DNA Sequence Variation of the Tobacco Cutworm, Spodoptera litura (Lepidoptera: Noctuidae), Determined by Mitochondrial A+T-rich Region and Nuclear ITS2 Sequences.

In an effort to gain greater insight into the nature of the population genetic structure of the pest insect Spodoptera litura (Lepidoptera: Noctuidae), tobacco cutworms were collected from six Korean and five Chinese localities, and their mitochondrial A+T-rich region and nuclear internal transcribed spacer 2 (ITS2) were cloned and sequenced. The A+T-rich region and nuclear ITS2 provided a maximum sequence divergence of 2.88 and 1.82%, respectively. Overall, a low level of genetic fixation ( F = 0-0.02965 in the A+T-rich region and 0-0.34491 in ITS2) and no discernible isolated population were noted among most S. litura populations. Along with these results, the absence of genetic variance between Korea and China indicates a profound interrelation of the S. litura populations in the two countries, consistent with the current notion that S. litura has sufficient flight capacity for dispersal. [ABSTRACT FROM AUTHOR]