• The Plant Pathology Journal
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• 제20권3호
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• pp.212-219
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• 2004

Three isolates of Cucumber mosaic virus (CMV) from lily plants showing mosaic and distortion symptoms were detected by reverse-transcriptase polymerase chain reaction (RT-PCR) using primers specific to Cucumovirus genus namely, LK-CMV, LK4-CMV, and LKS-CMV. Restriction enzymes patterns of the RT-PCR products revealed that the lily isolates belonged to subgroup IA of CMV. In terms of biological properties, the lily isolates have highly similar but distinct pathogenicity as reported in other lily strains and ordinary strains of CMV. To characterize the molecular properties, cDNAs containing coat protein (CP) gene and 3' non-coding region (NCR) of RNA3 for the isolates were cloned and their nucleotide sequences were determined. The CP similarity (218 amino acids) was highly homologous (>97％) with that of subgroup I CMV strains. However, an additional 20-nulcleotide long segment was only present in 3' NCR of lily isolates, which form an additional stem-loop RNA structure. By using chimeric construct exchange cDNA containing 3'NCR of LK-CMV into the full-length cDNA clone of RNA3 of Fny-CMV, this additional segment may prove to be significant in the identification and fitness of the virus in lily plants. The pathology of zucchini squash infected by F1F2L3-CMV, a pseudorecombinant virus was showed to change drastically the severe mosaic and stunting symptom into a mild chlorotic spot on systemic leave, compared with Fny-CMV. To delimit the sequence of RNA3 affected the pathology, various RNA3 chimeras were constructed between two strains of CMV. The symptom determinants of F1F2L3-CMV were mapped to the positions amino acid 234, 239, and 250 in 3a movement protein (MP). RNA3 chimeras changed the sequences encoding three amino acids were resulted in alteration of systemic symptom.

• Journal of Biosystems Engineering
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• 제42권4호
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• pp.314-322
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• 2017

Purpose: This study was conducted to investigate the hot air drying characteristics of squash slices depending on the drying conditions (input air velocity, input air temperature, and sample thickness). Methods: The developed drying system was equipped with a controllable air blower and electric finned heater, drying chamber, and ventilation fan. Squash (summer squash called Korean zucchini) samples were cut into slices of two different thicknesses (5 and 10 mm). These were then dried at two different input air temperatures (60 and $70^{\circ}C$) and air velocities (5 and 7 m/s). Six well-known drying models were tested to describe the experimental drying data. A non-linear regression analysis was applied to determine model constants and statistical indices such as the coefficient of determination ($R^2$), reduced chi-square (${\chi}^2$), and root mean square error (RMSE). In addition, the effective moisture diffusivity ($D_{eff}$) was estimated based on the curve of ln(MR) versus drying time. Results: The results clearly showed that drying time decreased with an increase in input air temperature. Slice thickness also affected the drying time. Air velocity had a greater influence on drying time at $70^{\circ}C$ than at $60^{\circ}C$ for both thicknesses. All drying models accurately described the drying curve of squash slices regardless of slice thickness and drying conditions; the Modified Henderson and Pabis model had the best performance with the highest R2 and the lowest RMSE values. The effective moisture diffusivity ($D_{eff}$) changes, obtained from Fick's diffusion method, were between $1.67{\times}10^{-10}$ and $7.01{\times}10^{-10}m^2/s$. The moisture diffusivity was increased with an increase in input air temperature, velocity, and thickness. Conclusions: The drying time of squash slices varied depending on input temperature, velocity, and thickness of slices. The further study is necessary to figure out optimal drying condition for squash slices with retaining its original quality.

• The Plant Pathology Journal
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• 제19권4호
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• pp.210-216
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• 2003

This study examined the existence of genetically diverse population of Cucumber mosaic virus (CMV), known as quasispecies, from lily, Nicotiana benthamiana and from purified virions. Based on the conserved sequences of CMV lily isolates in intergenic region (IR) on RNA3, the genetic variation of IR from three different sources was investigated by a specific restriction endonuclease hydrolysis of amplified reverse transcription-polymerase chain reaction (RT-PCR) products using virus-specific primers, and was compared with IR sequences. The IR nucleotide sequences of CMV lily isolates were highly conserved, however, quasispecies was detected from all three sources in low level, containing sub-populations of RNA3. These subpopulations of RNA3 were inoculated onto zucchini squash by in vitro transcripts from corresponding full-length cDNA clones together with Eny RNA1 and 2 transcripts. The systemic symptom of zucchini plants infected by these quasispecies was chlorotic spotting, which was milder than severe mosaic and stunt symptom caused by Eny-CMV. The severity of symptom was correlated with RNA accumulation of viruses. These results suggest that the genome of CMV lily isolates consists of quasispecies populations.

