본 논문에서는 유통 농산물 잔류농약 부적합 현황 분석을 위하여 네트워크 분석 기법을 적용하였다. 분석용 데이터는 『2017년도 식품안전관리지침』내 “유통농산물별 잔류농약 부적합 현황”을 참고하였으며, 주요 분석 기법 으로는 중심성 분석(연결정도 중심성, 근접 중심성, 매개 중심성)을 적용하였다. 연결정도 중심성 분석결과 chlorpyrifos와 diazinon에서 “연결된 노드”가 가장 많은 것으로 확인되었다. 근접 중심성에서는 19종을 제외한 농약성분들 사이에서 유사한 정도를 보여주고 있었다. 매개 중심 성 분석 결과에서는 fluioxonil과 chlorpyrifos가 가장 높은 경향을 보여주어 이들이 농약성분 네트워크에서 “가교” 역 할을 수행 하는 것으로 파악되었다. 네트워크 분석 결과, 기존의 통계분석을 통해서는 분석 할 수 없었던 농약성분 들 사이의 “관계” 데이터를 확인 할 수 있었다. 향후 이러한 분석기법은 최적화/정교화 과정을 통해서 보다 정밀하게 농약성분 부적합 현황 분석을 위한 도구로서 적용되리라 기대한다.

We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the properties of the pitches. As the hydrogen pressure increased, the C/H ratio decreased, and the solubility in n-hexane increased. The mesophase pitch with entirely anisotropic domains of flow texture exhibited good meltspinnability. The mesophase carbon fibers obtained from the catalytically hydrogenated petroleum residue showed moderate mechanical properties.

The green peach aphid (Myzus persicae) is a cosmopolitan pest of agricultural and horticultural crops and causes serious economic damages. M. persica has rapidly developed resistance to a wide variety of insecticides, including pyrethroids. Target site insensitivity mechanism mediated by two mutations (L1014F and M918T) on the para-type voltage-sensitive sodium channel (vssc) is mainly responsible for pyrethroid resistance. To predict the vssc resistance allele frequency, quantitative sequencing (QS) protocol was established. Frequency prediction equations generated from the plots of signal ratios and amplification critical time showed a high correlation coefficient (r2>0.993), indicating its high accuracy in prediction. QS results revealed that the kdr-type L1014F mutation is only present in Pyeongchang strain. No field strains of M. persicae possessed the super-kdr type M918T mutation. However, a novel M918L mutation was found by genotyping approach. The allele frequencies of M918L and L1014F were 0% to 53% in populations examined, and the level of M918L mutation frequency was closely related with pyrethroid resistance. Therefore, QS-based detection of M918L mutation frequency should faciltate the monitoring of pyrethroid resistance in the field.

The green peach aphid (Myzus persicae) is a serious pest of agricultural and horticultural crops all over the world. M. persica has rapidly developed resistance to a wide variety of insecticides, including carbamates. The E4/FE4 carboxylesterase is known to be involved in carbamate resistance. To compare the E4/FE4 carboxylesterase gene copy number, as a genetic resistance marker, between seven field strains, quantitative real-time PCR (qPCR) was performed. In addition, quantitative sequencing (QS) was employed to predict the frequencies of acetylcholinesterase (AChE) mutations (A301S and S431F) that are associated with target site insensitivity. All M. persica strains examined possessed the S431F mutation in the heterozygous state except for a susceptible strain, implying the possibility of AChE duplication. In contrast, no A301S mutation was found. Frequency prediction equation was generated from the plots of signal ratios and amplification critical time, which showed a high correlation (r2>0.996). QS analysis of M. persicae populations revealed that the allele frequency of S431F ranged 4% to 63%. Taken together, the AChE resistance allele frequencies determined by QS and the E4/FE4 gene copy number by qPCR should facilitate the detection and monitoring of carbamate resistance in M. persicae in the field.

A new vegetable peanut variety “Bakjung(Arachis hypogaea L.)” was developed from the cross between Shindaekwang and Suwon94 at the Honam Agricultural Research Institute and Yongnam Agricultural Research Institute, National Institute of Crop Science in 200