We found ten species of larvae belonging to the family Pleuronectidae as a result of analysis on ichthyoplankton collected monthly from the East Sea, Yellow Sea, Korea Strait and East China Sea between February 2016 and May 2018 using bongo net. The ten species of pleuronectid larvae were divided into three groups in morphology. Group A had three or four bars on the lateral side of the tail: Glyptocephalus stelleri, G. kitaharae, Pseudopleuronectes yokohamae, and Hippoglossoides dubius. Group B had a row of melanophores along the dorsal and ventral side of tail: Cleisthenes pinetorum, Eopsetta grigorjewi, Dexistes rikuzenius, and Platichthys bicoloratus. Group C had dense melanophores which are covering trunk and tail entirely except caudal peduncle: Platichthys cornutus and Platichthys japonicus. The three groups did not associate with previous molecular phylogenetic studies except for the G. stelleri and G. kitaharae of the group A.

Myosin is considered as the vital motor protein in vertebrates and invertebrates. Our present study was conducted to decipher the occurrence of myosin in dog fish (Squalus mitsukurii). We isolated one clone containing 979 bp cDNA sequence, which consisted of a complete coding sequence of 453 bp and a deduced amino acid sequence of 150 amino acids from the open reading frame with molecular weight, isoelectric point and aliphatic index are 16.72 Kda, 4.49 and 78.00, respectively. It contained 428 bp long 3' UTR with single potential polyadenylation signals (AATAAA). The predicted EF CA2+ binding domains were identified in residue 6-41, 83-118 and 133-150. A BLAST search indicates this protein exhibits a strong similarity to whale shark (Rhincodon typus) MLC3 (91% identical) and also house mouse (Mus musculus) MLC isoform 3f (81% identical). Phylogenetic analysis revealed that this protein is a MLC 3 isoform like protein. This protein also demonstrates highly conserved region with other myosin proteins. Homology modeling of S. mitsukuri was performed using crystal structure of Gallus gallus skeletal muscle myosin II based on high similarity. Reverse transcription-polymerase chain reaction (PCR), quantitative PCR results exhibits dogfish myosin protein is highly expressed in muscle tissue.

The genus Aphidius is one of the largest groups of aphid parasitoids. Aphidius colemani is most common and commercially available for the aphid control. Recently, the mummies of Rhopalosiphum padi were collected from barley banker plants in Yecheon. Nucleotide sequence analysis identified its parasitoid as A. transcaspicus, which is morphologically similar to A. colemani. Interspecific variation of both COI and ITS2 between two species was 5.13 and 10.73%, respectively. Intraspecific variations of both COI and ITS2 of A. transcaspicus was 1.85 and 4.96%, respectively. We assume the barley banker plants for A. colemani were contaminated by A. transcaspicus. Thus, precise identification of natural enemies is required for more effective pest control.

In abalones, interspecific hybridization has been suggested as a possible means to increase production and desired traits for the industry. In Korea, Haliotis gigantea is considered a species with a larger size and higher temperature tolerance than H. discus hannai. However, H. discus hannai is considered the most valuable and popular fishery resource due to its better acceptance and higher market prices. Thus, viable interspecific hybrids have been produced by artificial inseminating H. gigantea eggs with H. discus hannai sperm. However, the reciprocal hybrid cross was not successful. In this study, the hybridity and the growth and thermal tolerance performance of the interspecific hybrids were examined. A combination of various assays revealed maximum growth occurrence at 21℃ and the higher growth rate in the hybrids than that of H. discus hannai parent. In addition, the growth and survival at high-temperature (28℃) of the hybrids was equivalent to that of the highly tolerant H. gigantea parent, suggesting new possibilities to overcome the mass mortality in H. discus hannai during high temperature periods of summer season in Korea. Furthermore, the induced interspecific hybrid status was confirmed by the presence of species-specific bands for each parental species of the random amplified polymorphic DNA (RAPD) profiles using universal rice primer (URP), which could be used as speciesspecific markers to distinguish the hybrids and their parental species.

Aphidius colemani has been used as commercially available natural enemies for the aphid control. However, some siblingspecies are difficult to distinguish their morphology even though they have different parasitic characteristics. Recentlywe identified overwintering parasitoids inside the aphid mummies at the pepper greenhouse in Yecheon. The nucleotidesequence analysis identified as A. transcaspicus which is morphologically similar with A. colemani. Those genetic differencesof COI and ITS2 sequences were 4.36-4.84% and 2.65-5.84%, respectively. While A. colemani is useful for the controlof Aphis gossypii and Myzus persicae, A. transcaspicus parasitize various species belongs to the genera Hyalopterus, Melanaphisand Rhopalosiphum. Thus, precise diagnosis of natural enemies is required for the successful pest control.

Insect resistance to crop protecting chemicals is developing very rapidly, which is a major problem in the production of crops. Recently, the mechanism of resistance to various pseticides s has been revealed in Helicoverpa armigera. However, to date, no technology has been developed to quickly diagnose resistance yet. In this study, we present the results of developing method of rapid diagnosis of resistance