A survey of plant-parasitic nematodes (PPNs) was carried out in medicinal crop cultivated fields from July to August in 2023. Three-leaf ladybell, Adenophora triphylla var. japonica is a highly valued medicinal plant that is used to treat or prevent bronchitis, cough, cancer, and obesity in Korea. A. triphylla plants with small root-galls were observed in a field of Yeongju Agricultural Technology Center, which were identified as a root-knot nematode. Additional morphological and molecular analyses studies were performed and identified as Meloidogyne hapla, Northern root-knot nematode. Population densities of M. hapla ranged from 20~30 nematodes per 100 cm3 of soil. M. hapla was detected at lower densities in soil compared to other infected host crops, but there are concerns about damage to M. hapla since A. triphylla is cultivated for more than two years once planted. Our results indicate that A. triphylla roots damage by M. hapla were identifed, it is necessary to prepare control methods such as registration of applicable nematicides and crop rotation.
약용작물인 천궁류를 가해하는 총채벌레류의 발생종을 확인하고자 2018년 7월과 8월 2회에 걸쳐 영주와 봉화의 일천궁과 토천궁 재배지에서 채집하였다. 두 재배지에서 총 5종의 총채벌레류가 발생함을 확인하였고 꽃노랑총채벌레 > 대만꽃노랑총채벌레 > 미나리총채벌레 > 볼록총채벌레 > 대관령총채벌레 > 파총채벌레 순으로 동일하였지만 포획비율에서는 약간의 차이를 보여 주었다. 이러한 결과는 약용작물로 재배하고 있는 2종의 천궁에서 우점종이 꽃노랑총채벌레와 대만총채벌레임을 확인시켜 주었다. 또한 미나리총채벌레와 대관령총채벌레가 천궁류에서 서식하고 있음을 처음 확인하였다.
오미자를 가해하는 여러 해충 중 과피를 가해하는 볼록총채벌레를 대상으로 황색등에 대한 기피반응과 유인제에 대한 유인반응을 2017년 5월부터 8월까지 경북 문경시 동로면 소재 유기전환, 무농약, GAP 및 유기농 재배지에서 조사하였다. 황색등을 처리한 평지 및 경사지 모두에서 볼록총채벌레의 기피반응을 확인할 수 없었고 꽃노랑총채벌레 의 유인제로 사용하고 있는 p-anisic acid methyl ester에 대한 유인반응 또한 대조구와 비교했을 때 효과가 없는 것으로 조사되었다. 이러한 결과는 Derksen et al. (2016)이 언급한 것처럼 볼록총채벌레가 주행성(diurnal) 해충임을 의미하며 p-anisic acid methyl ester가 아닌 오미자가 발산하는 다른 향기물질(plant violates)을 이용한 유인제나 수컷이 방출하는 집합페로몬을 활용한 트랩 개발이 필요함을 제시하고 있다. 이러한 트랩 개발은 볼록총채벌레의 효과적인 예찰 및 대량포획에 도움이 될 것으로 판단된다.
Two Grapholita congener, G. molesta and G. dimorpha have difference in several biological characters such as flight time, emerging number/year, damage site, pupation site, and mating time although their host plants were similar. As a problem, cross-trapping was identified in each trap for monitoring. Effects on species-specific lure using minor sex pheromone components were observed in host plant orchards (apple, pear, peach, and plum) for continuative two years. Treatments of various ratios (0 to 10%) of Z8-12OH to G. molesta lure (Z8-12Ac/E8-12Ac = 95:5) allowed to increase the attraction of G. molesta, but not of G. dimorpha male. Other two minor components (14Ac and 12Ac) to G. dimorpha lure (Z8-12Ac/E8-12Ac = 85:15) were not showed species-specific responses. However, 10% treatment of Z8-14Ac to G. dimorpha lure was showed that G. molesta was decreased significantly although G. dimoprha was not affected. E8-14Ac treatment to new G. dimorpha lure (Z8-12Ac/E8-12Ac/Z8-14Ac = 85:15:10) not affected to attraction of two species. From these results, we suggest that optimum ratios for species-specific monitoring of G. molesta and G. dimorpha are Z8-12Ac/E8-12Ac/Z8-12OH = 95:55:5 and Z8-12Ac/E8-12Ac/Z8-14Ac = 85:15:10, respectively.