• The Plant Pathology Journal
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• 제23권4호
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• pp.245-250
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• 2007

The complete genome sequence of Zucchini yellow mosaic virus stain A (ZYMV-A) isolated from a hollyhock (Althaea rosea) was determined by using RT-PCR with a series of primer sets. The virus genome consisted of 9593 nucleotides (nt), excluding the poly(A) tract at 3' terminus of the virus genome, with 5' and 3' untranslated region of 139 and 211 nt, respectively. The deduced polyprotein of ZYMV-A consisted of 3080 amino acid (aa) residues and was 351 kDa in molecular weight. All proteolytic cleavage sites of the polyprotein of ZYMV-A were compared with those of ZYMV strains, which showed the cleavage sites were conserved among ZYMV strains. The HC-Pro contained the KITC and PTK motifs, and the DAG motif was located at CP ORF of ZYMV-A, suggesting that ZYMV-A is aphid-transmissible. Phylogenetic tree analysis based on the complete genome among ZYMV strains or CP ORFs with other potyviruses showed ZYMV strains formed a distinct group. These results clearly confirmed that ZYMV-A was another distinct strain in ZYMV population at molecular level.

• The Plant Pathology Journal
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• 제18권3호
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• pp.121-125
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• 2002

This study was conducted to determine the causal virus that naturally infected hollyhock (Althaea rosea) plant showing mild mosaic symptom in 1999. Flexuous virus particles were found in the cytoplasm of plant tissue from infected hollyhock under transmissible electron microscopy. A virus from the genus Potyvirus under the family Potyviridae was isolated and was maintained on Chenopodium quinoa for three passages. Chlorotic local legions were used to inoculate 20 species of indicator plants. The virus infected all the tested cucurbit plants, but failed to infect Nicotiana benthamiana. Based on the host range test and RT-PCR analysis, the potyvirus was identified as a strain of Zucchini yellow mosaic virus-A (ZYMV-A), one of the major pathogens of cucurbits. Infectivity analysis showed that ZYMV-A induced faster systemic symptom than ZYMV-Cu on squash and other cucurbit plants, suggesting that ZYMV-A was a more severe strain. To better characterize ZYMV-A, Western blot assay was carried rout to the coat protein (CP) of the virus using ZYMV-specific antiserum with ZYMV-Cu and other potyviruses. The CP of the virus reacted strongly with the antiserum against ZYMV, and other tested antisera did not react with the CP of ZYMV-A. Results strongly suggest that the potyvirus infecting hollyhock was a novel strain of ZYMV. This is the first report on ZYMV as the causal virus infecting hollyhock in Korea.

• 한국미생물·생명공학회지
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• 제43권1호
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• pp.79-83
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• 2015

박과는 스쿼시, 호박, 애호박, 조롱박, 오이 및 수박 등 100여 속이 넘는 속이 포함된 식물과이며, 종자의 수입량이 매우 많은 작물이다. 이들이 우리나라로 수입될 때, 규제바이러스인 Squash mosaic virus (SqMV), Cucumber green mottle mosaic virus (CGMMV) 및 Kyuri green mottle mosaic virus (KGMMV)에 대하여 검역을 수행한다. 본 연구에서는 SqMV, CGMMV 및 KGMMV를 신속·높은 감도로 검출할 수 있는 특이적 RT-PCR 및 nested PCR 프라이머 조합과 유전자변형-양성대조구 플라스미드를 개발하였다. 또한 본 연구에서 개발한 진단시스템을 2010년부터 2014년 상반기까지 현장적용하여, SqMV 47건, CGMMV 67건 및 KGMMV 17건을 검출하였다.

• 식물병연구
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• 제13권1호
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• pp.71-73
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• 2007

전라남도 호박 주산단지의 2000년 바이러스병 발생포장율은 노지재배 76.1%,억제재배 55%,반촉성재배는 발생이 없었으며, 포장별 이병주율은 반촉성재배 3.6%, 노지재배 100%이었다. 포장에서 채집된 시료에 대한 RT-PCR 검정결과 노지재배는 40점 시료 중 WMV 16점, ZYMV 10점, PRSV 2점이 각각 검출되었으며, WMV, ZYMV, PRSV의 2개 또는 3개 바이러스에 중복감염된 시료도 7점이었다. 억제재배는 21점 시료중 WMV 7점, ZYMV 6점, PRSV 6점, WMV와 PRSV의 2개 바이러스에 중복감염된 시료가 1점이었으며, CMV는 검출되지 않았다.

