Chilocorus nigrita (Fabricius)

Chilocorus nigrita is a general predator on all the diaspine scale insects. Pharoscymnus horni Weise could also be mass produced in a similar way. The predators could be easily multiplied on Hemiberlesia lataniae Signoret infested pumpkins. The beetles complete their development in 30 days time.

The predator can be multiplied on several diaspine scales (Aonidiella aurantii (Maskell), Hemiberlesia lataniae (Signoret and others). But it is easily multiplied on Melanaspis glomerata.

Chilocorus nigrita adults are released @100 per unit (cage or tray). Honey-agar is provided as supplementary food for adults.

Honey-agar is prepared by adding 1000 cc water, 10 gm agar agar powder, 200 gms sugar and 400 gms honey. The sugar is first added to 750 cc of water, once the sugar dissolves, add agar agar. The honey is mixed with 250 cc of water, when sugar agar solution starts boiling, honey solution is added and the mixture boiled for about half a minute. The hot adult diet is removed from the fire and small drops arranged on plastic plates or hard board or thick cards. On solidifying the diet is offered to the beetles.

The first beetles start emerging from the multiplication cage in about 30 days time and the beetles continue to emerge for about a week. The adults are collected daily and the days, collection kept in separate cages, 100 beetles each (A) where breeding of progenies has to continue, and 1000 beetles (B) each from where eggs are obtained for field release. The beetles start egg laying within 5 to 11 days. For field release (B) the eggs are obtained on cotton wool cut into squares, about 4 cm x 4 cm and laid over the feeding sites. The females readily oviposit on such pads.

Thirty five 4 cm x 4 cm pads of the cotton are placed in each egg obtaining adult beetle cage (B) containing 1000 adults each and the pads with eggs removed every day. Each pad contains about 40 eggs (usually more).