Improvement of the identification technology for Asian Spongy
Moth(Lepidoptera: Erebidae) based on SS-COI
Abstract
Spongy moths, Lymantria dispar Linnaeus, are economically significant
quarantine pests. The Asian spongy moth (ASM), Lymantria dispar asiatica
and Lymantria dispar japonica, is more invasive compared with the
European spongy moth (ESM) because females are capable of flight and
larvae feeding on more host plants. Many countries have implemented
strict quarantine policies for areas where ASM is present to prevent its
introduction. ASM is distributed in most provinces of China, in view of
the high morphological similarity between Lymantria, especially larvae
and pupae, accurate identification is a necessary condition to prevent
ASM from invading new areas. Although the identification technology of
ASM has been developed previously, we have recently found that there are
potentially complex subspecies differentiation of spongy moth in China,
and there are new subspecies in South China and Yunnan (unpublished
data). The original identification method was more or less incomplete in
response to the newly discovered variation. Therefore, the purpose of
this study is to update the rapid detection technology of ASM: based on
the cytochrome oxidase I gene, a pair of ASM specific primers were
designed from samples obtained from known areas where spongy moth occurs
in China. These primers can effectively identify ASM of all life stages,
and can be used to identify ASM of all geographic populations in China.
It was confirmed that the primer provided accurate identification of ASM
in a wide range of annealing temperatures, indicating that it was
extremely stable. The sensitivity test explained that the lower limit of
detection was 30 pg/µl. In addition, the analysis of Lymantria samples
mixed with ASM captured in the field also showed the specificity of ASM.
Experimental methods allow accurate monitoring of ASM and reduce the
risk of ASM spreading to other regions.