The Agricultural Biology Department consists of three divisions. The Industrial Insect and sericulture Division is responsible for the development of the industrial use of insects, including conservation, feed, healing and the packaging of teaching and other materials. The Apiculture Division conducts research on bee breeding, beekeeping environment control, bee pollination, and development of functional materials for bee products. The Agricultural Microbiology Division is in charge of the national management of microbial resources, the development and commercialization of microorganisms that promote crop growth, also being responsible for the discovery of high value-added functional materials derived from microorganisms.
The Department made remarkable achievements in 2020. These include 73 articles published in world-renowned journals, 61 patents registrations, 65 patent applications filed, and 295 technologies transferred to the private sector. Among the outstanding achievements, one study was included in the 100 national R&D achievements
(1) Industrial Insect and Sericulture Division
1. Investigation and Conservation of Insects and Healing Program Using
Twenty insect species registered as national living resources have been preserved, and three species, Tenebrio molitor, Zophobas astratus, Locusta migratoria, were newly registered in 2020. Insect collections include over 180,000 specimens of 3,500 species, the DNA collection contains over 20,000 stocks of 4,800 species, and the CO1 DNA barcodes contains over 12,500 specimens of 3,500 species. Industrially useful insect species have been searched and selected, and breeding methods have been developed through physiological research. Mass rearing methods for Z. astratus and L. migratoria were developed, and artificial diets for Protaetia brevitarsis and T. molitor were also developed. For the development and dissemination of seed insect, excellent varieties of major industrial insects are being bred. In the case of T. molitor, the developmental and spawning characteristics of 17 populations were compared, and 103 strains with a short growth period and high weight were selected and maintained. Healing programs using insects have been developed with scientifically proven effects in order to diversify the uses of emotional insects. Species selection and evaluation methods were developed to utilize industrially insect resources, and four healing programs using insects such as Papilio xuthus and Teleogryllus emma were developed.
2. Utilization of the Black Soldier Fly for Environment Remediation and Development of High Value-added Substance
The production efficiency was improved through the research on improving the mating and oviposition efficiency in black soldier fly for the treatment of food waste, and the optimal decomposition method of food waste and agricultural byproducts was investigated. In addition, the standard for safe use of by-products was suggested through monitoring fecal soil. In order to improve the utility and value-added larvae of black soldier fly after food waste treatment, we investigated the immunity-inducing conditions for the mass expression of natural antibiotics from larvae, and evaluated the safety of high-functional feed additives. For the treatment of food waste, salinity reducing agents were selected and growth and toxicity evaluations were conducted in larvae.
3. Draft Genome of the Edible Oriental Insect Protaetia brevitarsis seulensis
The white-spotted flower chafer Protaetia brevitarsis seulensis is important insect species. In our previous work, Protaetia brevitarsis seulensis has been registered as a food material in Korean Food Standards Codex. Recently, we performed whole genome sequencing of Protaetia brevitarsis seulensis using Illumina and PacBio sequencing platforms. As a result, genome size of the insect was estimated to be 656.8 MB, with 40GB(155X) of short-read sequences. The 692.7MB of the representative draft genome was assembled into 224 contigs from 59.9GB(120X) of error-corrected long read sequences. The N50 of the assembled genome is 4.9 MB bases, and 344MB of the assembled contigs were covered by repeats, which are unclassified elements. Totally, 23,551 genes were predicted from the genome with an average size of 8217.3 bases, with the 99% completeness BUSCO score. Finally, 15,667 (66.52%) of genes are known to have homologous sequences in Genbank, and 10,844 (i.e., 46.04%) genes also have their gene ontology descriptions. The evolutionary relationship among these genomes was assessed with 218 single-copy genes through phylogenetic tree reconstruction. The genomes were grouped into exact family clans without any distortion. In continuation, the gain and loss among those genomes were also assessed for the insect genome.
Whole genome sequencing of Protaetia brevitarsis seulensis
4. The Prevention and Curing effects of Hongjam on Alzheimer’s Dementia and Parkinson Disease
Hongjam, which is prepared from mature silkworms containing various functional substances, shows an improvement effect on various memory in the mild cognitive impairment mouse model. In addition, it was confirmed that spatial memory, social memory, curiosity about new objects, and motor control ability were improved in the Alzheimer’s dementia mouse models supplemented with Hongjam and the accumulation of toxic β-amyloid plaque in the Alzheimer’s dementia mouse brains was diminished. Furthermore, in the Parkinson disease mouse model supplemented with Hongjam, the ability to hang on a wire and control limbs were superior to those of control Parkinson disease mouse model by improving motor performance. Hongjam also protected dopaminergic neurons in substantia nigra in the brains of Parkinson’s disease mouse model. Finally, we discovered that this memory improvement, the prevention and curing of Alzheimer’s dementia and Parkinson’s disease were accomplished by enhancing mitochondria function.
