Assessment of Three Common Methods for DNA Extraction in Trissolcus Sp. Egg Parasitoid Wasp of Green Stink Bugs

Extracting of genomic DNA with the proper quality and quantity is critical in the molecular identification of insects, whose morphological identification is problematic and affected by specific stage of life, size and sex. Also, storing insects under inappropriate conditions can have damaging effects on the quantity and quality of extracted DNA. Thus, choosing an appropriate protocol to provide pure DNA from these insects is essential.

In the present study to achieve an efficient method for DNA extraction from insect, we have applied and compared three common methods including (CTAB, Chelex and using commercial kit (animal tissue DNA isolation kit)). The quantity and quality of the extracted DNA were measured in two thermal conditions when DNA was stored at both -20 °C and -80 °C. The concentration of DNA extracted was measured on the Thermo Scientific NanoDrop 2000c.

The greatest and lowest average nucleic acid concentration of parasitoids were recorded for CTAB and Chelex. The mean DNA yield of parasitoids (Scelionidae) from different collection preservatives indicated that the greatest average DNA yield was recorded for 95% and 99.8% ethanol respectively, and 75% ethanol had the lowest value of average DNA yield.

CTAB method as a suitable method. and storing insects in -80°C at 99.8% ethanol as suitable methods with high performance to DNA extraction of parasitoids was suggested.