The pheromone biosynthesis in Plutella xylostella is more active in the scotophase than in the photophase, which suggests that there may be changes of gene expression in the pheromone glands. To identify genes contributing to change in pheromone production, we analyzed transcriptomes from pheromone glands of both decapitated females in the photophase and normal ones in the scotophase. Comparative analysis were performed with transcriptomes of pheromone glands from non-decapitated (PG) females and decapitated ones for identification and expression of putative genes associated with pheromone biosynthesis pathway. Deep sequencing for mRNAs in the pheromone gland yielded approximately 7.5Gb and totally 17265 transcript were constructed under a homology cutoff of 10-6 Evalue. Genes putatively involved in pheromone biosynthesis were identified such as acetyl-CoA carboxylase, acetyl-CoAdehydrogenase, fatty acid synthase (FAS), desaturases (Δ9 and Δ 11) and fatty acid reductases (FAR) including pgFAR, alcohol oxidase, aldehyde oxidase and aldehyde reductase, etc. Expression of 6 signal genes involving in pheromone biosynthesis such as acyl-CoA desaturase, FAR, PBAN receptor, fatty acid transporter, acyl-CoA binding protein did not exhibited ant significant different in both transcriptomes. Quantitative RT-PCR revealed that expressions of FAS, Δ11 desaturase and pgFAR were higher in PG than that in ΔPG. Based on results, Δ11 desaturase and pgFAR may have a crucial role in sex pheromone biosynthesis of P. xylostella.
After firstly identified sex pheromone components of Bombxy mori, those of many insect pests were synthesized by organic chemistry methodology. These synthesized components were used for monitoring, mass trapping, and mating disruption during five decades. For identification of pheromone biosynthesis mechanisms and control to many pests bring to serious damages also were proceeded. The transcriptome analysis from pheromone glands by Next Generation Sequence (NGS) showed many genes and pathway involved on sex pheromone biosynthesis.. The two main genes involved on production of acetate and alcohol, and aldehyde from fatty acid, fatty acid desaturase and fatty acid reductase (FAR) were identified and functional characterized via gene introduction to Brewer’s yeast Saccharomyces cerevisiae. This S. cerevisiae now used as a mediator as well as cell factory for sex pheromone producing. Recently, One group was published that the plant factory for producing via genetically modified plant (tobacco, Nicotiana benthamiana) as a step of semisynthetic preparation. These trials will be suggest that firstly, the possibility of yeast as a molecular toolbox to produce pheromone components and secondly, a novel and cost-effective way of producing moderate to large quantities of pheromones with high purity and a minimum of hazardous waste.
Postharvest insect pest control is highly demanding in agricultural industry including domestic consumer markets and exporting products for a quarantine purpose. Especially, the organic or environmentally friendly agricultural products do not fit to the traditional chemical postharvest treatments using methyl bromide (MeBr) or phosphine (PH3). As an alternative, a physical treatment called CATTS (controlled atmosphere and temperature treatment) has been developed to control various insect and mite pests on ornamental products. The oriental fruit moth, Grapholita molesta, infects the apple or pear fruits and is limited in importing and exporting the infected products. To apply CATTS on this insect pests, the most heat-tolerant stage was determined. Among the immature stages locating on the fruits, the fifth instar larvae were the most tolerant to 44℃ for 20 min. A ramping step of CATTS is to increase chamber temperature from 25℃ to 46℃ under 15% CO2 and less than 1% O2. The ramping rate was positively correlated with the CATTS efficiency. After the ramping step, the duration of CATTS was positively correlated with CATTS efficiency. However, fruit damage by CATTS was negatively correlated with the ramping rate was positively correlated with the CATTS duration. in addition, the CATTS efficiency was highly dependent on the fruit internal temperature at 44℃. From all these parameters, we developed a standard protocol yielding 100% control efficiency of CATTS.
The oriental fruit moth (Grapholita molesta) and the plum fruit moth (G. dimorpha) share the same major sex pheromone components, Z8-dodecenyl acetate (Z8-12Ac) and E8-dodecenyl acetate (E8-12Ac) with different ratio. However, these two congener male species were cross-attracted to the counter sex pheromone traps. For development of the specific monitoring lures, the minor sex pheromone components were added to the major components. G. molesta females emit two minor components of Z8-12OH and 12OH and G. dimorpha females emit four minor of 12Ac, 14Ac, Z8-14Ac, and E8-14Ac. For a specific monitoring lure of G. molesta, only Z8-12Ac major component attracted only G. molesta males, but did not any G. dimorpha. For a specific monitoring lure of G. dimorpha, the addition of Z8-14Ac to the major component (Z8-12Ac:E8-12Ac = 85:15) attracted G. dimorpha males with less than 5% G. molesta males. Other with components (12Ac, 14Ac, and E8-14Ac) was not effective in both trapping efficiency and selectivity.
