Food heritage: recovering Hong Kong’s rice varieties
In Hong Kong, one may taste flavours and cuisines from all around the world, because more than 90% of food is imported, even for staple food like rice. Local agriculture in Hong Kong appears to have been abandoned during the past several decades. About 70 years earlier, the area’s paddy fields had covered close to 9,466 hectares, with a yield of 20,000 tonnes of rice annually, according to the Chinese University of Hong Kong. Economic transformation and urbanisation of the New Territories have ushered in dramatic change, and all that remains are 12 paddy fields with a total area of 2.7 hectares. These fields can only yield nine tonnes of rice annually which barely satisfies 0.003% of the demand in Hong Kong, assuming the consumption of 3.3 kg of rice monthly per capita.
Lam has worked extensive on agricultural projects in South Africa, Northwestern China, and Southeast Asia, but he was conscious of the desire to give back to his own community. "I want to contribute to my hometown with my expertise so that people can know more about the forgotten history and culture on this land," he said.
His work also helps the people of Hong Kong reconnect with the food chain. “Nowadays, the distance between people and food seems so far; they buy food from supermarkets without knowing how hard the farmers have worked to produce them.”
With government support in the past two years, the centre has collected and recorded the genomes of 24 local agricultural products, including 13 varieties of rice, two peanut species, vegetables, and melons. The diversified species have shown that Hong Kong has the potential to modernise its agriculture and satisfy a lot more of its food demand given the right tools.
As a staple food, rice is of the main focus. The team took a close look at two varieties: Fa Yiu Tsai and See Mew. They examined seeds with bioinformatics analysis to make sure these two rice species were not “genetically polluted”, a term referring to hybridisation with foreign genes that have been inserted into the seed with human intervention. The team found that both varieties have preserved more than 98% genetic homogeneity which means that the genomic sequences of the two resemble their respective mother generation after rounds of propagation.
However, recovering the seeds proved to be no easy task. “Seed of Fa Yiu Tsai is extinct locally,” Lam said. “We had to ask for seeds from the US seed vault, so that trials in Hong Kong’s paddy fields can be done. It is quite sad indeed, because Fa Yiu Tsai has a special aroma that had made it one of the most favourite rice varieties produced and consumed locally before.”
This also highlights the importance of setting up local, smaller seed vaults. “Bigger seed vaults like the Svalbard Global Seed Vault in Svalbard archipelago have their limitations, as they might not be able to collect and save local species because of their comparative importance,” according to Lam.“ But like Fa Yiu Tsai, it represents something more. It is a collective attachment to a particular population, which has a rich history along with the development of the city.”
The team also compared the genomic data of the two rice varieties with the published genome resequencing data of more than 3,000 rice varieties. With the unique DNA markers of Fa Yiu Tsai and See Mew discovered, the team then can generate the “genetic ID card”, information that allows for authentication. In other words, farmers would be able to use such markers to verify the specific species of their products and prove that they have been locally farmed.
Lam projected a longer term vision: “From the genetics data, we hope to create something like a ‘brand’, something unique or marketing the quality products produced in Hong Kong, which can increase the revenue of farmers. We definitely cannot increase our production to compete with places like Thailand or Vietnam, but with the brand established, this might help attract more people to participate in the industry, hence reviving local agriculture.” While this vision is not yet within reach, the team is in the near future cultivating the varieties to best suit Hong Kong’s environment with climate change.
Read more about the project on the Hong Kong Seed Technology and Education Centre website.