Terrestrial Paleoclimate Research Group, Department of Geosciences, Baylor University, Waco, TX, USA.
Department of Geological Sciences, Texas Christian University, Fort Worth, TX, USA.
Am J Bot. 2020 Apr;107(4):676-688. doi: 10.1002/ajb2.1460. Epub 2020 Apr 9.
The size and shape (physiognomy) of woody, dicotyledonous angiosperm leaves are correlated with climate. These relationships are the basis for multiple paleoclimate proxies. Here we test whether Vitis exhibits phenotypic plasticity and whether physiognomy varies along the vine.
We used Digital Leaf Physiognomy (DiLP) to measure leaf characters of four Vitis species from the USDA Germplasm Repository (Geneva, New York) from the 2012-2013 and 2014-2015 leaf-growing seasons, which had different environmental conditions.
Leaf shape changed allometrically through developmental stages; early stages were more linear than later stages. There were significant differences in physiognomy in the same developmental stage between the growing seasons, and species had significant differences in mean physiognomy between growing seasons. Phenotypic plasticity was defined as changes between growing seasons after controlling for developmental stage or after averaging all developmental stages. Vitis amurensis and V. riparia had the greatest phenotypic plasticity. North American species exhibited significant differences in tooth area:blade area. Intermediate developmental stages were most likely to exhibit phenotypic plasticity, and only V. amurensis exhibited phenotypic plasticity in later developmental stages.
Leaves have variable phenotypic plasticity along the vine. Environmental signal was strongest in intermediate developmental stages. This is significant for leaf physiognomic-paleoclimate proxies because these leaves are likely the most common in leaf litter and reflect leaves primarily included in paleoclimate reconstructions. Early season and early developmental stages have the potential to be confounding factors but are unlikely to exert significant influence because of differential preservation potential.
木本、双子叶被子植物叶片的大小和形状（相貌）与气候相关。这些关系是多种古气候替代指标的基础。在这里，我们测试葡萄是否表现出表型可塑性，以及相貌是否沿藤条发生变化。
我们使用数字叶片相貌（DiLP）来测量来自美国农业部种质资源库（纽约日内瓦）的四个葡萄物种的叶片特征，这些物种在 2012-2013 年和 2014-2015 年的叶生长季节具有不同的环境条件。
叶片形状通过发育阶段发生了异速生长；早期阶段比后期阶段更线性。在同一发育阶段，两个生长季节之间的相貌存在显著差异，而物种之间在生长季节之间的平均相貌也存在显著差异。表型可塑性定义为在控制发育阶段或平均所有发育阶段后，在两个生长季节之间发生的变化。山葡萄和河岸葡萄的表型可塑性最大。北美物种的齿区：叶片面积存在显著差异。中间发育阶段最有可能表现出表型可塑性，只有山葡萄在后期发育阶段表现出表型可塑性。
叶片沿藤条具有可变的表型可塑性。环境信号在中间发育阶段最强。这对于叶片相貌-古气候替代指标很重要，因为这些叶片很可能是叶凋落物中最常见的，反映了主要包含在古气候重建中的叶片。早期季节和早期发育阶段有可能成为混杂因素，但由于差异保存潜力，不太可能产生显著影响。