Two Grapholita congeners, G. dimorpha and G. molesta, are internal fruit feeders and their young larvae cause serious damages to pome and stone fruits in Korea. They share similar morphological and biological characters not to be easily discriminated. We needed to develop molecular markers using diagnostic primers and PCR-RFLP with specific sequences in ND4 region. Two species have similar sex pheromone components (Z8-12:Ac and E8-12:Ac) although their composition ratios are different. In fields, G. molesta males were more captured in lures with higher Z8 component ratio than G. dimorpha males. Addition of Z8-12OH, minor sex pheromone component prevented G. dimorpha from capturing G. molesta males. In electroantennogram (EAG) bioassay, these two species males showed significant electric responses in their own sex pheromone ratios. An addition of Z8-12:OH to the major sex pheromone components significantly suppressed the EAG response of G. dimorpha, while it did not change that of G. molesta. A deep sequencing analysis of transcripts of both species pheromone glands identified sex pheromone biosynthesis genes including fatty acid synthase, desaturases, fatty acyl reductase (FAR), and aldehyde reductase. The presence of delta 10 desaturase in both species suggests that a double bond at C8 position in dodecenyl acetate is produced by desaturation at C10 position of tetradecenyl fatty acid and subsequent β-oxidation, which is then reduced at carboxylic acid by FAR to be acetylated by acetyl transferase. High sequence variation of FAR genes of G. molesta and G. dimorpha suggests their stereoisomer substrate preference, which may exert a driving force for this speciation with delta 10 desaturase.
The oriental fruit moth (Grapholita molesta) and the plum fruit moth (G. dimorpha) are internal feeders of stone and pome fruits and highly similar in morphological characters and feeding behaviors. These two species share their two main sex pheromone components, Z8-dodecenyl acetate(Z8-12Ac) and E8-dodecenyl acetate(E8-12Ac) although pheromone compositions are different. But, two males of these species were cross-attracted to G. molesta and G. dimorpha pheromone trap, respectively. Their host plants are also very similar in Rosaceae including apples, plums, paches, etc. These sympatric and similar pheromone ratios and biological characters suggest their recent speciation divergence. To determine genetic origin of this speciation, were analysed transcriptomes associated in sex pheromone biosynthesis in these sibling species. Total RNAs were collected from pheromone glands and read by a short read deep sequencing technology using an lllumina HiSeq2000. Almost 3-4 Gb reads were de novo assembled and resulted in 76,361 contigs of G. dimorpha and 104,463 contigs of G. molesta. More than 70% of these contigs were annotated and classified by a typical GO analysis. Transcriptomes related with sex pheromone biosynthesis were selected and grouped into fatty acid synthase, fatty acid oxidation, desaturase, reductase, and isomerase. These analyses identified sex pheromone biosynthesis machineries, which showed significant differential expressions between two sibling species. Field monitoring assays indicated the minor components (Z8-12OH) resulted from fatty acid reductase were crucial in isolating two sibling species.
The oriental fruit moth (Grapholita molesta) and the plum fruit moth (G. dimorpha) are internal feeders of apples. Their sympatric and similar sex pheromone compositions suggest their recent divergence in speciation. This study aims to determine genetic factors in this speciation by comparing transcriptomes associated in sex pheromone biosynthesis in these sibling species. Total RNAs were collected two female abodominal tips and read by a short read deep sequencing technology using an lllumina HiSeq. Almost 3-4 Gb reads were de novo assembled and resulted in 76,361 contigs of G. dimorpha and 104,463 contigs of G. molesta. More than 70% of these contigs were annotated and classified by a typical GO analysis. Transcriptomes related with sex pheromone biosynthesis were selected and grouped into fatty acid synthase, fatty acid oxidation. These analyses identified sex pheromone biosynthesis machineries
Three tortricid pests, Grapholta dimorpha (Komai), G. molesta (Busck), and Carposina sasakii (Matsumura) are known as internal apple feeders in Korea. For identify young larvae which occurring serious damage in fruits, the molecular maker was developed from their mitochondrial DNA (mtDNA) sequences. To develop of PCR-RFLP marker, ND4 locus was digested with Swa Ⅰ. ND4-Swa Ⅰ digests showed two bands (396, 292 bp), one band (700 bp), and three bands (408, 178, and 103 bp) of G. dimorpha, G. molesta, and C. sasakii, respectively. Species-specific diagnostic PCR primers were developed in the ND4 locus and gave species-specific PCR products. Finally, these markers were applied to diagnose larvae infesting apples and showed species-specific fruit damage patterns, in which most feeders of G. dimorpha, G. molesta, and C. sasakii showed major feedings in apex, surface, and core of apple fruits, respectively.
Three insect pests internally feed pome fruits in Korea. These include oriental fruit moth (Grapholita molesta), plum fruit moth (Grapholita dimorpha) and peach fruit moth (Carposina sasakii). Molecular markers discriminating these three species were developed using PCR-RFLP technique. Mitochondrial (mt) genomes were analyzed to locate polymorphic loci. Six mtDNA regions (CO-Ⅰ, CO-Ⅱ, CB, 16SrRNA-12SrRNA, ND3, ND4) of G. dimorpha were cloned and sequenced. These six sequences of G. dimorpha were aligned with those of C. sasakii and G. molesta to determine polymorphic restriction sites. Predicted PCR-RFLP markers were confirmed with known insect samples. With the validated PCR-RFLP markers, field male adults collected in traps baited with rubber sept lures impregnated with different ratios of major sex pheromone components of G. molesta were analyzed.