Dr. and Associate Prof. Ri Tong Jo is Merited Scientist and a teacher of thremmatology in the agrobiology faculty of Pyongyang University of Agriculture. He is usually nicknamed “master of stevia.”
He has devoted nearly 40 years of his career to the research on breeding a new kind of high-yielding stevia suitable to the climatic and soil conditions in the country and the cultivation, seed-gathering and processing of the plant. Thus he has rendered a tangible service to solving the sugar problem.
He was born of a peasant in December 1938 when his country was under the Japanese imperialists’ military occupation. In the 1960s he learned biology at Kim Il Sung University and then finished the postgraduate course summa cum laude before starting his career as a teacher in the university.
Working as the dean of a faculty at Pyongyang University of Agriculture since 1982, he buckled down to the research into stevia which would be of great importance in solving the sugar problem in the country.
Harvested usually in August, it is a natural sweetening plant which belongs to a stevia kind of the aster family.
Stevia had long been under research in the country, but it failed to win the public favour owing to its aftertaste of bitterness and plant smell.
In the days of breeding a new variety, Ri, while giving lectures, pushed ahead with his breeding project in an experimental farm dozens of kilometres away from the university.
His nearly-20-year-long painstaking efforts bore fruit. He succeeded in cultivating a new kind of stevia which is better in leaf yields, content of sugar and sweet taste.
In the course of this, he presented scores of papers including those on studies of hereditary polymorphism of stevia and on the farming of a good kind of stevia. He also wrote a lot of books and reference books while training dozens of stevia scholars.
Later, he intensified the research on cultivation and processing techniques of stevia and promoted the work for introducing the plant across the country.
A scientist should set the problem the country wants to solve as his research project and carry it through to the end. And only when it produces good economic results can it be said to be a success. This is Ri’s belief.
This belief has served as the motive force for him to travel across the country to solve sci-tech problems arising in the cultivation, introduction and processing of stevia even when he is well over 80.
Today the stevia sugar powder and solution are in wide use in foodstuff, pharmaceutical, cosmetics and other industries.
More From Naenara (En)
The above-ground construction of the Tanchon port has been successfully completed in the DPRK. The respected Comrade Kim Jong Un
November 29, 2025
The above-ground construction of the Tanchon port has been successfully completed in the DPRK. The respected Comrade Kim Jong Un
A friendly match between the national women’s soccer teams of the DPRK and Russia took place at Kim Il Sung Stadium on November 27
November 29, 2025
A friendly match between the national women’s soccer teams of the DPRK and Russia took place at Kim Il Sung Stadium on November 27
Jonjin Senior Middle School, newly built as a comprehensive school in Rangnang District, Pyongyang Municipality, was inaugurated.
November 29, 2025
Jonjin Senior Middle School, newly built as a comprehensive school in Rangnang District, Pyongyang Municipality, was inaugurated.
The agricultural workers in Kumbu-ri of Sakju County and Tanghu-ri of Phihyon County in North Phyongan Province of the DPRK enjoy
November 29, 2025
The agricultural workers in Kumbu-ri of Sakju County and Tanghu-ri of Phihyon County in North Phyongan Province of the DPRK enjoy
The scientists of the Academy of Agricultural Science have newly established a regenerated rice cultivation technology. The new
November 28, 2025
The scientists of the Academy of Agricultural Science have newly established a regenerated rice cultivation technology. The new
Last month a light-industry goods exhibition “Development of Light Industry-2025” was held in Pyongyang. A wide list of goods
November 28, 2025
Last month a light-industry goods exhibition “Development of Light Industry-2025” was held in Pyongyang. A wide list of goods
Professor Pak Hyong Sop, PhD, is credited with teaching and studying the traditional Korean music. The candidate academician works
November 28, 2025
Professor Pak Hyong Sop, PhD, is credited with teaching and studying the traditional Korean music. The candidate academician works
Proud entities of rural rejuvenation have been spruced up one after another in North Hamgyong Province of the DPRK under the care
November 28, 2025
Proud entities of rural rejuvenation have been spruced up one after another in North Hamgyong Province of the DPRK under the care
The U-17 men’s ice hockey team of Primorsky Krai of Russia on a visit to Pyongyang at the invitation of the Ministry of Physical
November 28, 2025
The U-17 men’s ice hockey team of Primorsky Krai of Russia on a visit to Pyongyang at the invitation of the Ministry of Physical
The Pukchong County Fruit Processing Factory has been remodelled. The factory has been furnished with hundreds of pieces of
November 27, 2025
The Pukchong County Fruit Processing Factory has been remodelled. The factory has been furnished with hundreds of pieces of
Top ten IT products of the year have been nominated at the recent national IT achievements exhibition-2025. They are making a
November 27, 2025
Top ten IT products of the year have been nominated at the recent national IT achievements exhibition-2025. They are making a
New houses have been built at the Thaeyang Farm in Kyonghung County and at the Hyongje Farm in Puryong County, North Hamgyong
November 27, 2025
New houses have been built at the Thaeyang Farm in Kyonghung County and at the Hyongje Farm in Puryong County, North Hamgyong
The Hwangryongsan Green Technology Company has built a line of recycling waste concrete, which will be conducive to environmental
November 27, 2025
The Hwangryongsan Green Technology Company has built a line of recycling waste concrete, which will be conducive to environmental
Akhakgwebom is an old Korean encyclopaedia of music and dance.Compiled in 1493, it consists of nine volumes, divided into three ch
November 27, 2025
Akhakgwebom is an old Korean encyclopaedia of music and dance.Compiled in 1493, it consists of nine volumes, divided into three ch
The Mausoleum of King Tongmyong, the founder king of Koguryo (277 BC-AD 668) which was the first feudal state in the history of
November 27, 2025
The Mausoleum of King Tongmyong, the founder king of Koguryo (277 BC-AD 668) which was the first feudal state in the history of
Industrial establishments in the DPRK give priority to the readjustment and reinforcement of production lines and facilities to
November 26, 2025
Industrial establishments in the DPRK give priority to the readjustment and reinforcement of production lines and facilities to
This year many regions and farms across the country have made dynamic efforts to grow wheat as the early crop and dry-field rice
November 26, 2025
This year many regions and farms across the country have made dynamic efforts to grow wheat as the early crop and dry-field rice
New houses have been built at the Township Farm in Hochon County, South Hamgyong Province, and the Insan Farm in Rangnim County,
November 26, 2025
New houses have been built at the Township Farm in Hochon County, South Hamgyong Province, and the Insan Farm in Rangnim County,
The number of animals keeps growing in the Central Zoo in Pyongyang. So far this year, over 100 species of animals have bred. This
November 26, 2025
The number of animals keeps growing in the Central Zoo in Pyongyang. So far this year, over 100 species of animals have bred. This
, one of the three major waterfalls of Korea, is in Pagyon-ri in Kaesong. There is a singular pond, called Pagyon, originally a
November 26, 2025
, one of the three major waterfalls of Korea, is in Pagyon-ri in Kaesong. There is a singular pond, called Pagyon, originally a
More Articles