"The groundwork of all happiness is health." - Leigh Hunt

Insecticidal fungi find unexpected synergy in battle.

Biologists on the University of Maryland discovered a novel relationship between two species of fungi known for his or her ability to invade, parasitize and effectively kill insects. Instead of violently competing for the spoils of war, the 2 kooks cooperate peacefully and share their victims.

The findings, published within the journal Nov. 7, 2024, offer insight into a number of the biggest evolutionary achievements within the history of nature, based on study co-authors Raymond St. Leger, a distinguished university professor of entomology, and the Entomology P. There are HD. Candidate Huiyu Sheng.

“It's not survival of the fittest the way we often think. Sometimes, it's survival of the fittest,” explained St. Leger. “Instead of wiping each other out, these fungi appear to have evolved sophisticated ways to coexist — and we're only just beginning to understand that balance.”

The research focused on two species of the fungal genus Metarhizium, which is present in soils around the globe. Members of this fungal group protect plants from damaging abiotic stresses (equivalent to drought or poor nutrient availability) and harmful insects.

“These microorganisms have been named keystone species because they play an important role in both plant health and the control of natural insect populations,” St Leger said. “Our findings may help explain their extraordinary success in ecosystems around the world.”

Using sophisticated imaging techniques with fluorescent proteins that turned the fungi red or green, the scientists observed how the fungi interacted during colonization (infection, invasion and eventual killing) of insects. Instead of 1 strain dominating and leaving the opposite, the team found that the fungus neatly divided its territory — quite literally.

When colonizing insects, the 2 fungal strains exhibited an unusual ability to isolate their prey. One strain silently invaded the anterior segments of the insect host, while the opposite colonized the posterior segments, the 2 invasion zones being separated by a markedly sharp dividing line between them. This pattern held true whether the chosen prey was a big caterpillar weighing ten grams or a small fly weighing lower than one milligram.

St. Leger notes that “the sharpness of the description between the beginning of one fungus and the end of another seems rather strange.” “The boundaries separating classes from one another are inexplicably clear.”

So, why does this collaboration exist? The researchers imagine that every strain of fungus has adapted its unique characteristics and niches over time, allowing them to distribute limited resources.

“It's becoming clear that sometimes the key to evolutionary success isn't competing against your competitors — it's learning to share,” St. Leger said.

But how these fungi localize themselves inside their hosts and the way they dictate their regional distribution remain a mystery. The researchers hope to research the mechanisms chargeable for these host-sharing strategies and open recent avenues of research into how they will be used to reinforce each food security and terrestrial biodiversity. .

Understanding how different fungal species interact may help scientists and agronomists develop higher biological pest control methods and methods to advertise plant growth. Fungi already show incredible promise in protecting plants from mercury poisoning, enhancing crop growth and killing disease-causing insects, St. Leger noted.

“These fungi have shown that they are very adaptable,” he said. “They have been doing this for a very long time and have thus developed an arsenal of novel, sophisticated and subtle tricks. They are also very easy to genetically engineer so their applications are only limited by your imagination. are limited.”