HOPE FOR SEAWEED FARMERS: SEAFDEC’s Lab-Grown Seedlings Boost Farm Growth Multiple Times

Researchers at SEAFDEC/AQD have found and demonstrated a groundbreaking way to grow seaweed up to 6.5 times faster than traditional methods by using lab-grown, tissue-cultured seedlings.

Seaweeds like Kappaphycus alvarezii, known as the elkhorn moss or “guso,” are commercially important sources of carrageenan, an additive widely used in processed food products, pharmaceuticals, and cosmetics.

Apart from that, seaweeds are also nutritious, absorb carbon, and support the livelihoods of an estimated 200,000 fisherfolk households, in the Philippines alone.

However, seaweed farmers often struggle with poor-quality seedlings, leading to slow growth, low yields, and susceptibility to “ice-ice” disease which causes seaweeds to whiten and “melt.”

The Southeast Asian Fisheries Development Center, Aquaculture Department (SEAFDEC/AQD) is advocating for the industry to adopt tissue culture technology to produce seaweed seedlings that are disease-free and genetically robust, resulting in higher yields.

A team of SEAFDEC/AQD researchers, led by Joseph Faisan Jr., recently proved that their lab-grown tissue-cultured seedlings can significantly outperform the traditional “farm-sourced” cuttings that farmers derive from their previous crops.

Their findings were striking.

Compared to farm-sourced seedlings, tissue-cultured seedlings showed faster growth of between 1.5 and 6.5 times faster during three 60-day culture runs held back in 2021 during dry, dry-wet, and wet seasons.

They also found that tissue-cultured seaweeds had lower cases, or a delayed onset of “ice-ice” disease and harmful epiphytic filamentous algae, although these appeared only during fluctuating weather during the dry-wet and wet seasons.

In addition, they found that carrageenan extracted from both tissue-cultured and farm-sourced seedlings met or exceeded industry standards for yield and quality.

“Our results support the hypothesis that seaweeds are reinvigorated through tissue culture and the process could enhance their growth performance,” said Faisan.

More reasons to tissue-culture seaweeds

Faisan also highlighted the advantages of maintaining seaweed in laboratories or seedling banks, especially in typhoon-prone areas like in the Philippines.

“There were times when a typhoon washes out entire seaweed farms, and farmers could not immediately replant because they have no more seedlings to work with,” he said, adding that seedling banks can immediately supply to farmers in such cases so they can recover more quickly.

During seasons where seaweed health problems are a major issue, Faisan said that tissue culture should be able to provide farmers with disease-free seedlings that they can plant.

SEAFDEC/AQD Chief Dan Baliao also noted that more still needs to be done for tissue-cultured seaweeds to be the norm in fields.

“What we need to achieve now is the economies of scale in producing tissue-cultured seedlings so we can mass produce and provide the seedlings to farmers at an affordable cost,” Baliao said.

To learn more about the study of Faisan, along with his teammates Edcel Jed Samson, Hananiah Sollesta-Pitogo, Rheniel Dayrit, Vicente Balinas, and Dr. Leobert de la Peña, read their paper published in the Journal of Applied Phycology in 2024, “Seasonal growth, carrageenan properties, and resistance to disease and epiphytic pests between Kappaphycus alvarezii (Rhodophyta) var. tambalang (brown) tissue‑cultured and farm‑sourced seaweeds.” You may request for their article here: https://repository.seafdec.org.ph/handle/10862/6512