Not so harmful after all! Garden weed common purslane is a ‘SUPERPLANT’ that holds the key to drought-resistant crops, scientists say
- Purslane is a common weed that many people struggle with in their gardens.
- The plant is able to withstand drought while remaining very productive
- In a new study, researchers have found that the plant integrates two distinct metabolic pathways to create a new type of photosynthesis
Purslane can be a nightmare for avid gardeners, but a new study may make you think twice about getting rid of the weed.
Purslane may be a “super plant” that holds the key to drought-resistant crops, Yale researchers say.
In their study, the researchers found that the plant integrates two distinct metabolic pathways to create a new type of photosynthesis.
This allows the weed to withstand drought, while still being very productive.
“This is a very rare combination of traits that has created a kind of ‘super plant’, which could potentially be useful in projects such as crop engineering,” said lead author Professor Erika Edwards. of the study.
Purslane can be a nightmare for avid gardeners, but a new study may make you think twice about getting rid of the weed
What is purslane?
Purslane, Portulaca oleracea, is an edible, leafy, frost-sensitive plant widely used as an herb and salad vegetable.
The reddish fleshy stems are densely covered with lobed leaves of green or golden color, depending on the variety, and reach 15 to 20 cm in height.
Purslane grows quickly from seed and the leaves are ready for picking in 6 to 8 weeks.
Photosynthesis is the process by which green plants use sunlight to synthesize nutrients from carbon dioxide and water.
Over time, different species have independently evolved a range of distinct mechanisms to enhance this process.
For example, corn and sugar cane have developed “C4 photosynthesis”, which allows them to remain productive at high temperatures.
During this time, cacti and agaves have developed “CAM photosynthesis”, which allows them to thrive in areas with little water.
Although C4 and CAM perform different functions, they both use the same biochemical pathway to act as “add-ons” to basic photosynthesis.
Previous studies have shown that purslane has both C4 and CAM adaptations, allowing the plant to be productive and tolerant during droughts.
However, until now, C4 and CAM were thought to function independently in leaves.
In their new study, the researchers showed that C4 and CAM activities are fully integrated in purslane.
In their study, the researchers found that the plant integrates two distinct metabolic pathways to create a new type of photosynthesis. This allows the weed to withstand drought, while still being very productive
The researchers studied gene expression in purslane leaves and found that both C4 and CAM function in the same cells, with the products of CAM reactions being processed directly in the C4 pathway.
The researchers hope the findings could help pave the way for drought-tolerant crops in the future.
‘In terms of engineering a CAM cycle in a C4 crop, such as maize, there is still a lot of work to do before this becomes a reality,’ Prof Edwards explained.
“But what we’ve shown is that both paths can be effectively integrated and share products.
“C4 and CAM are more compatible than we thought, leading us to suspect that there are many more C4+CAM species out there, waiting to be discovered.”
The study comes as the UK experiences the driest conditions since the 1976 drought.
Worryingly, the office met warned of ‘very little significant rain’ on the horizon – with conditions now so extreme that a garden hose ban affecting one million people in Hampshire and the Isle of Wight will come into effect at 5 p.m. today.
The Met Office says it is still too early to know how long the heatwave will last.
However, he reassures “there are indications of a return to more changeable conditions from around mid-August”.
HOW DOES PHOTOSYNTHESIS WORK?
Photosynthesis is a chemical process used by plants to convert light energy and carbon dioxide into glucose for plant growth, releasing oxygen in the process.
The leaves of green plants contain hundreds of pigment molecules (chlorophyll and others) that absorb light at specific wavelengths.
When light of the next wavelength strikes one of these molecules, the molecule enters an excited state – and the energy from this excited state is carried along a chain of pigment molecules until it that it reaches a specific type of chlorophyll in the photosynthetic reaction center.
Here, energy is used to drive the process of charge separation necessary for photosynthesis to take place.
The “hole” of electrons left in the chlorophyll molecule is used to “split” the water into oxygen.
The hydrogen ions formed during the water splitting process are ultimately used to convert carbon dioxide into glucose energy, which the plant uses to grow.