1. Introduction
Conogethes
punctiferalis (Guenée), is an important agricultural pest of
chestnut (Castanea
mollissima ), peach (Amygdalus persica ), apple (Malus
pumila ), maize (Zea mays ), and sunflower (Helianthus
annuus ) (Luo and Honda, 2015). In some regions of China, it has become
the main pest of corn, causing more significant damage thanOstrinia furnacalis (Guenée), the most prevalent corn pest in
China (Wang et al., 2006). C. pinicolalis (Lepidoptera:
Crambidae) is a sibling species of C. punctiferalis , even though
it is considered the same species at the early stage. Koizumi first
identified and classified the C. pinicolalis as another type ofC. punctiferalis and identified and classified the C.
pinicolalis as another type of C. punctiferalis commonly known
Pinaceae-feeding type in 1963 (Koizumi, 1963). Honda and Mitsuhashi
identified and distinguished the difference between them in the adults,
larvae and pupal stages (Honda and Mitsuhashi, 1989); Konno et al.
tested and reported that they were different species from their response
to different spectra of host-plant constituents (Konno et al., 1981); In
the end, the pinaceae-feeding type was named C. pinicolalis in
2006 (Inoue et al., 1982).
The two sibling species,C.
punctiferalis and C.pinicolalis,are important pest species in China. These two insects are similar in
morphologically, almost indistinguishable at the egg, larval and pupal
stages, and only well-trained entomologists can identify them by some
morphological characteristics in the adult stage. Moreover, they are so
similar that they both use (E)-10-hexadecenal (E10-16:Ald) and
(Z)-10-hexadecenal (Z10-16:Ald) as their main sex pheromone components,
but their foraging ranges are widely differentiated. C.
punctiferalis is a polyphagous species posing a major threat to over
100 essential plant species (Lu et al., 2010), while C.
pinicolalis is an
oligophagous
insect, mainly fed on few pine trees, especially for Pinus
massoniana (Masson pine). Their feeding preferences may be associated
with olfactory and gustatory system or digestive system, and this
preference ultimately must manifest as the result of the regulation of
proteins, genes, and their pathways. Therefore, it was of great interest
to unveil the difference in some function genes or proteins between the
two species.
In this study, we applied a proteomic technique, the isobaric tags for
relative and absolute quantification
(iTRAQ),
and RNA sequencing-based transcriptome technique. The transcripts with
new exons were identified from an alternative splicing database to
understand further the related proteins and transcripts involved in
feeding preferences. At the same time, metabolomics was used to detect
the difference between the two species. Our result provided a profound
understanding of the functions of the different genes about polyphagous
and oligophagous.