• 생물환경조절학회지
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• 제28권3호
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• pp.185-196
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• 2019

플러그 셀 크기와 육묘일수를 달리하여 '농우'와 '농협' 애호박을 육묘 시 정식에 적합한 묘령을 구명하고자 본 연구를 수행하였다. 플러그 셀 크기에 따른 애호박의 생장에 관한 첫 번째 실험은 침지 후 최아된 종자를 파종한 뒤 32구묘는 본엽이 3-4매 전개된 파종 25일 후, 50구묘는 본엽 2매가 전개된 파종 15일 후, 105구묘는 본엽 전개 직전인 파종 10일 후, 그리고 162구묘는 떡잎이 전개된 파종 8일 후에 각각 정식하였다. 육묘일수에 따른 애호박의 생장에 관한 두 번째 실험은 실험 1의 결과를 기반으로 하여 파종일을 달리하고 정식일을 동일하게 하여 처리 간 차이를 비교하기 위해서 수행하였다. 정식일을 미리 정한 후 처리별로 정식에 필요한 일수를 역산하여 각 처리에 필요한 종자의 파종일을 정하였다. 첫 번째 실험에서 초장은 두 품종 모두 105구에서 가장 컸고, 그 다음으로는 162구, 50구, 32구 순서로 컸다. 과실의 상품성은 가장 높은 값을 보이는 처리가 품종에 따라 달랐으나 32구에서 두 품종 모두 가장 낮았고, 162, 105 및 50구 사이에서는 크게 차이가 나지 않았다. 따라서 105구에서 육묘를 했을 때 32구에 비해 육묘일수를 단축할 수 있고 작은 면적에서도 육묘가 가능하며 정식 시 셀 크기가 작아 작업이 더 효율적이었다. 두 번째 실험에서 정식 시 초장과 엽폭은 32구 묘가 유의적으로 높았으나 4주일 후 초장은 처리들 간에 유의적인 차이가 없어졌고 엽폭은 셀 크기가 작은 처리에서 재배한 묘가 오히려 32구에서 재배한 묘보다 더 컸다. 이는 정식 시부터 셀 크기가 작은 트레이에서 재배된 묘의 경경이 4주일 후까지 유의적으로 높은 값을 보인 것과 연관이 있는 것으로 보인다. '농우' 품종의 경우 첫 수확한 과실의 과장과 과중은 105구 처리에서 가장 컸다. '농협' 품종의 경우 162구 처리에서 과장이 가장 길고 과중이 가장 무거웠고 105구 처리에서도 유사한 값을 보였다.

• 식물병연구
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• 제13권2호
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• pp.82-87
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• 2007

박과 작물에 발생하는 종자전염성 막대형 바이러스인 CGMMV, KGMMV, ZGMMV 3종의 단독 및 동시 VC/RT-PCR 유전자 진단법을 개발하였다. CGMMV 등 3종의 바이러스에 대한 동시진단용 조합선발을 위하여 12조합 중에서 동시 진단용 프라이머 조합 CGMMV-C724, KGMMV-K513, ZGMMV-Z407A를 선발하였다. CGMMV등 3종에 대한 triplex VC/RT-PCR 유전자 진단법은 박, 수박, 오이, 멜론, 쥬키니 호박, 애호박, 담배(N. benthamiana) 작물의 식물체 즙액과 프라이머 간에 간섭현상 없이 특이적으로 진단되었다.

• The Plant Pathology Journal
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• 제23권4호
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• pp.251-259
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• 2007

Two isolates of Cucumber mosaic virus (CMV) originated from lily plants, named Ly2-CMV and Ly8-CMV, were compared with their pathological features in several host plants. Ly2-CMV and Ly8-CMV could induce systemic mosaic symptom in Nicotiana benthamiana, but Ly2-CMV could not systemically infect tomato and cucumber plants that have been used for CMV-propagative hosts. While Fny-CMV used as a control infected systemically the same host plants, producing typical CMV symptoms. Ly8-CMV could infect systemically two species of tobacco (N. tabacum cv. Xanthi-nc and N. glutinosa) and zucchini squash (Curcubita pepo), but Ly2 failed systemic infection on these plants. As resulted from tissue-print immunoblot assay, different kinetics of systemic movement between Ly2-CMV and Ly8-CMV were crucial for systemic infection in tobacco (cv. Xanthi-nc). Sequence analysis of full-length genome of two lily isolates showed Ly2 and Ly8 belonged to subgroup IA of CMV. The lily isolates shared overall 98 % sequence identity in their genomes. Coat protein, 3a protein, and 2b protein involved in virus movement was highly conserved in genomes of the isolates Ly2 and Ly8. Although there is the low frequency of recombinants and reassortants in natural CMV population, phylogenetic analysis of each viral protein among a number of CMV isolates suggested that genetic variation in a defined population of CMV lily isolates was stochastically produced.