Chinese scientists have developed a new tomato variety with "popcorn-like" aroma using gene editing technology, an advance aimed at tackling the problem of fading flavour in the fruit during transport and storage.
Tomatoes are one of the most widely cultivated and consumed grocery products globally, highly valued for their vibrant colour, culinary versatility, and nutritional benefits.
In particular, the fragrance of tomatoes significantly enhances the sensory appeal of food, influencing their consumption and market price.
However, tomatoes start losing their aroma due to metabolic changes which begin right after the fruit is removed from the vine, leading them to further lose their flavour during transportation and storage.
Now, scientists have generated the world’s first “extraordinary aromatic tomato plants” by simultaneously altering two key genes in tomato varieties using CRISPR/Cas9 gene editing technology.
Researchers disrupted a gene called betaine aldehyde dehydrogenase 2 (BADH2) in a variety of tomatoes. They found that blocking the gene led to an accumulation of 2-acetyl-1-pyrroline (2-AP), the organic compound responsible for the delightful "popcorn-like" aroma.
Scientists then screened tomatoes for forms of the BADH2 gene and found two variants, SlBADH1 and SlBADH2, and blocked their function. These mutant lines, they found, exhibited significantly greater 2‐AP content.
“The CRISPR/Cas9‐mediated genome editing technology was used to knock out individual or both SlBADH1 and SlBADH2 genes in the variety AC (Alisa Craig),” explained Shengchun Xu, an author of the study published in the Journal of Integrative Agriculture.
“These results indicated that although SlBADH2played a predominant role in regulating the 2‐AP accumulation in tomato, SlBADH1also significantly contributed to this regulatory process,” Dr Xu said.
The mutant lines did not differ significantly from the wild type in terms of any key traits, including flowering time, plant height, fruit weight, glucose, fructose, sucrose, organic acids like citric and malic acid, or vitamin C content, researchers found.
This indicated that the mutant varieties achieved the goal of “flavour improvement without yield loss”, scientists said.
“Ongoing work aims to introduce this fragrance to elite commercial cultivars, which may enhance their flavour complexity, potentially improving consumer preference and market value, like fragrant rice varieties,” said Peng Zheng, another author of the study.
