950. February 3 is "Soybean Day

February 3 marks "Soybean Day," a celebration deeply rooted in the Japanese tradition of “setsubun”, which is observed as the day before the arrival of spring. On this day, people scatter soybeans to ward off evil spirits while consuming an amount of soybeans equal to their age to symbolize a wish for robust health and good fortune.

Soybeans, an integral part of Japanese cuisine, manifest themselves in various forms such as tofu, miso, soy sauce, and natto. Beyond their local significance, soybeans are of global economic importance, serving not only as a staple in processed foods, but also as an important raw material for cooking oil and livestock feed due to their high protein content.

In commemoration of Soybean Day, today's feature highlights the importance of soybeans in Japan and around the world. The spotlight extends to ongoing soybean research at JIRCAS, offering insights into the crop's status and impact.
 

1. Global Soybean Status

According to the FAO's 2022 statistics, Brazil claimed the top spot in soybean production with a substantial 120.7 million tons. The United States followed close behind with 116.38 million tons. Notably, the United States had held the top spot until 2018, with a reversal occurring in 2019. In terms of export volumes, Brazil emerges as the dominant force, shipping an impressive 78.93 million tons. In 2022, Argentina, initially ranked fifth, jumped to third place in terms of soybean exports. Meanwhile, Uruguay maintained its sixth place ranking after being in the same position in 2021. Conversely, Paraguay, which was third, slipped to sixth.

Table 1．World Soybean Production in 2022
1　Brazil　　　120.70 MT（No.1 : 134.93 MT)
2　USA　　　  116.38 MT（No.2 : 120.71 MT）
3　Argentina　   43.86 MT（No.3 :  46.22 MT）
4　China　　      20.28 MT（No.4 : 16.40 MT）
5　India　　　    12.98 MT（No.5 : 12.61 MT）

Table 2．World Soybean Exports in 2022
1　Brazil　　     78.93 MT（No.1 : 86.11 MT）
2　USA　　　   57.33 MT（No.2 : 53.05 MT）
3　Argentina　　5.20 MT（No.5 :   4.28 MT）
4　Canada　　　4.28 MT（No.4 :  4.50 MT）
5　Uruguay　 　  3.06 MT（No.6 : 1.77 MT）

FAOSTAT (Data for 2021 in parenthesis, MT: million tons）

2. Soybean Status in Japan

According to the Ministry of Agriculture, Forestry and Fisheries (MAFF), the self-sufficiency rate for soybeans is estimated to be 6% in FY2022. Most of the imported soybeans (94%) are used for oil and feed, and the self-sufficiency rate for food, excluding oil and feed, is 23%. These facts indicate that both stable production of soybeans for oil and feed produced overseas and improvement of productivity and quality of domestically produced soybeans for food use are necessary.

3. JIRCAS Soybean Research Achievements

JIRCAS collaborates with domestic and international research institutions and actively conducts research and development initiatives. The primary focus of its efforts is to improve the uniform production and productivity of soybeans. In addition, JIRCAS is dedicated to the development of genetic resources and markers that will facilitate breeding and ultimately contribute to the improvement of soybean quality.

Research Achievement 1: Discovery of New Drought Stress Response Mechanism in Plants
― Overcoming "invisible drought" and paving the way for improvement in crop yields―

A team of researchers from JIRCAS, Kyoto University, Nagoya University, RIKEN, the University of Tokyo, and the National Agriculture and Food Research Organization (NARO) has discovered, for the first time in the world, that phosphate levels in plants decrease and trigger a phosphate starvation response at very early stages of drought, when leaf wilting is not observed. The results of this study have made it possible to quantitatively determine the extent of the plant response to "invisible drought" in the early stages of drought. This breakthrough paves the way for the development of innovative technologies to optimize water supply before crop yields are affected by drought. Consequently, the development of the experimental ridge drought system and the discovery of the phosphate starvation response as an indicator to capture "invisible drought" in this study are expected to contribute to improving food security in the future.

Nagatoshi, Y. et al. (2023) Phosphate starvation response precedes abscisic acid response under progressive mild drought in plants. Nature Communications
https://doi.org/10.1038/s41467-023-40773-1
https://www.jircas.go.jp/ja/release/2023/press202314

Research Achievement 2: A gene from wild soybean that increases protein content without reducing lipid content

Soybean seeds contain about 40% protein and 20% oil. Soybeans are also the most important source of protein and oil for human consumption. Over 71% of the world's vegetable protein and 29% of the world's oil comes from soybeans(link is external). However, soybean protein content is negatively correlated with oil content, making it difficult to develop varieties with high levels of both. Wild soybean, the ancestor of soybean, has a higher protein content in the seed than cultivated soybean. JIRCAS has successfully identified a gene from wild soybean that increases protein content without reducing lipid content (Pick Up 915).

