袭的功能。最近，我们报道了一个大麦突变体，其3-酮脂酰辅酶A合成酶（HvKCS6）基因存在缺陷，导致角质层表面蜡质覆盖减少。适应性和非适应性白粉菌的孢子在突变体叶片上的萌发频率较低，这可能是因为缺少植物衍生信号。我们使用了一个地上部和根系表型分析设施，来测试角质层蜡质缺乏是否会在水分限制条件下对植物性能产生负面影响。虽然突变体植株的地上部在水分充足条件下比野生型植株生长得慢，但在水分限制条件下，它们的生长速率相同或略高。对于根系也是如此，与水分充足条件相比，在水分限制条件下突变体与亲本系之间的差异不那么明显。我们的结果挑战了一种直观的观点，即角质层蜡质减少在水分限制条件下可能会成为一个不利因素。
