Molecular genetic markers and their application in entomology.

The availability of molecular genetic markers have increased sharply following the advent of the polymerase chain reaction (PCR) and Southern Blot. Unlike morphological marker, cytological marker and isozyme marker, which revealed the differences at gene expressing level, molecular genetic markers offer several specific advantages over the expressing markers. Most importantly, they have good stablities, high variability and may mostly free from enviromental influences. In molecular genetic markers, multilocus marker and single\|locus marker are two types of vaulable technique widely used to survey genetic variation in diverse organisms including insects. Multilocus techniques such as RAPD, DNA fingerprinting, AFLP and RFLP detect genetic variations based on nucleotide differences, while single locus techniques such as SSR reveal variations through the polymorphism of alleles. The characteristics of some useful molecular genetic markers and their application and potential for answering questions about insects on phylogeny, taxonomy, ecology and biological control were reviewed.