Park, C.et al. (2023) A QTL allele from wild soybean enhances protein content without reducing oil content. Plant Genetic Resources- Characterization and Utilization. 
https://doi.org/10.1017/S1479262123000850
https://www.jircas.go.jp/ja/program/proc/blog/20231208

Research Achievement 3: Improvement of soybean functionality by developing soybean with high α-tocopherol content

Tocopherol is a fat-soluble antioxidant known as vitamin E. It has physiological functions in the prevention of lifestyle-related diseases such as cancer and atherosclerosis, as well as cardiovascular disease. Among the tocopherols, α-tocopherol has the highest vitamin E activity. However, the α-tocopherol content in soy is low, which limits the utilization of the functional properties of soy. JIRCAS has identified the DNA regions and candidate genes that regulate the tocopherol biosynthetic pathway in soybean (Pick Up 786). By modifying the tocopherol biosynthetic pathway, it may be possible to develop soybeans with higher α-tocopherol content.

Park, C., et al. Identification of quantitative trait loci and candidate genes controlling the tocopherol synthesis pathway in soybean (Glycine max). Plant Breeding (2023). https://doi.org/10.1111/pbr.13104
https://www.jircas.go.jp/ja/program/proc/blog/20230529

Research Achievement 4: Toward Soybean Rust Control in Asia

Soybean rust, which has become a major problem in South America, one of the world's major soybean producing regions, is becoming increasingly important in Asia, where it originated, as cultivation expands. In the 20 years since the outbreak in South America, fungicide efficacy has declined significantly due to heavy use, resulting in increased production costs and environmental impact. In Bangladesh, which is seeking to increase soybean production, a major shift in the pathogenicity of soybean rust has recently been observed (Pick Up 532). Under these circumstances, early prediction and diagnosis of soybean rust outbreaks, as well as comprehensive control of the disease through a combination of fungicides and host plant restrictions, mainly through the introduction of resistant varieties, may be effective in reducing the damage caused by soybean rust in Asia.

Hossain et al. (2024) Understanding Phakopsora pachyrhizi in soybean: comprehensive insights, threats, and interventions from the Asian perspective. Frontiers in Microbiology 14:1304205. 
https://www.frontiersin.org/articles/10.3389/fmicb.2023.1304205/full
https://www.jircas.go.jp/ja/program/proc/blog/20220510

Research Achievement 5: A Useful Tool for Developing Soybean Rust Resistant Varieties

JIRCAS has released soybean rust resistant varieties in Paraguay and Argentina in collaboration with local institutions (Pick Up 562). We are also collaborating to develop resistant varieties in Uruguay and Mexico (Uruguay; Mexico). In order to achieve strong resistance to many rusts, it is necessary to effectively and efficiently select individuals with multiple resistance genes in breeding varieties. We have identified markers for selecting for the presence or absence of seven known rust resistance genes. This information is expected to accelerate the development of rust-resistant varieties.

Yamanaka et al. (2023) Genetic mapping of seven kinds of locus for resistance to Asian soybean rust. Plants 12(12):2263. 
https://www.mdpi.com/2223-7747/12/12/2263
https://www.jircas.go.jp/ja/program/proc/blog/20220621

4. Soybean Varieties Developed by JIRCAS

「JFNC1」「JFNC2」
https://www.jircas.go.jp/ja/patent/plant/jfnc1_jfnc2
「Doncella INTA-JIRCAS」
https://www.jircas.go.jp/ja/patent/plant/doncella_inta-jircas
「蘇豆27（Sudou27）」
https://www.jircas.go.jp/ja/patent/plant/sudou

Reference
710. February 3 is "Soybean Day"
https://www.jircas.go.jp/en/program/proc/blog/20230203

Contributors:  KANAMORI Norihito (Information and Public Relations Office); NAKASHIMA Kazuo (Food Program); FUJITA Yasunari, NAGATOSHI Yukari, XU Donghe,  PARK Cheolwoo and YAMANAKA Naoki (Biological Resources and Post-harvest Division)