Profiling as method to identify relevant metabolites for phenological modelling purposes

经过几十年对木本植物休眠的积极研究，并将这一阶段划分为准休眠、内生休眠和生态休眠，这些阶段在物候模型中仍然没有得到充分的考虑。半机械模型仍然被用来描述植物的发育，其中的模型参数是根据物候观测进行优化的。虽然这可以找到一个适合数据的模型，但它在生理上的合理性并不能得到保证。在一个已完成的DFG项目中，我们能够证明甜樱桃的开花模型在较温暖的气候条件下失败了，这些模型没有经过生理上的可信测试。根据容易测定的参数(樱桃花蕾的鲜重、干物质、含水率)，结合经典的内气味测定方法，我们首次能够在大田条件下确定甜樱桃品种‘Summit’的隐形阶段--准、内-和生态气味。对这些阶段长度的了解为半机械模型的验证开辟了新的可能性，并使新的机械方法的发展成为可能。在这方面，最近研究了代谢物是否与木本植物的休眠阶段有关。对于甜樱桃，我们能够证明脱落酸和蔗糖的进程是决定内臭结束的合适的标志。然而，这些物质的浓度每年都有很大的变化。此外，物候学建模需要生理相关标记的多年数据来解释模型中环境的可变性。本项目的目的是系统地研究樱桃花蕾中不同类群(如碳水化合物、类胡萝卜素、氨基酸)的代表性，了解它们在休眠阶段的参与情况。应使用非靶向代谢物分析，以获得休眠期间哪些代谢物组的含量发生显著变化的概述。对于生理相关的代谢物，在不同时相的转变中表现出显著的变化，有必要证明是否与环境(气温、全球辐射等)有关。存在，这是物候建模的基本要求。对于那些显示出生理可信和环境控制的生物标志物，第二步必须进行有针对性的代谢物分析，以便在9年内确定芽中代谢物的含量。2012/13-2017/18年度的数据被用来生成一个机械性的三阶段模型，该模型按顺序考虑内生、生态和个体发育。在模型验证方面，2018/19-2020/21年度的数据将在柏林用于德累斯顿和盖森海姆站点的内部和多年数据，用于外部模型验证。此外，还将研究‘Regina’和‘Karina’品种建模方法的可转移性。

After decades of active research on dormancy of woody plants and the subdivision of this phase into para-, endo- and ecodormancy, these phases are still not adequately considered in phenological models. Semi-mechanistic models are still used to describe plant development in which the model parameters are optimised on phenological observations. Although this allows to find a model adapted to the data, its physiological plausibility is not guaranteed. In a completed DFG-project, we were able to show that models for the flowering of sweet cherries, which were not tested for physiological plausibility, failed under warmer climatic conditions. On the basis of easily determinable parameters (fresh, dry matter, water content of the cherry buds) and in combination with classical approaches for the determination of endodormancy, we were able to determine for the first time the invisible phases para-, endo- and ecodormancy for the sweet cherry cultivar 'Summit' under field conditions. The knowledge of the length of these phases opens new possibilities for the validation of semi-mechanistic models and enables the development of new mechanistic approaches. In this regard, it was recently examined whether metabolites are related to the dormancy phases of woody plants. For sweet cherries, we were able to show that the courses of abscisic acid and sucrose are suitable markers to determine the end of endodormancy. However, these substances had significant annual variations in their concentration. In addition, phenological modelling requires multi-year data of physiologically relevant markers to account for the variability of environment in the models. The aim of this project is to systematically investigate representatives of different groups (e.g. carbohydrates, carotenoids, amino acids) in cherry buds with regard to their involvement in the dormancy phases. Untargeted metabolite profiling should be used to get an overview of which groups of metabolites show significant changes in content during dormancy. For physiological relevant metabolites, which show significant changes in the transition of the different phases, it is necessary to proof whether a relation to the environment (air temperature, global radiation, etc.) exists, a basic requirement for phenological modelling. For those biomarkers that show a physiological plausibility and environmental control, in the second step a targeted metabolite profiling must be done, in order to determine the metabolite contents in buds over 9 years. Data for the years 2012/13-2017/18 are used to generate a mechanistic 3-phase model that considers endo-, ecodormancy and ontogenetic development in a sequential order. For model validation, data for the years 2018/19-2020/21 will be used at Berlin for internal and multi-year data at the sites Dresden and Geisenheim for external model validation. Additionally, the transferability of the modelling approach for the varieties 'Regina' and 'Karina' will be examined.