Sep 27, 2024 07:00:00

Algae that can photosynthesize in the dark have evolved on the bottom of the Arctic Ocean, and it is hoped that they will be used in agriculture.

For plants to grow abundantly, it is important that they receive sufficient sunlight and photosynthesize. However, a research team led by Clara Hoppe of the Alfred Wegener Institute has discovered plants that perform photosynthesis at the bottom of the Arctic Ocean, where almost no light reaches.

Photosynthetic light requirement near the theoretical minimum detected in Arctic microalgae | Nature Communications

https://www.nature.com/articles/s41467-024-51636-8

Plants can grow in near-darkness, new research shows – here are three promising benefits
https://theconversation.com/plants-can-grow-in-near-darkness-new-research-shows-here-are-three-promising-benefits-238469

Hoppe and his team lowered a light sensor to a depth of 50 meters in the Arctic Ocean and measured the light levels at the boundary where underwater plants no longer exist. As a result, they confirmed the presence of microalgae that thrive at light levels of just 0.04 μmol m ^-2 s ^-1 , which is 1/37,000 to 1/50,000 of the typical light conditions outdoors in sunny Europe. Previous

research has shown through computer simulations that 0.01 μmol m ^-2 s ^-1 is the limit light level at which plants can thrive, and this discovery has confirmed that photosynthesis under conditions close to the theoretical limit is actually occurring in nature.

According to Sven Patke, a biology lecturer at Edge Hill University, Hoppe and his colleagues' findings open up a number of possibilities for the field of plant science, including:

Increased crop yields
Cloudiness in the UK has been increasing in recent years, andit is known that by 2024, the hours of sunshine will be the worst since 1900. In addition, in countries and regions far from the equator, crops can be covered in snow during the winter, resulting in a lack of sunlight for them to grow.

However, by studying the microalgae discovered in this study, it is possible to develop crops that can be harvested even when there is little light, and it has been shown that by using biotechnology approaches, existing crops can be modified to produce greater yields even with short days.

Sustainable Agriculture
In recent years, indoor crop production using greenhouses and

vertical farming has become popular . However, these farming methods require artificial lighting to grow crops, which has been criticized as consuming large amounts of energy.

Therefore, if microalgae can be engineered to photosynthesize at lower light intensities without compromising crop yield, taste, or odor, this could reduce the energy demand for artificial lighting, reduce costs, and pass the savings on to consumers in the form of lower prices.Furthermore, advances in technology could potentially lead to reduced carbon dioxide emissions.

Realizing agriculture in space
One of the main challenges for future long-term missions to the Moon or Mars is 'how to obtain food.' Since the amount of light that reaches the Moon and Mars from the Sun is less than that on Earth, a highly efficient food production method that does not use much energy is required.

The discovery that 'photosynthesis is possible even in places where there is almost no light' suggests that crops may be able to be grown in places other than Earth, such as on spacecraft. According to Patke, combining this research with

crops that are suitable for growing in space , such as spinach, lettuce, and potatoes, could be an important first step for long-term missions in space.