바이러스 무병묘 정식시기 및 재배기간이 씨고구마 수량에 미치는 영향

남상식,유경단,이형운,고산,이승용,이경보,강용구,양정욱 한국국제농업개발학회 2019 韓國國際農業開發學會誌 Vol.31 No.3

Sweet potato is a vegetative propagation crop, and if the same seed sweet potato cultivates for the long term, the yield and quality of sweet potato decrease due to intensified virus infection. Recently, the demand for virus-free sweet potato seedlings has been increasing to the farmers, but the production and supply of virus-free seedlings are insufficient in Korea. Therefore, we investigated the yield of virus-free seed sweet potato in different planting time and cultivation period. Proliferated seedlings derived from meristem culture was examined in this experiment. For planting time 4 varieties (‘Shinyulmi’, ‘Jinhongmi’, ‘Pungwonmi’, ‘Hogammi’) and for cultivation period 3 varieties (‘Shinyulmi’, ‘Pungwonmi’, ‘Hogammi’) were used. Plants were planted in late May, mid-June, and early July in 2015 and 2016. The cultivation period was analyzed when harvested at 110, 120, and 130 days after planting in mid-May in 2017 and 2018. Virus infection rates were determined by RT-PCR using pre-harvest leaves. The yield of 100~300 g tuber size suitable for seed sweet potato was increased in all four varieties cultivated in June. Although late planting in early July, produced 1,799~2,043 kg 10a-1 except 1,390 kg 10a-1 of ‘Dahomi’. ‘Pungwonmi’ and ‘Hogammi’ cultivar showed a higher yield of seed sweet potato in the longer cultivation period. The infection rate of SPLCV on ‘Dahomi’ was 13.3% in May and 6.7% on ‘Pungwonmi’ in June 2016. ‘Jinhongmi’ and ‘Dahomi’ infected with SPFMV was 6.7% and 13.3% in May and ‘Shinyulmi’ was 6.7% in June 2016. In the future, we hope to cultivate seed sweet potato produced by virus-free seedling cultivation year by year and investigate the yield and virus infection level to set up the seed sweet potato renewal cycle. 남부지역에서 고구마 바이러스 무병묘의 정식시기 및 재배기간에 따른 괴근 수량 및 씨고구마 생산량을 조사한 결과는 다음과 같다. 1. 바이러스 무병묘 정식시기에 따라 씨고구마로 사용하기에 알맞은 100~300 g 크기의 괴근 생산량은 6월 중순 정식재배에서 ‘신율미’ 2,364 kg/10a, ‘풍원미’ 2,625 kg/10a 수준이었다. 2. 바이러스 무병묘를 7월 상순에 정식하여 재배하여도 씨고구마로 사용하기에 알맞은 100~300 g 크기의 괴근 수량은‘신율미’ 2,043, ‘진홍미’ 1,799, ‘다호미’ 1,390, ‘풍원미’ 1,985 kg/10a 정도가 생산되었다. 3. 고구마 바이러스 무병묘 정식 후 110일, 120일, 그리고 130 일 재배 시 씨고구마 수량은 ‘풍원미’ 1,605, 1,907, 1,834 kg/ 10a, ‘호감미’ 1,816, 1,771, 2,137 kg/10a 수준으로 생산되었다. 4. 수확 전 채취한 고구마 잎에서 SPLCV, SPFMV, SPVG, SPLV 등 4종 바이러스 이병 정도를 검정한 결과 정식시기, 재배기간 등 품종에 따라 약간 차이는 있으나 낮게 검출되어다음해 씨고구마 종자로 문제가 없다고 판단하였다. 5. 바이러스 무병묘 대량 증식에는 시설과 노력이 많이 소요되고 증식량이 적어 면적 확대에 어려움이 있기 때문에 무병씨고구마를 생산하면 면적 확대에 유리하다. 무병묘가 소량일 경우는 계속 증식하면서 7월 상순까지 본밭에 정식하여도씨고구마 생산이 가능하였다. 금후에는 무병묘로 생산한 연차간 씨고구마에 대해 품종별 수량과 품질 평가 후 씨고구마의적정 갱신 주기를 설정하고자 한다.

