Chilo tumidicostalis

MATERIALS AND METHODS
Laboratory study of the sugarcane moth borer, Chilo tumidicostalis (Hampson)
was conducted at National Biological Control Research Center (NBCRC), Central
Regional Center (CRC), Kasetsart University, Kamphaeng Saen Campus, Nakhon
Pathom, Thailand. The studies included mass rearing of sugarcane moth borer
C. tumidicostalis as stock culture, biological study of C. tumidicostalis and its natural
enemies.
Stock culture of Chilo tumidicostalis (Hampson)
The stock culture of the sugarcane moth borer, C. tumidicostalis were obtained
by collecting larvae of sugarcane moth borer from the sugarcane fields. They were
reared in the plastic boxes measuring 23 cm in diameter and 10.5 cm in height with
pieces of sugarcane stalk, until pupation. The pupae were kept in a petri-dish with
adequate moisture provided with water-soaked filter paper until the adult of
C. tumidicostalis emerged and then transfered them to the insect rearing cage
measuring 60x60x90 cm in dimension, with young shoots of sugarcane planted in a
clay pot.
A cotton soaked with honey 5% was provided as food for adult moths. After
oviposition occured on the leaf of the plant, the pot was taken out from the cage and
new pot of fresh sugarcane substituted. Four days after oviposition, eggs were
collected from the plant for hatching in the plastic boxes measuring 23 cm in diameter
and 10.5 cm in height with cut pieces of young shoot of sugarcane. The second instars
larvae were transferred to new plastic box with cut pieces of sugarcane stem as food.
It was changed every three day until pupation. Using this method, it was possible to
maintain a stock culture of sugarcane moth borer, C. tumidicostalis for study on the
biological attributes, construction of the life tables and other various experimental
purposes on a continuous basis. The stock culture of C. tumidicostalis were
maintained at the room temperature of 20-30°C (Figure 1)
Biological studies of Chilo tumidicostalis (Hampson)
The newly laid eggs of C. tumidicostalis was collected from the stock culture
and transferred into circular-shaped plastic boxes measuring 23 cm in diameter and
10.5 cm in height. The cover of plastic boxes were cut open with hole which was
covered with a organza screen for ventilation, some cut pieces of young shoot of
sugarcane were provided as food of larvae and adequate moisture provided with
water-soaked filter paper. The observation of the incubation period was done. The
newly hatched larvae were reared singly in plastic boxes, measuring 11x11x7 cm in
dimensions with cut piece of young shoot of sugarcane. The cut piece of sugarcane
was changed everyday until pupation. After pupation, pupae were kept singly in
plastic boxes, measuring 11x11x7 cm in dimension with young shoot of sugarcane
with adequate moist cotton. Daily observation was made and necessary data recorded
throughout the span of development period. The head-capsules of each stage was
preserved for necessary measurement to determine growth increment. The width of
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