Some Jeju red-flesh citrus farms cut individual fertilizer components by over 70%; melon farms see 30–54% reduction

Bokbunja farms cut use by 82% in first year; ginseng plots yield 3.8 times more than conventional plots

Products commercialized after technology transfer; combined sales reach about 2 billion won since 2022

The microbial fertilizer product "Super Fertilizer" (left) and a cultivation manual for red-flesh citrus using microbial fertilizer. [Provided by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture and Forestry]
The microbial fertilizer product "Super Fertilizer" (left) and a cultivation manual for red-flesh citrus using microbial fertilizer. [Provided by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture and Forestry]

A technology that uses microorganisms to promote crop growth while significantly reducing chemical fertilizer use has been developed. At some Jeju farms growing red-flesh citrus, use of certain chemical fertilizer components fell more than 70 percent below recommended levels, while bokbunja — Korean black raspberry — farms in Gochang-gun cut use by about 82 percent in the first year of cultivation.

The Korea Institute of Planning and Evaluation for Technology in Food, Agriculture and Forestry announced Thursday that research supported by the Ministry of Agriculture, Food and Rural Affairs had produced a microbial fertilizer designed to promote crop growth, with field trials confirming its viability at citrus farms in Jeju and elsewhere.

The results came from a study on endospore-based microbial fertilizers for crop growth promotion, carried out from April 2022 to December 2024 by a research team led by professors Jeong Woo-jin and Kim Gil-yong of Chonnam National University, in collaboration with MC Biotech and the Gochang-gun Agricultural Technology Center, under the ministry's Technology Commercialization Support Project.

The research team developed the microbial fertilizer using endospore-forming microorganisms capable of surviving stably at high temperatures, including Bacillus subtilis PE7 and Bacillus velezensis CE100. The team also established a mass-production process for reliably producing microbial spores.

Unlike conventional microbial products that require dilution in water before use, the new approach allows farmers to cultivate 1 to 2 kilograms of powder themselves to produce about 1,000 liters of microbial fertilizer ready for application.

The research team conducted field trials across a range of crops, including Jeju red-flesh citrus, melon, ginseng and bokbunja. A review of chemical fertilizer use at Jeju citrus greenhouse farms from 2022 to 2024 found that nitrogen, phosphorus and potassium applications had broadly declined below levels recommended by the provincial agricultural research and extension service. At some farms, use of individual fertilizer components fell more than 70 percent below the recommended amounts.

At melon greenhouse farms in the Gochang-gun area, chemical fertilizer use dropped by about 30 to 54 percent. Bokbunja farms cut use by roughly 82 percent in the first year of cultivation. For ginseng, plots treated with the microbial fertilizer yielded 3.8 times more than those under conventional cultivation.

The research findings also led to technology transfer and commercialization. Chonnam National University transferred the crop growth-promotion technology — developed from the two microorganisms — to joint research partner MC Biotech, which built a production process and commercialized the microbial fertilizers under the names "Super Fertilizer" and "Super Bio." The products have recorded combined sales of about 2 billion won ($1.46 million) since 2022.

The research team also produced cultivation manuals to guide the use of microbial fertilizers for citrus and melon crops. In January and February 2025, the team shared its findings and application methods with about 1,500 farmers across seven organizations in Jeju, including agricultural research stations, agricultural technology centers and agricultural cooperatives.

Park Hong-jae, president of the institute, said the results were significant because they confirmed in real farming conditions that microorganisms can reduce reliance on chemical fertilizers, and because the work extended all the way from research to technology transfer, commercialization and distribution to farmers. "We will continue to support field-oriented agricultural and food R&D so that we can help reduce production costs for farmers and contribute to the spread of sustainable agriculture," he said.


adastra@heraldcorp.com