Bacillus thuringiensis (the “sotto” bacillus of silkworms)
Bacillus thuringiensis (bacilo «sotto» de los gusanos de seda)
- Date
- 1901 · confidence medium
- Place
- Tokyo, Japan
- Credited to
- Ishiwata Shigetane (1901); Ernst Berliner (1911)
- Field
- Life & health
⚠️ Disputed: the sources disagree.
What was discovered
In 1901 Ishiwata isolated the bacillus that causes “sotto” disease in silkworms; Berliner rediscovered it in 1911 in Thuringian flour moths and named it B. thuringiensis. Its protein crystals (Cry) kill insect larvae and underlie biocontrol and Bt crops.
Ishiwata's priority (1901) is accepted in Japanese and international literature, but the scientific name and first formal description are Berliner's (1915). The exact place of Ishiwata's isolation is not well documented.
What it led to
- first commercial bioinsecticides (Sporeine, France, 1938)
- identification of the Cry toxin and its genes (1980s)
- Bt transgenic maize and cotton crops