Environmental pest plant ‘offers solution to search for natural rubber sources’
2 Mar 2025
Researchers in China said they have discovered a viable new source for one of industry’s most sought after natural commodities.
Scientists working at the University of Shihezi college of life science’s laboratory of agricultural biology assert that the prickly lettuce, Lactuca serriola, may be capable of being harnessed for natural rubber output.
While the product has been a mainstay of industry for 150 years, output has depended overwhelmingly on Congo and Amazon rubber plant species.
However, demand has grown in recent years, especially within the automotive and medical sectors, while US tariff laws aimed at China have increased pressure on other producers such as Thailand, Indonesia, Malysia, Cambodia, Sri Lanka and Vietnam.
Rubber plant farming, though, is rare north of the Tropic of Cancer, limiting the possibility of expansion in colder regions.
While several other plants have been identified as capable of producing the latex from which rubber is harvested, attempts to replicate the process at scale have been limited.
One of the most successful, guayale (Parthenium argentatum, pictured) is largely limited to the arid Chihuahua desert region spanning Mexico and the US, an area only slightly north of the rubber plant.
Its latitude span of between 25°N and 35° North only slightly exceeds that of the northernmost rubber plant distribution, the Tropic of Cancer (23.472°N).
But in their report published in the International Journal of Biological Macromolecules, the Shihezi researchers argued that the prickly lettuce, also known as the milk thistle compass plant, is capable of producing high-quality natural rubber (NR) at scale.
A key factor is the plant’s hardiness: Lactuca serriola’s upper geographical limit is commonly 60°N, well into north America, Europa and Asia.
Exceptionally, it can attain northernmost limits of 65°N and beyond and is sufficiently abundant to be classified as an invasive species.
Treating the plant with ethylene, methyl jasmonate (MeJA), and salicylic acid (SA) led to a significant increase in rubber content, reported the researchers.
Analysis of the mechanism by which plant hormones regulate rubber synthesis in Lactuca serriola demonstrate “significant potential as an alternative to the rubber tree for NR production,” the study concluded.