Accumulation of toxic β-amyloid plaque in the Alzheimer’s dementia mouse brains
5. Novel Application Development of Sericultural Products Including Silk Protein
Traditional sericultural products have been used as fiber. Functional sericultural laboratory studies the extraction and/or fraction method, the structural and conformation, physical and mechanical properties, and biological functionalities for widen the application fields of sericultural products including silk protein. Freeze-dried silkworm powder for blood glucose lowering effect, silk fibroin peptide for neroprotective and cognitive function, mulberry fruit, Nuedongchunghaco culture using Paecilomyces tenuips, silk eardrum patch have been investigated.
(2) Apiculture Division
1. Breeding of New Apis cerana and Apis mellifera
Korean Apis cerana population has greatly decreased in recent years by Sacbrood virus. The Sacbrood virus (SBV), a causative agent of larval death and colony collapse. therefore, development of methods to counter this viral disease is urgently needed. SBV disease, it is of paramount importance to have reliable methods that ensure for the propagation, breeding, and mating control of queens, such as artificial queen rearing and instrumental insemination techniques. Finally, we bred two line(Halla, Backdo) Apis cerana to against Sacbrood virus(2018). We evaluated honey collection, hibernation, and hygienic behavior of the triple crossed hybrid honeybees (Apis mellifera) which was selected among 8 cross combinations from 6 inbred lines in South Korea. The average honey collected by the triple cross hybrid (AC×D) was 10.7kg, which was higher than by other cross combinations, 6.1~9.1kg, or by commercial line, 5.3~6.5kg, as control group.
2. Integrated Pest and Disease Management in Honeybee Hives
Selection and development of substitute compounds for Fumagillin to control Nosema disease. Eight compounds were purified and isolated from the MeOH extract of Cordyceps militaris Media. Twelve compounds were isolated from the snowbell (Styrax japonica) honey. Finally, gallol and PC showed significantly higher activities than fumagillin and PG exhibited activity in similar level to fumagillin. That is, these three compounds (gallol, PC, PG) were selected as potential benefit alternatives for fumagillin. The Vespa vellutina, such as invasive pest, were found to have high control efficiency by traps on hills around beekeepers when controlling wasps in spring. The mixed with vinegar for sushi was the highest effective in capturing at 19%. In addition, dorsal black showed 100% insecticidal power after 240 minutes, 70 minutes, and 60 minutes, respectively, as a result of treating clothianidin (liquid hydrant, 8% active ingredient) with 80,000 ppm, 40,000 ppm, and 24,000 ppm to evaluate wasp pesticides, respectively.
3. Effect of Foraging Activity of Pollinators and Productivity Increase of Major Agricultural Crops
The rate of blueberry fruit setting when pollinated by Bombus terrestris was recorded at 87.7%, 89.6% under Apis mellifera, and 66.5% with Osmia cornifrons as pollinator. Compared to natural field conditions, the economic benefits to blueberry crop productivity of using B. terrestris as pollinators was higher by 9% and 15% when using A. mellifera. Under vinyl-house conditions, the fruit set rate of apricot was higher when pollinated by A. mellifera (92%) and B. terrestris (89%) compared to the control (83%). Consequently, the economic benefit to the apricot crop when A. mellifera was used as pollinator, compared with natural field conditions, was higher by 4% and 10% when B. terrestris was used. For welsh onion (Allium fistulosum) pollinated by B. terrestris, an economic benefit of 3.4% higher in the breeder's case was obtained.
4. Utilization of bee products on the quality and efficacy of bee products
Our projects have been characterised Korean honeys, bee pollens, royal jelly, propolis, bee venom, bee wax and drone pupae so that each product can be identified by the end user as authentic, recognised by unique compounds and known by its health benefits. Besides extensive chemistry expertise bee products has specific antimicrobial, anti-inflammatory, antioxidant expertise, and an array of other bioassays amongst its collaborators that can test bee products for their efficacy and provide clinical proof of the benefits of bee products. This will lead to greater access and competitiveness in the higher-value health food and nutraceutical markets. Also we carry out through linking, legal, media, social and scientific actions is aimed at creating a new regulatory and control frame that prevents the commercialization of false honey and bee products that is so damaging to people and the planet. The purpose of the study is to distribute and make available information on the manufacturing, processing and marketing of value added bee products.
