The Chinese Tomato With Popcorn Aroma.

Beijing; February 2026: In a research greenhouse in eastern China’s Zhejiang province, the tomatoes looked ordinary, but they carried a surprisingly sweet scent, the aroma of buttered popcorn.

It was not the result of accidental crossbreeding but a precise surgical edit in the tomato genome, performed by the CRISPR/Cas9 tool. Two genes responsible for suppressing aromatic compounds were simultaneously silenced. Then the tomatoes began to emit the signature scent of premium fragrant rice, akin to fresh buttered popcorn.

CRISPR/Cas9 Tool: The new gene editing tools, known as mitochondrial DNA base editors, can fix errors in the DNA inside a cell’s mitochondria. These mitochondrial DNA base editors could lead to gene therapies for serious conditions that currently lack curative therapies, according to the team led by researchers from East China Normal University and Lingang Laboratory. However, initially the researchers have reiterated that, efficient generation and correction of mutations in mitochondrial DNA (mtDNA) is challenging.

Mitochondrial DNA mutations have been associated with several genetic diseases in humans. These include Leber hereditary optic neuropathy, which causes vision loss; Leigh syndrome, a neurological disorder; and mitochondrial encephalomyopathy, which can cause stroke-like episodes and muscle weakness.

CRISPR-based therapies have become a viable option to treat diseases caused by mutations in the DNA inside a cell’s nucleus. However, the structure of the mitochondria makes it difficult to apply this technology to manipulate mitochondrial DNA. The main type of mutations that lead to mtDNA diseases are called specific point mutations. This refers to a change, deletion or addition of a single nucleotide base, or the blocks that make up DNA: adenine, thymine, cytosine and guanine.

Tomatoes are among the world’s highest-yielding vegetable crops. In 2023, China alone produced more than 70 million tons – more than a third of the global total. But behind this scale lies a flaw that consumers have long sensed: the flavour is fading.

Rather than attempting to restore the tomato’s traditional flavour profile, a team of Chinese and Australian researchers turned to fragrant rice for inspiration.

“People like fragrant rice, and its selling price is higher than that of ordinary rice”, stressed Xu Shengchun, deputy director of the Biotechnology Research Institute at Xianghu Laboratory. “Indian and Thai varieties have gained increasing popularity worldwide due to their distinct aromas. Their prices are often more than twice that of regular rice”.

In premium fragrant rice, the compound 2-acetyl-1-pyrroline (2-AP) produces a distinctive popcorn-like aroma. Its accumulation is negatively regulated by the BADH2 gene; when this gene is inactivated, 2-AP becomes enriched. Scientists have successfully replicated this mechanism in rice, corn and soybeans. But, until now, tomatoes have lacked any natural aromatic variety.

Xu and his collaborators identified two BADH2 homologues in the tomato genome: SlBADH1 and SlBADH2. Of these, SlBADH2 is continuously expressed throughout the plant’s growth cycle and serves as the primary aroma-suppression switch, while SlBADH1 plays an auxiliary role.

Using CRISPR/Cas9, the team created single, and double-mutant tomato strains. After confirming the absence of off-target effects, the plants entered the odour testing phase. Volunteers were invited to evaluate the fruit. Tomatoes with just SlBADH2 knocked out already exhibited a noticeable popcorn-like aroma in both fruit and leaves. In the double-mutant version, where both genes were silenced – the scent concentration grew four times.

The team also screened 706 samples of tomatoes with diverse genetic backgrounds. None were found to carry a natural loss-of-function mutation in SlBADH2. In other words, nature had never produced a tomato with a popcorn aroma. The laboratory did.

What pleased Xu even more was that the mutant tomatoes showed no significant differences from wild-type controls in key agronomic traits. Flowering time, plant height, fruit weight, soluble sugars and organic acids all remained unchanged. He had succeeded in enhancing flavour without compromising yield.
“Our ongoing work aims to introduce this fragrance to elite commercial cultivars”, Xu wrote in his research paper’s conclusion. “This may enhance their flavour complexity, potentially improving consumer preference and market value, much like fragrant rice varieties”.

Team Maverick.