Plants Can Calculate How Many Flowers They Can Afford

Plants are not just passive green beings waiting for sunshine and rain. Beneath the surface of their leaves and flowers, they are making complex decisions and precise calculations. How many flowers can they afford to produce? How many seeds can they still generate before their nutrient reserves are depleted? A plant scientist Darya Volkava from CEITEC Masaryk University explores how plants keep their “internal accounts,” how roots and shoots communicate, and why a single genetic anomaly in a rapeseed field might help us understand the delicate balance between growth and reproduction. Her research opens the door to using plants’ natural strategies for more sustainable agriculture.

Darya, you claim that plants are good at math. What kind of calculations do they make, and what is at the end of this equation?

Plants constantly assess their environment and make decisions accordingly — it's a kind of internal math. They calculate how much energy they can invest into producing flowers and seeds based on the nutrients available, especially nitrates in the soil. Once they reach a threshold — the maximum number of seeds they can realistically support — they stop growing. It's a beautifully precise system of resource management.

You conduct your research on the laboratory plant Arabidopsis thaliana, a relative of rapeseed. How does this "plant math" manifest, for example, in rapeseed fields?

Rapeseed fields are a perfect natural display of this internal calculation. In spring, when you see those bright yellow fields stretching to the horizon, you'll notice that the plants are remarkably uniform in height and seed production. Each plant is adjusting its development based on the same environmental cues, particularly nutrient availability, and making the same internal decision about when to stop growing and how many seeds to produce.

As a scientist, what does it mean to you when you spot an anomaly in a uniform rapeseed field, such as an unusually tall plant?

This means I am looking at a mutant — a plant with a genetic alteration that causes it to grow differently from its neighbours. And that sparks my curiosity: could this mutant be calculating how to use available resources in a different way? Might it even have the potential to produce a higher yield?

Unfortunately, more often than not, such a plant simply fails to produce seeds. There is a strong connection between growth and reproduction: developing seeds drain resources from the mother-plant, eventually causing it to stop growing. There is even a simple experiment you can try yourself, either in your garden with peas or indoors with a kalanchoe. If you keep removing the flowers as they form, the plant will continue growing taller and for a longer time compared to those allowed to flower and set fruit.

How do plants internally coordinate all the complex processes like growth, flowering, and seed production?

At the tip of each shoot is the meristem, a small group of stem cells responsible for the plant’s vertical growth and flower formation. Think of it as the plant’s flower-producing factory. We study this structure using a special imaging tool in our research group at CEITEC. The activity of the meristem is heavily influenced by a plant hormone called cytokinin, which is produced in the roots and transported to the shoots. As long as the meristem receives enough cytokinin, it remains active, and the plant continues making flowers.

Once the seeds start developing, they require a lot of cytokinin to mature properly. They draw cytokinin away from the meristem. As more seeds develop, the meristem receives less cytokinin, eventually not enough to sustain its activity. At that point, the flower production stops. It’s a clever strategy to balance reproductive effort with available resources.

CEITEC / Říha Lab: Schematic representation of how soil nitrate availability regulates shoot reproductive development via cytokinin.

It sounds a bit like an internal competition for resources — seeds taking cytokinin for themselves. Is it a battle between different parts of the plant, or a sophisticated, controlled process?

It’s more like a sophisticated battle, which is at the same time a controlled process (laughs). Rapeseed needs to be extremely good in constantly making decisions. How much to grow, is it time to flower, and, most importantly, how many seeds to produce. They do such decisions based on the conditions they grow in, especially on the nutrients in soil. That is why fertilisers have been a central part of agriculture for so long. What’s fascinating is that, in this internal negotiation, the resources are ultimately channelled towards the seeds — the next generation — often at the expense of the mother plant herself. It’s a strategic sacrifice, where the plant prioritises successful reproduction over its own continued growth.

That’s right – your experiments showed that plants produce more flowers and seeds when given more nitrates. Do you already know how to "trick" plants into thinking they have more nutrients than they actually do?

Yes, that’s one of the exciting possibilities our research opens up. Nitrate boosts cytokinin production, which in turn stimulates more flower and seed production. If we understand this pathway well enough, we might be able to mimic the nutrient signals, making plants behave as if they were growing in richer soil even when they are not. This could lead to crops that grow better and produce more seeds with fewer chemical inputs, contributing to more sustainable agriculture.

At the beginning of this interview, we mentioned that each plant makes complex calculations. How difficult is it for scientists to decode these calculations, and what tools are you using?

It is quite challenging. To better understand these internal processes, we developed an advanced 3D live imaging technique that allows us to visualize and study the meristem and hormone dynamics in living plants in real time. This approach gives us crucial insights into how growth and reproduction are coordinated at the cellular level.

CEITEC / Říha Lab: 3D reconstitution of Arabidopsis inflorescence meristem with stem cells highlighted in magenta. Microscopy image acquired using Lightsheet Z1 system

Is this currently the central theme of your research?

More like a fascinating side-quest that came from my main topic. You see, for many years the major focus of our group was meiosis – a specialised type of cell division that occurs only in flowers and makes reproduction possible. Hence, the plants that fail to conduct meiosis properly often are sterile – we have a lot of mutants like this in the lab, and looking at them me and my supervisor got interested in the growth trade-offs we talked about earlier. I still have a project about meiosis regulation, but this one, I must say, is closer to my heart.  

What fascinates you most about this topic – both as a scientist and as a person?

As a scientist, I’m drawn to the complexity of the phenomenon. It’s deeply multi-layered, involving the integration of environmental cues, such as nutrient availability, with the plant’s internal decision-making processes. On a personal level, I’m fascinated by how plants, despite lacking a central nervous system, can coordinate their responses with such precision. Unlike animals, plants can’t simply move away when conditions become unfavourable. Instead, they must adapt to their environment and make the most of whatever nature provides.

As a woman in science – have you ever encountered obstacles or biases? Why did you decide to carry out this research specifically at CEITEC?

During my time at CEITEC, I never encountered bias or overwhelming obstacles. Everyone from my colleagues in the lab to the administrative staff was consistently supportive of me and my goals. I owe special thanks to my PhD supervisor, Karel Říha, who helped me realize my potential and provided everything I needed to excel in science.

In April, you were selected to present your research at the AFO festival in Olomouc in front of a jury composed of journalists and received feedback on how you communicate your research. Which piece of feedback gave you the biggest "aha moment"?

I guess, the importance of storytelling. As scientists, we are deeply fascinated by well-supported facts and the intricate details of the processes we study — details that, let’s be honest, can often seem dull to a general audience. Since the dawn of humanity, we’ve shared knowledge through stories. And today, as science becomes increasingly complex, I believe the ability to communicate research as a clear, engaging story is more important than ever.