(3) Agricultural Microbiology Division
1. Microbial resources management
Korean Agricultural Culture Collection (KACC) has been established in Rural Development Administration in 1995. KACC, which is organization based on the National law "The preservation, management and utilization for the agricultural genetic resources", conserves microbial diversity in an agricultural and food environments and provides various services to microbial research societies. KACC is domestic and international depository authority for patent organisms and also manage national integrated back-up depository for all patent microorganisms in Korea. KACC maintains over 25,900 cultures of microorganisms in 2021 and distributes around 4,000 cultures in a year for microbial researchers. It is accessible to the public via our website (http://genebank.rda.go.kr). KACC provides strain information from the website in which is not only simple information of microbes, but also morphological images and DNA sequence data. The database is constantly updated and reflects up-to-date information. KACC performs taxonomic and ecological researches on selected groups focused on food microorganisms including bacteria such as the genera Bacillus and lactic acid- and acetic acid- bacteria, and fungi including Penicillium and Aspergillus. KACC is going to provide long term preservation service for industry, university and public institute in 2021, considering the loss of microbial resources that is not registered as national resources.
2. Plant growth promotion microbe research
Our project is studying microorganisms that promote plant growth and health. Using microorganisms isolated from various environments such as soil, muscle, and root areas can help promote plant growth and immune activities to increase its resistance to environmental stress (temperature, drying, salt, etc.). To investigate the properties of beneficial microorganisms with these effects as mentioned above, mechanisms of action, and plant-microbial interactions, studies on active substances, including genetic analysis of microorganisms, are being conducted. We pick out microorganisms belonging to the genus Bacillus, Pseudomonas, Trichoderma and Variovorax, evaluate them at farms to commercialize, and actively participate in the development of them to microbial agents (ex; biostimulants and biofertilizers). In addition, through microbial cluster research, the composition and distribution of soil microorganisms are studied, and microbial clusters related to tomato growth is endeavoured to establish field application.
3. Biocontrol research
Eco-friendly biocontrol research is conducted to control plant pathogens and insect pests using microorganisms. Our project is aimed not only to control plant pathogens using the rhizosphere and endosphere microorganisms isolated from various environments but also to enhance plant immunity. Suppressing various fungal or bacterial plant diseases, microorganisms with antagonism against pathogens or microorganisms that induce resistance to plants are being studied. Moreover biocontrol research is being conducted using insect pathogenic bacteria (Bacillus, Serratia etc.) and insect pathogenic fungi (Isaria, Metarhizium, Beauveria, etc.) to control insect pests such as Beet armyworm, Bemisia tabaci and Thrip. In addition, research is performed on microbial-derived compounds that control pests, and some experts are actively participating in the development of biocontrol agents for the field application. Recently, research to control the occurrence of disease using microbiome is starting, and biocontrol research relied on bacteriophage or RNA interference (RNAi) will be promoted in the future.
4. Research on High-value-added microbial materials
The development of materials derived from natural products is demanded as consumers and industries avoid synthetic raw materials. Thus research on the development of high value-added functional materials is being carried out via the investigation of metabolites derived from microorganisms. And it is important to develop material using microorganisms to reduce by-products generated by chemical synthesis and environmental pollution. Research on the development of high value-added functional materials is being carried out through the discovery of metabolites derived from microorganisms. Research is underway to improve production by using biotechnology such as microbial genome editing and genome information to change characteristics into forms that can be used in agricultural and industrial sites or introduce biosynthesis pathways. To discover microbial-derived metabolites, we identify and characterize indigenous microorganisms isolated from domestic agricultural environments, wild flowers and food. In particular, we conduct the discovery of new or various surfactants through isolation yeast-derived materials, structure analysis and characterization. We also carry out the heterologous expression of biosynthesis genes to increase the yield of biosurfactant using genetic and metabolic engineering tools. In order to develop cell factories capable of producing carotenoids, a natural pigment material with antioxidant activity, with high efficiency, we are conducting research to discover microorganisms that produce various natural pigments in large quantities and to secure biosynthetic pathway genes. In addition, to use microorganisms as alternative protein foods in preparation for future food problems, research is being conducted to discover edible molds and bacteria, and to produce high-density proteins through production optimization and mass culture.