Trichogramma chilonis against cabbage moth

Madras (ViSCA) has identified T. chilonis as biological control agent against cabbage moth, Croccidolomia binotales Zeeler. It is an egg parasitoid that looks like a tiny wasp measuring 0.5-1.0 mm long. The total developmental stage from an egg to adult is just 7 days on the average. T. chilonis is totally dependent on its host for its food and nourishment. It can be mass produced in the laboratory using Corcyra cephalonica egg as host.

Mass rearing technique

• Prepare a sterilized culture medium containing rice hull, rice bran, and rice meal (1:2:1 ratio) using an empty half gallon ice cream.
• Infest the medium with newly laid eggs of C. cephalonica at biweekly interval.
• Collect the adults that emerge and allow them to oviposit on the oviposition frames.
• Collect the deposited eggs and introduce to the adult Trichogramma in test tubes for parasitization.
• Segregate the parasitized and unparasitized eggs after 3 days. Parasitized eggs turn black, while unparasitized ones remain white.

The collected parasitized eggs will be posted in tricho-cards for field release. The release is done by hanging the tricho-cards in sticks. These sticks will be placed in crucifer-growing areas infested with cabbage moth. This practice cannot totally control the infestation, but rather regulate the pest population below economic threshold level.

The technology ensures pesticide-free environment and provides natural control of cabbage moth. However, the production of T. chilonis is very tedious, hence, farmers may hesitate to adopt the practice.

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Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD)
©2006