Milky spore
Encyclopedia
Paenibacillus popilliae (formerly Bacillus popilliae) is a soil-dwelling, Gram-positive, rod-shaped
bacterium
. It is responsible for a disease (commonly called milky spore) of the white grubs of Japanese beetles.
The adult Japanese beetles pupa
te in the July time frame (in the North East US) and feed on flowers and leaves of shrubs and garden plants. During this adult stage the beetles also mate and the females lay eggs in the soil in late July–early August. The eggs hatch soon afterwards and in this larva
l or grub stage, they feed on the roots of grass and other plants. As the weather gets cooler and winter approaches the grubs go deeper in the soil and feeding declines as they over-winter.
In this August time frame when the grubs are close to the surface and actively feeding they are vulnerable to infestation by Milky Spore. This is also the optimal time frame for turf inoculation or applications with Milky Spore to increase Milky Spore in the soil environment (there are product specific guidelines that should be followed for Milky Spore application).
Resident spores in the soil
are swallowed by grubs during their normal pattern of feeding on roots. This ingestion of the spore by the host activates reproduction of the bacteria inside the grub. Within 7–21 days the grub will eventually die and as the grub decomposes, billions of new spores are released into the soil.
Milky Spore in the soil is not harmful to beneficial insects, birds, bees, pets or man; and Milky Spore like other bacteria is highly survivable in cold and drought conditions.
Bacillus
Bacillus is a genus of Gram-positive, rod-shaped bacteria and a member of the division Firmicutes. Bacillus species can be obligate aerobes or facultative anaerobes, and test positive for the enzyme catalase. Ubiquitous in nature, Bacillus includes both free-living and pathogenic species...
bacterium
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
. It is responsible for a disease (commonly called milky spore) of the white grubs of Japanese beetles.
The adult Japanese beetles pupa
Pupa
A pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...
te in the July time frame (in the North East US) and feed on flowers and leaves of shrubs and garden plants. During this adult stage the beetles also mate and the females lay eggs in the soil in late July–early August. The eggs hatch soon afterwards and in this larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
l or grub stage, they feed on the roots of grass and other plants. As the weather gets cooler and winter approaches the grubs go deeper in the soil and feeding declines as they over-winter.
In this August time frame when the grubs are close to the surface and actively feeding they are vulnerable to infestation by Milky Spore. This is also the optimal time frame for turf inoculation or applications with Milky Spore to increase Milky Spore in the soil environment (there are product specific guidelines that should be followed for Milky Spore application).
Resident spores in the soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
are swallowed by grubs during their normal pattern of feeding on roots. This ingestion of the spore by the host activates reproduction of the bacteria inside the grub. Within 7–21 days the grub will eventually die and as the grub decomposes, billions of new spores are released into the soil.
Milky Spore in the soil is not harmful to beneficial insects, birds, bees, pets or man; and Milky Spore like other bacteria is highly survivable in cold and drought conditions.
Sources
- http://www.milkyspore.com/milkyspore.htm
- http://ohioline.osu.edu/hyg-fact/2000/2001.html See Grub Control 1. Biological Control