The Current Incidence of Viral Disease in Korean Sweet Potatoes and Development of Multiplex RT-PCR Assays for Simultaneous Detection of Eight Sweet Potato Viruses

Kwak, Hae-Ryun,Kim, Mi-Kyeong,Shin, Jun-Chul,Lee, Ye-Ji,Seo, Jang-Kyun,Lee, Hyeong-Un,Jung, Mi-Nam,Kim, Sun-Hyung,Choi, Hong-Soo The Korean Society of Plant Pathology 2014 Plant Pathology Journal Vol.30 No.4

Sweet potato is grown extensively from tropical to temperate regions and is an important food crop worldwide. In this study, we established detection methods for 17 major sweet potato viruses using single and multiplex RT-PCR assays. To investigate the current incidence of viral diseases, we collected 154 samples of various sweet potato cultivars showing virus-like symptoms from 40 fields in 10 Korean regions, and analyzed them by RT-PCR using specific primers for each of the 17 viruses. Of the 17 possible viruses, we detected eight in our samples. Sweet potato feathery mottle virus (SPFMV) and sweet potato virus C (SPVC) were most commonly detected, infecting approximately 87% and 85% of samples, respectively. Furthermore, Sweet potato symptomless virus 1 (SPSMV-1), Sweet potato virus G (SPVG), Sweet potato leaf curl virus (SPLCV), Sweet potato virus 2 ( SPV2), Sweet potato chlorotic fleck virus (SPCFV), and Sweet potato latent virus (SPLV) were detected in 67%, 58%, 47%, 41%, 31%, and 20% of samples, respectively. This study presents the first documented occurrence of four viruses (SPVC, SPV2, SPCFV, and SPSMV-1) in Korea. Based on the results of our survey, we developed multiplex RT-PCR assays for simple and simultaneous detection of the eight sweet potato viruses we recorded.

The Current Incidence of Viral Disease in Korean Sweet Potatoes and Development of Multiplex RT-PCR Assays for Simultaneous Detection of Eight Sweet Potato Viruses

곽해련,김미경,신준철,이예지,서장균,이형은,정미남,김선형,최홍수 한국식물병리학회 2014 Plant Pathology Journal Vol.30 No.4

Sweet potato is grown extensively from tropical to temperateregions and is an important food crop worldwide. In this study, we established detection methodsfor 17 major sweet potato viruses using single and multiplexRT-PCR assays. To investigate the current incidenceof viral diseases, we collected 154 samples of varioussweet potato cultivars showing virus-like symptomsfrom 40 fields in 10 Korean regions, and analyzed themby RT-PCR using specific primers for each of the 17viruses. Of the 17 possible viruses, we detected eight inour samples. Sweet potato feathery mottle virus (SPFMV)and sweet potato virus C (SPVC) were most commonlydetected, infecting approximately 87% and 85% ofsamples, respectively. Furthermore, Sweet potato symptomlessvirus 1 (SPSMV-1), Sweet potato virus G (SPVG),Sweet potato leaf curl virus (SPLCV), Sweet potato virus2 ( SPV2), Sweet potato chlorotic fleck virus (SPCFV),and Sweet potato latent virus (SPLV) were detectedin 67%, 58%, 47%, 41%, 31%, and 20% of samples,respectively. This study presents the first documentedoccurrence of four viruses (SPVC, SPV2, SPCFV, andSPSMV-1) in Korea. Based on the results of our survey,we developed multiplex RT-PCR assays for simple andsimultaneous detection of the eight sweet potato viruseswe recorded.

Virus Incidence of Sweet Potato in Korea from 2011 to 2014

김재덕,양정욱,곽혜련,김미경,서장균,정미남,이향언,이경보,남상식,김창석,이관석,김정수,이석찬,최홍수 한국식물병리학회 2017 Plant Pathology Journal Vol.33 No.5

A nationwide survey was performed to investigate the current incidence of viral diseases in Korean sweet potatoes for germplasm and growing fields from 2011 to 2014. A total of 83.8% of the germplasm in Korea was infected with viruses in 2011. Commercial cultivars that were used to supply growing fields were infected at a rate of 62.1% in 2012. Among surveyed viruses, the incidence of five Potyvirus species that infect sweet potato decreased between 2012 and 2013, and then increased again in 2014. Representatively, the incidence of Sweet potato feathery mottle virus (SPFMV) was 87.0% in 2012, 20.7% in 2013 and then increased to 35.3% in 2014. Unlike RNA viruses, DNA viruses were shown to decrease continuously. The incidence of Sweet potato leaf curl virus (SPLCV) was 5.5% in 2003, 59.5% in 2011, and 47.4% in 2012. It then decreased continuously year by year to 33.2% in 2013, and then 25.6% in 2014. While the infection rate of each virus species showed a tendency to decline, the virus infection status was more variable in 2013 and 2014. Nevertheless, the high rate of single infections and mixed infection combinations were more variable than the survey results from 2012. As shown in the results from 2013, the most prevalent virus infection was a single infection at 27.6%, with the highest rate of infection belonging to sweet potato symptomless virus-1 (SPSMV-1) (12.9%). Compared to 2013, infection combinations were more varied in 2014, with a total of 122 kinds of mixed infection.

