The native coccinellid beetle Exochomus quadripustulatus is about 4-5 mm long and black with four red spots on their back, the front two of them being kidney shaped. The larvae are gray in color and sometimes have a whitish appearance due to wax filaments of their prey, the Pulvinaria scale. The eggs are laid in the egg masses of Pulvinaria scale or within colonies of wooly apple apple aphid. The eggs are elongate and have a yellow / orange color.
Mode of action:
The larvae as well as the adult ladybugs prey upon soft scales and woolly apple aphid. The adult ladybug lays her eggs in the egg mass of Pulvinaria. The hatching larvae eat the eggs of the Pulvinaria witin this egg mass, but also the bigger instars and scales who do not have produced an egg mass are being eaten. In the laboratory has been found that larvae or Exochomus quadripustulatus eat between 7899 and 9424 eggs of the horse chestnut scale. More prey are eaten at higher temperatures. Ten days after hatching the ladybirds eat at a temperature of 20°C /14°C (16 hours day / 8 hours night) per day about 120 nymphs of the horse chestnut scale. After 40 days this decreases to 3 to 6 nymphs.
Exochomus quadripustulatus is a biocontrol agent for several species of Pulvinaria (Pulvinaria spp.) that occur in nurseries on trees and shrubs or garden plants, such as hydrangea. It may also be used in urban parcs, road trees etc as well as in private gardens. The ladybug is also effective as biocontrol agent against woolly apple aphid (Eriosoma lanigerum) in fruit orchards. Also applicable on indoor plants against Pulvinaria scales.
effect of EXOCHOMUS
- Preys on all stages of Pulvinaria scales as well as woolly apple aphid
- empty, dead skin remains after action af ladybug
- effective at temperature above 15 ° C
- visible effect within 1 week
The product EXOCHOMUS
50 ladybug larvae in a paper bag on wood fibers.
minimum 2 days at 8-15°C.
may best be used at temperatures above 15 ° C. Below 15 ° C development is too slow and the effect will be minimal. Ladybugs do survive lower temperatures though.