1. Adaptation-in-action to herbicides.

An emerging picture from recent studies suggests that adaptation to stress combinations, acting either simultaneously or sequentially, might differ from the adaptation to individual stress factors. However, the exact ecological conditions that shaped the adaptation in the past are difficult to know. Consequently, understanding the mechanisms and consequences of plant adaptation to environment changes represents a big challenge. To address this, investigating the process of adaptation-in-action, during which the process of adaptation can be monitored and environmental conditions are manipulated, is the best (if not the only) approach. In this project, using the giant duckweed – one of the fastest growing angiosperm plants, as a model system, we aim to investigate the process, mechanisms and consequences of adaptation to individual natural stresses, herbicides and their combinations. More specifically, we aim to achieve three main objectives: 1) characterize multi-generational genotype-phenotype-fitness adaptation maps in response to both individual and combinations of herbicide exposure and natural stresses (salt, copper and species competition); 2) examine to what extent adaptation to natural stress facilitates or constrains adaptive responses to herbicides exposure; 3) identify the contribution of phenotypic plasticity to adaptive evolution to individual and combinations of stresses. This integrative study will bridge a knowledge gap in understanding the molecular mechanisms, processes and consequences of adaptation to stress combination, as well as reveal the yet unknown molecular and evolutionary mechanisms of herbicide resistance and thus facilitate new strategies to improve weed management.

Key collaborators:
Prof. Alex Widmer, ETH Zurich, Switzerland
PD.Dr. Klaus Appenroth, Friedrich-Schiller-Universität Jena, Germany
Prof. Rensen Zeng, Fujian Agriculture and Forestry University, China

2. Pleiotropy among signaling networks in tomato.

Most of the flowering plants have to attract pollinators, defend against herbivores and also recruit arbuscular mycorrhiza fungi (AMF). Recent studies revealed that the jasmonate (JA) signaling is involved in all three levels of plant-environment interactions, suggesting that the evolutionary trajectories of floral traits, plant defense and plant-AMF interactions are inter-connected and the selections imposed from pollinators can shape plant-herbivores and plant-AMF interactions. Yet, to what extend the signaling networks that are associated with plant-pollinators, plant-herbivores and plant-AMF are shared remains unknown.
In this project, we aim to characterize the gene co-expression network for the signaling networks that are involved in all three layers of plant-environment interactions in wild and domesticated tomato and systematically investigate the level of pleiotropy among different signaling networks. The results will not only reveal to what extent the natural variations of plant defense are shaped by other processes, such as plant-pollinator and plant-AMF interactions, due to pleiotropy, but also provide insights into the process of domestication in tomato.

Key collaborators:
Prof. Consuelo de Moraes, ETH Zurich, Switzerland
Dr. Thomas Städler, ETH Zurich, Switzerland
Prof. Yuanyuan Song, Fujian Agriculture and Forestry University, China

3. Plant evolution in a multitrophic community

Understanding the process of evolution in multitrophic communities represents a fundamental and outstanding challenge in evolutionary biology. In nature, plants are threatened by herbivores and colonized by diverse microorganisms. While accumulating evidence suggests that the plant microbiota changes the host’s defense against herbivores and is altered by herbivory, it remains unknown to what extent interactions between plant and its microbiota affect the process and trajectory of plant evolution under herbivore pressure. We investigate this topic using an experimental evolution approach using the giant duckweed, Spirodela polyrhiza as model organism.

Key collaborators:

Dr. Emmanuel Gaquerel, University of Strasbourg, France

Dr. Meret Huber, University of Münster, Germany

Prof. Dr. Heiko Hayen, University of Münster, Germany

Dr. Yubin Ma, Chinese Academy of Sciences, China

Prof. Sang-Gyu Kim, Korea Advanced Institute of Science and Technology, South Korea