Virus Incidence of Sweet Potato in Korea from 2011 to 2014

Kim, Jaedeok,Yang, Jung wook,Kwak, Hae-Ryun,Kim, Mi-Kyeong,Seo, Jang-Kyun,Chung, Mi-Nam,Lee, Hyeong-un,Lee, Kyeong-Bo,Nam, Sang Sik,Kim, Chang-Seok,Lee, Gwan-Seok,Kim, Jeong-Soo,Lee, Sukchan,Choi, Hon The Korean Society of Plant Pathology 2017 Plant Pathology Journal Vol.33 No.5

A nationwide survey was performed to investigate the current incidence of viral diseases in Korean sweet potatoes for germplasm and growing fields from 2011 to 2014. A total of 83.8% of the germplasm in Korea was infected with viruses in 2011. Commercial cultivars that were used to supply growing fields were infected at a rate of 62.1% in 2012. Among surveyed viruses, the incidence of five Potyvirus species that infect sweet potato decreased between 2012 and 2013, and then increased again in 2014. Representatively, the incidence of Sweet potato feathery mottle virus (SPFMV) was 87.0% in 2012, 20.7% in 2013 and then increased to 35.3% in 2014. Unlike RNA viruses, DNA viruses were shown to decrease continuously. The incidence of Sweet potato leaf curl virus (SPLCV) was 5.5% in 2003, 59.5% in 2011, and 47.4% in 2012. It then decreased continuously year by year to 33.2% in 2013, and then 25.6% in 2014. While the infection rate of each virus species showed a tendency to decline, the virus infection status was more variable in 2013 and 2014. Nevertheless, the high rate of single infections and mixed infection combinations were more variable than the survey results from 2012. As shown in the results from 2013, the most prevalent virus infection was a single infection at 27.6%, with the highest rate of infection belonging to sweet potato symptomless virus-1 (SPSMV-1) (12.9%). Compared to 2013, infection combinations were more varied in 2014, with a total of 122 kinds of mixed infection.

RNAi-based transgene conferred extreme resistance to the geminivirus causing apical leaf curl disease in potato

Garima Tomar,S. K. Chakrabarti,Nitya Nanda Sharma,A. Jeevalatha,S. Sundaresha,Kanika Vyas,Wamik Azmi 한국식물생명공학회 2018 Plant biotechnology reports Vol.12 No.3

Potato apical leaf curl disease is an emerging geminiviral disease in tropics and subtropics. It was reported for the first time in the year 1999 in northern plains of India but quickly spread to almost all potato growing regions of the country largely due to prevalence of warmer weather during early crop growth, thereby favoring whitefly vector. The problem of apical leaf curl disease in India became more severe due to lack of seed indexing for this virus in conventional seed production scheme. Although it accounts for major yield loss, there is no conventional source of resistance available in potato against Tomato Leaf Curl New Delhi Virus-Potato (ToLCNDV-Potato) that causes this disease in potato. In the present study, we have investigated the potential use of RNAi for obtaining resistance against this DNA virus in potato. The replication-associated protein gene (AC1) of the virus was used to obtain pathogen-derived resistance. The AC1 gene was PCR amplified from field-infected potato leaves, cloned and sequenced (JN393309). It showed 93% sequence similarity with the AC1 gene of Tomato Leaf Curl Virus-New Delhi (TOLCV-NDe; DQ169056) virus. Transgenic plants encoding the AC1 gene in three different orientations, viz. sense, antisense and hairpin loop, were raised. Transgenic lines when challenge inoculated with ToLCNDV-Potato showed different levels of resistance for all three constructs. Transgene integration and copy number in selected transgenic lines were determined by qPCR and further confirmed by Southern blot analysis. Though a reduction in viral titer was observed in transgenic lines encoding either antisense or hairpin loop constructs of AC1 gene, the latter transgenics showed most significant results as shown by reduction in the level of symptom expression in glasshouse screening as well as real-time data of in vivo virus concentration. In fact, we obtained a few totally asymptomatic transgenic lines with hairpin loop strategy.

Validation of reference genes for quantifying changes in gene expression in virus-infected tobacco

Baek, Eseul,Yoon, Ju-Yeon,Palukaitis, Peter 3M Company 2017 Virology Vol.510 No.-

<P>To facilitate quantification of gene expression changes in virus-infected tobacco plants, eight housekeeping genes were evaluated for their stability of expression during infection by one of three systemically-infecting viruses (cucumber mosaic virus, potato virus X, potato virus Y) or a hypersensitive-response-inducing virus (tobacco mosaic virus; TMV) limited to the inoculated leaf. Five reference-gene validation programs were used to establish the order of the most stable genes for the systemically-infecting viruses as ribosomal protein L25 > P-Tubulin > Actin, and the least stable genes Ubiquitin-conjugating enzyme (UCE) < PP2A < GAPDH. For local infection by TMV, the most stable genes were EFl alpha > Cysteine protease > Actin, and the least stable genes were GAPDH < PP2A < UCE. Using two of the most stable and the two least stable validated reference genes, three defense responsive genes were examined to compare their relative changes in gene expression caused by each virus.</P>

