Human population in the world is growing. And we will need to feed all these people. How can we do that without limited resources and farming capabilities, not putting even more damage on the wildlife. Scientists at the University of Melbourne have put their ears on the clock the plants use to know when to start and stop growing.
Plants adjust their metabolism to save energy during the hours of darkness. Image credit: Fischer.H via Wikimedia (CC BY-SA 4.0)
Plants know what time it is. They grow during the optimal hours of the day, they rest at night. And it is not just light-sensing capabilities – they actually regulate their metabolism by the means of some biological timekeeping. If we understood how this mechanism works, we could use it for our own advantage, improving yields and harvesting more food every year.
Scientists from Melbourne explain that while plants do not sleep, they still adjust their metabolism during the night to conserve energy. This helps the plants concentrate their energy on growing the next day, employing photosynthesis. This is actually quite interesting. If you didn’t eat enough during the day and got hungry at night, you could run up to the fridge at midnight with no problem. Meanwhile, plants need to predict the length of the night to have enough energy to avoid damage till sunlight is available again for photosynthesis. That is why plants need to have a very precise clock to retain a positively accurate day rhythm.
Scientists conducted a study into the way plants regulate their metabolism according to the time of day. They found that the accumulation of sugars produced from photosynthesis allows the plant to regulate its metabolism precisely to the next day. In other words, sugar accumulation from photosynthesis allows plants to adjust the pace of their circadian clock.
Dr Mike Haydon, lead researcher of the study, explained: “We have now found that a different metabolic signal, called superoxide, acts at dusk and changes the activity of circadian clock genes in the evening. We also found that this signal affects plant growth. We think this signal could be providing information to the plant about metabolic activity as the sun sets”. But how will this knowledge help us grow more food?
Well, understanding this mechanism will help us to learn to grow plants in different environments. Especially artificial ones, like vertical gardens that are becoming more and more popular in urban settings. Eventually scientists will be able to fine-tune circadian rhythms of plants, which should significantly increase harvests and make our crops more resistant to extreme weather events which are going to become more frequent in the future due to the climate change.
Source: University of Melbourne