Uwe Sonnewald is head of the division of biochemistry at the Friedrich-Alexander-University Erlangen-Nuremberg (FAU). He leads a research group trying to improve plant yield under optimal and stressful environmental conditions. Molecular genetics, genomics and biochemical methods are used to identify and characterize yield components, primarily for potato and cassava plants. Distribution of photoassimilates, mainly fixed during photosynthesis in source leaves, to harvestable plant organs, such as seeds, tubers or roots, is the most important determinant of crop yield. Allocation of photoassimilates is influenced by environmental and endogenous factors. In several crop plants temperature and day length significantly determine the switch between vegetative and generative growth. In this context the group used genetic and biotechnological approaches to overcome the heat-mediated of tuberization. Overexpression of the tuber-inducing FT homolog SP6A resulted in potato plants able to tuberize under elevated temperatures and achieving higher yields as compared to control plants. Beside this, many factors influencing source-to-sink relations have been deciphered and this knowledge has been used to design transgenic plants with improved biomass allocation. One example is the "push-pull" strategy which allowed the simultaneous stimulation of sucrose synthesis in leaves and the conversion of sucrose into starch in developing sink tubers. Source-to-sink interaction | Potato | Cassava

Wolfgang Zierer serves as the project manager for the Cassava Source-Sink project and leads the cassava research group at the division of biochemistry at the Friedrich Alexander University Erlangen-Nuremberg since 2018. Our group investigates cassava source-sink relations by analyzing existing cassava germplasm and by developing and analyzing transgenic cassava plants aimed at improved storage root yield. We are particularly interested in carbohydrate transport and metabolism, as well as cassava storage root development. In addition, we work on the development of better biotechnological tools for this important tropical shrub by expanding the cassava promoter toolbox and working towards improved cassava transformation. I hope that our work can make a meaningful contribution to the cassava research and breeding community and that we can help develop better cassava plants for smallholder farmers!

Christian Lamm is leading the CASS Transformation and Research Lab at the Division of Biochemistry in Erlangen, Germany. Apart from routinely generating genetically modified cassava plants of the model genotype 60444, Christian’s group investigates tissue culture methods enabling transformation of virus resistant, farmer-preferred cassava varieties. Techniques of interest include expression of morphogenic genes and chemical media additives, both of which are thought to be suitable to break recalcitrance and enhance the complex and lengthy transformation procedure. Further notable interests of Christian concern proteomics studies aimed at understanding the metabolism and physiology of Cassava.

Mercedes Thieme is the Scientific Data Manager in the group of Prof. Dr. Uwe Sonnewald and Dr. Zierer at the Chair of Biochemistry at Friedrich-Alexander University Erlangen-Nürnberg. As a data hub, she collects, curates, and integrates research data into the central project database in close collaboration with Prof. Dr. Lukas Müller. She is actively involved in improving data flows between consortium members and enhancing existing data management tools. Additionally, she plays a key role in data analysis and the statistical evaluation of research data within Dr. Zierer’s group.

Liu, Qing-Ting (刘庆庭) is postdoctoral researcher in the group of Wolfgang Zierer. He mainly focusses on metabolic pathways, starch synthesis and turnover. His current project is to synergistically increase the input of essential metabolites for starch synthesis of plastids, and induce a more active rate-limiting enzyme of starch synthesis, in order to increase the capacity of carbon assimilation and storage in cassava. In addition, he has interest to explore the communication and interplay between source and sink organ/tissues, to either fine-tune the current strategy or design new strategy to manipulate cassava sugar/starch metabolism, aiming to achieve yield improvement.

Maryam Nasr Esfahani is the postdoctoral researcher in the group of Prof. Dr. Uwe Sonnewald and Dr. Zierer at at the Chair of Biochemistry at Friedrich-Alexander University Erlangen-Nürnberg. Plants with lower gibberellic acid (GA) production typically exhibit shorter internodes and more compact growth. This can lead to improved allocation of photoassimilates and nutrients to sink organs. In the CASS project, she is interested in investigating whether reducing GA production in cassava plants through manipulating genes involved in GA biosynthesis can enhance photoassimilate production and increase the allocation of these photoassimilates to sink-organ biomass (tuberous roots of cassava). In addition, she is interested in exploring the responses of cassava plants to nutrient deficiency such as nitrogen and potassium.

Jolanda Kraner is Impact Manager for the CASS project at Friedrich-Alexander-University Erlangen-Nuremberg (FAU). She is responsible for science communication, stakeholder engagement, and impact reporting across the project’s international consortium. Her work focuses on making the outcomes of cassava research accessible and relevant for diverse audiences – from funding bodies and policy makers to farmers and the general public. With a background in business administration, marketing, and science communication, she supports the strategic development of the CASS project by translating scientific insights into real-world value. This includes designing public outreach initiatives, managing the project’s online presence, and facilitating collaboration between partners from Europe, Africa, Asia, and the Americas. Jolanda also leads the development of the project’s impact reporting framework, aiming to demonstrate how innovations in cassava research contribute to food security, climate resilience, and sustainable agriculture.

Srujan Kumar Talasila is a PhD researcher at Friedrich-Alexander-University Erlangen-Nuremberg (FAU) under the supervision of Dr. Wolfgang Zierer. His research focuses on understanding the formation and bulking of storage roots in cassava by studying the roles of genes, hormones, and metabolic regulation. By applying advanced methods such as spatial transcriptomics, he investigates how gene expression is organized within tissues, providing novel insights into the cellular and molecular processes that drive storage root development. Through his work, Srujan aims to contribute to a deeper understanding of cassava biology and to generate knowledge with potential applications for crop improvement and global food security.

Ana Marcela Florez Rueda is an evolutionary biologist with extensive experience in bioinformatics and plant developmental genetics. Originally from Colombia, Ana holds a Ph.D. from ETH Zurich, where she investigated molecular mechanisms underlying hybrid seed failure in tomato. Before joining the CASS project, Ana was a Humboldt Fellow at the Max Planck Institute of Molecular Plant Physiology in Potsdam, where she investigated the role of auxin in seed development in a large array of plant species. Her work bridges molecular biology, evolution, and bioinformatics to address complex questions in plant systems. She supports the CASS project by analyzing diverse bioinformatics datasets generated across the consortium.