is a Gram-positive bacterium
which attacks only the Japanese beetle
). The bacteria
are used in some places in the U.S.
as biological control
s to kill the beetles, which were accidentally introduced to the U.S.
and which damage a large number of crop
and ornamental plant
When the beetle larvae are infected, they turn white because of all the bacterial spores (endospores) that develop in the insects' hemolymph (blood equivalent). Thus, the disease the bacteria cause is called "milky disease".
Bacillus popilliae bacteria are somewhat difficult to culture in the laboratory; they require a growth medium containing sugars (preferably glucose) yeast extract, casein hydrolysate, a delicate balance of amino acids, thiamine and barbituric acid.