Back in 2016, during my early professional journey, I was fortunate to be selected for a seaweed cultivation project under CSMCRI, Bhavnagar, this opportunity has completely transformed the way I looked at the ocean. My field site was a small coastal village called Simar in Gujarat. Life there moved to the rhythm of the tides. Every day biomass monitoring, salty sea breezes, pollution-free village life, fishing boats, endless horizons where the sky met the Arabian Sea. Far from laboratories and conference rooms, my workplace was the coastline itself.
It was there that I worked closely with two remarkable seaweed species—Kappaphycus and Gracilaria—learning not only how to cultivate them, but also how deeply connected they are to the lives of coastal communities.
One of the greatest privileges of that journey was learning under the guidance of Dr. Vaibhav Mantri and his team at CSMCRI. Dr. Mantri is widely recognized as one of India’s leading experts in seaweed science, with contributions ranging from cultivation technologies to advanced research on seaweed-derived biocompounds. Beyond being an accomplished scientist, he is the kind of mentor who can make you see the extraordinary in what others might overlook. His passion for seaweed science is contagious. A simple conversation with him can transform a strand of seaweed from an ordinary marine plant into a story of biodiversity, innovation, livelihoods, and the future of sustainable development. Even today, every interaction with him leaves me learning something new and appreciating the ocean a little more.
Before diving into the science, it’s worth pausing to appreciate what seaweeds really are. To most people, they are just green, brown & red plants floating in the sea. Yet calling them “plants in the sea” barely scratches the surface. Seaweeds are living laboratories of nature, carrying unique compounds, genetic diversity, supports tremandous marine biodiversity and high ecological values that have fascinated scientists for decades. The more closely you observe them, the more fascinating they become. Over the past decade, seaweed cultivation has emerged as a promising component of India’s blue economy. Coastal states such as Gujarat and Tamil Nadu have seen growing adoption of seaweed farming, supported by research institutions, government initiatives, and private industries. Beyond its commercial value, seaweed cultivation creates sustainable livelihood opportunities for coastal communities, including women, youth, small entrepreneurs, and traditional fishing families. With relatively low investment requirements and minimal environmental impact, it provides an additional source of income while reducing pressure on declining marine resources. As the sector continues to grow, seaweed farming has the potential to strengthen rural coastal economies, enhance community resilience, and contribute to a more sustainable future.
India is blessed with one of the world’s longest coastlines, stretching over 11,000 kilometers and supporting an extraordinary diversity of seaweeds. Yet, despite decades of research and growing interest in seaweed cultivation, much of this marine wealth remains poorly understood at the genetic level. A recent study by Dr. Vaibhav Mantri and his team, revealed a striking gap in our knowledge: of the nearly 865 marine macroalgal species reported from Indian waters, only 207 have publicly available DNA sequence records. In simple terms, almost 90% of India’s known seaweed diversity still lacks genetic documentation, highlighting how much of our ocean’s biological wealth remains scientifically unexplored.
For many people, seaweeds are simply plants growing in the sea. In reality, they are among the most valuable biological resources on Earth. Seaweeds provide compounds used in pharmaceuticals, cosmetics, food products, agriculture, biotechnology, and numerous industrial applications. Important products such as agar, carrageenan, alginates, mannitol, and other bioactive compounds are derived from marine algae and play vital roles in everyday life. Beyond their commercial importance, seaweeds contribute significantly to marine biodiversity, carbon sequestration, and coastal ecosystem health. Can you imagine? Nearly half of the oxygen we depend on originates in the ocean. While microscopic phytoplankton do most of the heavy lifting, seaweeds also play a vital role in keeping marine ecosystems healthy and contributing to the planet’s oxygen & carbon cycle.
One of the biggest challenges in seaweed research is species identification. Unlike many terrestrial plants, seaweeds often exhibit remarkable plasticity in their appearance. The same species can look completely different depending on environmental conditions such as water temperature, salinity, light availability, wave action, and reproductive stage. Conversely, two entirely different species may appear almost identical to the naked eye. As a result, relying solely on morphology can lead to misidentifications that affect research, cultivation, conservation, and commercial applications.
To overcome this challenge, scientists increasingly rely on a technique known as DNA barcoding. Similar to scanning a product barcode in a supermarket, DNA barcoding uses specific genetic markers to identify species accurately. These genetic signatures provide a reliable method for distinguishing closely related organisms, discovering previously unrecognized species, understanding evolutionary relationships, and ensuring the authenticity of commercially important resources. In seaweed science, DNA barcoding has become an essential tool for modern taxonomy and biodiversity research. Many genera represented along India’s coastline have never been studied using DNA barcoding techniques, leaving substantial gaps in our understanding of marine biodiversity.
Interestingly, most genetic research has focused on commercially important seaweeds such as Kappaphycus, Gracilaria, Sargassum, Turbinaria, and Porphyra, which are valued for products like carrageenan, agar, alginates, pigments, and food ingredients. Meanwhile, many lesser-known species remain largely unexplored. This knowledge gap extends far beyond academic research. Accurate DNA-based identification is essential for successful cultivation program, new innovations, new drug discoveries, product authentication, biodiversity conservation, and monitoring invasive or harmful species. Misidentification can lead to economic losses and hinder our ability to unlock the full potential of these marine resources for future generations.
At a time when the global seaweed industry is expanding rapidly, India has a tremendous opportunity to strengthen its position. Developing a comprehensive DNA barcode database for Indian seaweeds would not only support scientific research but also enhance cultivation, conservation efforts, and the sustainable growth of the country’s blue economy.
As India continues investing in its blue economy and coastal development initiatives, understanding the genetic diversity of its seaweeds may prove just as important as cultivating them. The ocean has already revealed that it holds immense promise. The next challenge is ensuring that science catches up with the richness that nature has quietly nurtured along India’s shores for thousands of years.
