Science Journal

Two stories of the fruitful work of Czech scientists on the international scale in this month’s Science Journal, both touching on key modern issues of food production and climate change.

Photo: Palacký University in Olomouc

Firstly we speak with the Centre for Biotechnical and Agricultural Research at Palacký University in Olomouc, where a team of scientists has been granted a U.S. patent for their newly discovered compound. INCYDE is a derivative plant growth hormone that has proven able to increase crop yields and is currently being tested on various crops by a multinational agrochemical corporation. For the details of that we spoke to one of the authors of the research, Lukáš Spíchal.

“INCYDE, the name of the compound, is a shortening of “inhibitor of cytokine degradation”. Cytokinins are very important plant hormones that control a lot of important things during the development of a plant, including the development of the reproductive organs, so the level of cytokine is very important for these things. When we have a compound that is able to block enzymes that degrade such hormones, we can keep the level of cytokinins higher. This helps to increase the yield.”

At first sight it sounds relatively easy, but I suppose it is not. Why did it take this long to discover it?

Lukáš Spíchal, photo: Palacký University in Olomouc

“Actually the whole story started around 2004, when we studied the enzyme that regulates the cytokine level in plants and we were developing the inhibitor of this enzyme. One year later, in 2005, there was a publication by a Japanese group in Science showing that a mutation in the gene coding of this enzyme is very important for increasing the yield in one of the varieties of rice. So this was an important thing for us, that we saw that when this enzyme is not working in a plant then the reproductive organs are developing in such a way as to increase the yield. Of course there are a lot of things behind this, and not all of them are well understood right now. However, that was the main thing for us to follow on and we simply applied the compound to the model plant (Arabidopsis is used as a model plant in biology) and we saw that it really works. So in we got the same result through a chemical method as the Japanese group did through their genetic approach.

“So, yes, it seems to be quite easy once you know the mechanism.”

This worked for the model plant, is it something that can work for all kinds of crops or only for specific plants?

Arabidopsis, photo: Roepers, CC 3.0 license

“We started with Arabidopsis… which is very similar to Brassica, or rapeseed. So when we saw that it works with Arabidopsis we tried rapeseed and it worked very well, so that was very nice. Of course, as you mentioned, it would be good if it also works with other crop species. We also applied it to some cereals, to winter wheat and to spring barley and to maize. It worked, however we need to find an application window – when to apply and how much to apply in order to really see the effect. So not it seems we know how many times to apply, which is actually only once, and importantly when to apply - in which phenological phase of the development of the crop. And we know how much to increase the yield of barley. In the case of maize it works for increasing biomass, not grain yields.”

And this is an entirely natural process?

“Of course, we are using a chemical compound that is derived from the natural compound, so it is an artificial compound that we are putting on the plant, however the concentration of the compound we are using is very low, because it is highly targeted. So we are pushing the natural system to fine-tune the level of natural hormones – the natural compounds that are in the plant. “

---

Next up on our programme is trioxygen, better known as ozone, and particularly helpful in keeping life on earth from being incinerated by ultra-violet radiation. It has long been known that various chemical reactions in the atmosphere interrupt the creation of ozone and thus make a kind of “hole” in the layer that is damaging to the climate. Thanks to Czech researchers from the J. Heyrovsky Institute of Physical Chemistry, we now also know that this is happening at a faster rate than previously expected. The team’s article on the subject was recently one of the most widely read in the prestigious Journal of Chemical Physics, and one of its authors, Michal Fárník told us more about it.

“At the popular level, people think that Freons are responsible for ozone depletion, and that’s essentially true, but Freons are not very reactive – just the opposite, they are very stable, and they have a lifetime in the atmosphere of 50 to 100 years. In this time, they can wander all the way up to the stratosphere, and there a number of reactions can happen which, in the end, release a number of radical atoms – chlorine or bromine atoms – which then react with ozone in a cycle that destroys the ozone molecules, and the chorine atom remains available for another reaction and destroy further and further ozone molecules until it reacts with something else and disappears.

“Now, in this scheme involving many reactions that lead to chorine radicals, some of the reactions are not reactions in the gas phase – not between molecules in the gas in the stratosphere – but take place on the surface of ice particles in the so.-called Polar stratospheric clouds.”

Michal Fárník

And so those reactions on the surface of the ice particles are causing ozone depletion at a faster rate than previously thought?

“Actually this scheme was discovered in the 80s and a Nobel Prize was awarded for it, so that is not at all our discovery. What we did was investigate these small ice particles, which we call water clusters – just a couple hundred water molecules bound together – and we investigated how the other molecules can see them, how the other molecules interact witzh these particles, and what we found out was that the other molecules can be attracted to these particles from a much greater distance than was previously expected and used in models. So what we see in our experiment is that the ice particles are generated much faster than what was expected in models of ozone depletion.”