Morphological Differences and DNA Barcode Information on the Third Instars of Helicoverpa armigera and Heliothis maritima, Which Co-occur on the Soybean Fields in Miyagi Prefecture

Abstract

Helicoverpa armigera is a major food-crop and vegetable pest. Severe damage of soybean by the species has been observed in Miyagi Prefecture. It is difficult to distinguish the early-middle instar larvae of H. armigera from those of Heliothis martima, usually present on soybean; thus, an identification method for the larvae was developed using their morphology and standard DNA barcoding. Therefore, distinguishing their first and second instar larvae was morphologically challenging; however, their third instar larvae were distinguished using the base of D1 setae on the abdominal segments, especially in A1 and A8 of H. armigera, which is large and conically protruded. In contrast, the base of H. maritima is small and almost flat. Finally, their larvae were distinguished by standard DNA barcoding (a part of mt COI [cytochrome c oxidase I] region).