By growing in a soil plants change the biotic and abiotic properties of the soil in which they grow.

Supervisor: P.J.J. Hooykaas Co-Supervisor: R. Offringa

We showed that constitutive and inducible chemical and morphological defenses against Western flower thrips differ between tomato and chrysanthemum plants.

Promotores: Prof.dr. T.H.W. Bäck, Prof.dr. M. Bongards (Cologne University)

In this project, we will study the genetic and environmental drivers of woodiness and stem lignification at the level of plant‐to‐gene‐to‐molecule.

Salicylic acid (SA) is a plant hormone, which is involved in the defense responses to pathogens and to abiotic stress, and in the regulation of plant growth and development.

Plastics have become an integral part of modern society due to their versatility and durability.

Promotor: C.A.M.J.J. van den Hondel, Co-promotor: Sandra de Weert

How can we make agricultural production systems more sustainable as the worldwide demand for healthy, safe food continues to grow? How can we develop healthy new food crops that have higher yields while requiring fewer harmful chemicals?

The AT-Hook Nuclear Localized 15 (AHL15) gene belongs to a plant-specific gene family of DNA-binding proteins. Overexpression of AHL15 in Arabidopsis thaliana delays developmental phase transitions whereas its loss of function causes a slight acceleration.

Promotor: Prof.dr. J. Memelink

Promotor: G.R. de Snoo, Co-promotor: H.H. de Iongh, C.J.M. Musters

Multicellular giant algae Chara species have been widely used in physiological studies for decades.

This thesis investigates the relations between metabolism and anatomy through the use of Magnetic Resonance Imaging (MRI).

In this thesis, I focused on studying the above- and belowground interactions of J. vulgaris from a plant-soil feedback (hereafter, PSF) perspective. I investigated the temporal variation of negative PSF and examined the effects of root-associated bacteria on plant performance and aboveground herbiv…

How were the Russians, under early modern conditions, able to incorporate this distant, undeveloped and, because frequent nomadic attacks, dangerous territory? And what role did the Kolyvan-Voskresensk plants play in this process?

Promotor: Prof.dr. E.F. Smets, Co-promotor: T.R. van Andel

Promotor: Prof.dr. P.G.L Klinkhamer

At almost midway through, the “Stoeplanten” (Pavement Plants) citizen science project has been very successful. This research was initiated by Nienke Beets, who while working for the Science Communication and Society research group and Hortus Botanicus, gave her contribution to the Stoeplanten proje…

Promotor: P.G.L. Klinkhamer, Co-Promotores: K. Vrieling, P.P.J. Mulder

PhD defence

The disappearance and reappearance of species of plants in the Netherlands is a normal phenomenon. In the period from 1981-2000 the number of plants to have disappeared was considerably lower than previously, whereas the number of species rediscovered is much higher. Climate change may be the cause.

Plants, are sessile organisms, have developed strategies to adapt to changes in their environment, in part by altering their growth and development.

The Plants & Planets exhibition brings two worlds together in a dazzling mix of science, nature and art. It opens at Old Observatory Leiden and Hortus botanicus on 7 February.

Restoring a natural plant environment on exhausted agricultural lands and in nature areas is difficult. We can speed this up by steering the soils towards the desired situation. This is what Martijn Bezemer, newly appointed Professor of Ecology of Plant-Microbe-Insect interactions at Leiden University’s…

Amorphophallus decus-silvae, or the ‘penis plant’ as it is known, has just flowered at the Hortus botanicus. It flowered for two days, and then the pollen, which the male flowers produced was collected. As far as the plant experts at the Hortus can tell, this was just the third time that this species…

Harvesting rice from the same field, without planting new rice plants? A discovery may bring this scenario closer. Leiden scientists have discovered a gene that allows annual plants to grow after flowering, instead of dying. Publication on 13 April in Nature Plants.

Producing offspring of a crop without sowing and that is even bigger than the parent plant. According to Leiden researchers this can be achieved by overstimulating a single gene that rejuvenates cells, including bringing them back to the embryonic phase.

All kinds of reasons have been put forward for why plants apparently fail to make maximum use of the available light. None of these reasons can explain why after two billion years of evolution they are not black, like industrial photovoltaic solar cells. Are we missing something?

