FIELD PRESERVATION OF COLEOPTERA FOR MOLECULAR-GENETIC ANALYSES

To establish an efficient method for preservation of field-collected b eetles for molecular genetic analyses, 5 different preservation treatm ents were compared: ethyl acetate, ethanol, Carnoy fixative, DNA isola tion buffer, and liquid nitrogen. Cryopreservation by immersion in liq uid nitrogen and subsequent storage at -80 degrees C was found to be t he best method for long-term storage. Storage in ethanol at room tempe rature preserved the DNA for approximate to 6 wk. Storage in DNA isola tion buffer was also effective but required the insects to be thorough ly homogenized to produce intact DNA, which destroyed insect morpholog y. Ethyl acetate and Carnoy fixative did not preserve the DNA. Preserv ation in ethanol was the easiest method, because it neither required g rinding of insects nor transportation and maintenance of special equip ment, such as a dewar flask for liquid nitrogen. However, because the DNA was found to degrade after approximate to 6 wk, ethanol was useful only for short-term storage.