Work officially started on Schilperoortpark at the Leiden Bio Science Park on Wednesday 6 March. Town councillor Paul Dirkse and Vice-Chancellor of the Executive Board of the University Martijn Ridderbos planted the first tree together with Cas Schilperoort, grandson of Professor Rob Schilperoort, the…

Plants can’t run away from enemies. Still, it would like to keep life-threatening herbivores at a distance. This can be done with odours. Klaas Vrieling of the Institute of Biology Leiden found out with his team how plants change odour production to keep the munchers at a distance.

Plant biologist Pingtao Ding, assistant professor at the Institute of Biology Leiden (IBL), has received a 2.4 million European grant from the European Research Council (ERC). This ERC Starting Grant for promising young researchers allows him to unravel the molecular mechanisms by which plants resist…

Promotor: Prof.dr. L.J. Slikkerveer

Just like us, plants also produce growth hormones, and they also go through an ageing process. The study of the genes and mechanisms behind these processes is useful not only for crop breeding and agriculture, but also for medical research. That is the view held by Professor of Plant Developmental Genetics…

The Netherlands is losing plant species that rely on pollination by insects. Leiden environmental scientist Kaixuan Pan demonstrates this after analysing 87 years of measurements from over 365,000 plots. The news is alarming for our biodiversity and food security. ‘75 per cent of our crops and 90% of…

Plants love favourable microbes such as bacteria and fungi: they grow better and become healthier. Jos Raaijmakers, Professor of Microbial Ecology, is in search of the right microbes to be used in agriculture. Inaugural lecture 13 November.

For nine years he worked on the three-volume standard work Plant Galls of Europe. It yielded 2300 pages about 10,000 species of European galls, abnormal outgrowths in plants caused by parasites. Hans Roskam from the Institute of Biology Leiden: ‘The abundance of galls says something about the natural…

A plant that takes metal from the ground all by itself: a natural way to mine or to clean the soil. PhD student Roderick Bouman (Hortus Botanicus Leiden) described a new plant species from Sabah, Borneo, which can be used to extract nickel. In an open access article in Botanical studies, he and the…

Just like every other organism on Earth, plants’ ultimate goal is to survive and reproduce. In order to achieve this, they must make trade-offs between where and how to allocate their finite set of resources. Whether they put their resources and energy into their growth, reproduction or maintenance,…

Fluctuations in individual plant communities contribute to the stability of an ecosystem as a whole, a study published in Ecology Letters shows. Nadia Soudzilovskaia and colleagues for the first time used data from plant communities across five continents to prove this hypothesis.

Emeritus Professor Ben Lugtenberg edited a book on “Principles of Plant-Microbe Interactions” together with Paul Hooykaas, Eddy van der Meijden and Jos Raaijmakers, all from the IBL.

Research on Asian plants is his life's work. Now a crown is added to that: a plant from the coffee family bearing his name. Paul Kessler is LUF professor of botanical gardens and botany of South East Asia and Scientific Director of the Hortus botanicus. 'Completely unexpectedly, you get to see the results…

Plants are able to resist a pathogen’s attack by a dual innate immune system. The relationship between the two pathways was not clear, but it turns out that they mutually potentiate each other, as assistant professor Pingtao Ding (Institute of Biology Leiden) and colleagues (The Sainsbury Laboratory,…

Environmental scientists in Leiden have found that the so-called leaf economics spectrum for plants can not only be applied to terrestrial ecosystems, such as forests and grasslands, but also to wetlands. Furthermore, they showed that wetland plants generally have a fast-return strategy, meaning they…

Drained leaves and plants stripped bare. Insects can completely destroy crops. Soon, these situations may be behind us, with the new pesticide developed by Leiden and Wageningen researchers. With their plant-based ‘insect glue’, insects are incapacitated.

The MicroSOS project is designed to bring together academic and industrial partners with different expertises to address challenges that agriculture is facing due to climate change and invests in the development of microbiome-based solutions towards more sustainable agricultural practices.

Leiden physicists are helping Wageningen plant researchers to study unpredictable plant embryos. For this, they are using a novel two-photon fluorescence microscope, aided by a 30 thousand euro ZonMW grant.

There is much wrong with the taxonomy of the plant genus Phyllanthus. Roderick Bouman of the Hortus botanicus Leiden has developed a new phylogeny for Phyllanthus and exposes the evolution of the plant genus. Publication in TAXON.