감자 이상모자이크증상의 몇 가지 발생원인 및 제초제에 의한 증상 유기

권민(Min Kwon),함영일(Young-Il Hahm),김현준(Hyun-Jun Kim),임명순(Myoung-Soon Yiem) 한국농약과학회 2001 농약과학회지 Vol.5 No.2

In recent, non virus-induced mosaic symptoms(NVMS) on potato leaves were observed in the seed potato fields, and its incidence rate was 5~20% nationwide. It made difficult to rogue out virus-infected plants, and caused much arguments between seed potato production farmers and seed potato inspectors. The objectives of these experiments were to find out the causes of NVMS, and also to induce mosaic symptom(phytotoxicity) on potato plants by treatment of several herbicides. No significant correlations were found between incidence rates of NVMS and values from soil analyses; soil pH, soil EC, organic matter content, and contents of inorganic constituents(P₂O?, NO₃, Ca, Mg, K) in the soil around the potato planted. The examinations by ELISA, virus indicator plants, and TEM showed that NVMS on potato leaves was not caused by the viruses infection. But, the use of herbicides could induced the NVMS on potato leaves. The incidence rates of potato treated with pendimethalinㆍlinuron of 400 ㎖/10 a, pendimethalin of 200 ㎖/10 a, pendimethalinㆍoxadiazon of 300 ㎖/10 a, and control were 61.1%, 47.2%, 19.4%, and 1.4%, respectively. Based on these results, we confirmed that the treatment of pendimethalin alone and in mixture with other herbicides were the reason of NVMS on potato leaves. The yields among test plots were similar except dicamba treated plot, which decreased by about 23% compared to control plot. When their progenies harvested in 1999 were planted in the following season, no symptoms of mosaic were observed.

Potato virus Y (PVY) detection in a single aphid by one‐step RT‐PCR with boiling technique

김주일,차덕재,권민,Rameswor MAHARJAN 한국곤충학회 2016 Entomological Research Vol.46 No.4

Potato virus Y (PVY) (Potyviridae: potyvirus) is a serious emerging virus affecting seed potato worldwide. It affects the seed potato by transmitting non‐persistently via aphids. Sometimes this virus induces symptomless infection and is hard to detect in potato. So, it requires a specific and quick diagnosis for efficient examination. Recently, a reverse‐transcription polymerase chain reaction (RT‐PCR)‐based PVY detection method has been developed from plant as well as insect vectors. However, it is a complex and time consuming method. Here, we developed a simple PVY detection method that uses boiling for releasing the viral RNA from aphid stylets, and amplification by PVY‐specific primers located in the viral coat protein gene. The method is suitable for various strains. This simplified method could save time compared to earlier detection methods because of the simplified RNA extraction step. Following this procedure, we tested this one‐step RT‐PCR‐based PVY detection method by using three PVY vectoring aphid species (Myzus persicae, Aphis gossypii and Macrosiphum euphorbiae) as well as other sucking insects such as thrips, Frankliniella occidentalis. The reliability of a newly developed primer set was suitable for RT‐PCR and procedures were successfully demonstrated for virus detection. This PVY detection method is rapid, easy to use and suitable for large‐scale testing in laboratories of seed potato, and could potentially be applied to virus‐free seed potato production.

Partial Biological and Molecular Characterization of Tomato yellow fruit ring virus Isolates from Potato

Reza Pourrahim,Alireza Golnaraghi,Shirin Farzadfar,Kazusato Ohshima 한국식물병리학회 2012 Plant Pathology Journal Vol.28 No.4

Eight potato-producing provinces of Iran were surveyed during the growing seasons of 2004−2006 to detect the presence of Tomato yellow fruit ring virus (TYFRV),a tentative species in the genus Tospovirus. A total of 1,957 potato leaf samples were collected from plants with tospovirus-like symptoms of chlorotic or necrotic spots, chlorosis and necrosis. The samples were tested by enzyme-linked immunosorbent assay using TYFRVspecific antibodies. Among those tested, 498 samples (25.4%) were found to be infected with the virus. The virus was detected in 72.4% of the potato fields in all provinces surveyed. Thirteen potato isolates of TYFRV were selected for further biological and molecular studies. Based on their reactions on Nicotiana tabacum plants, the isolates were separated into two groups,namely L (local infection) and N (systemic infection). The nucleotide sequences of the nucleoprotein (N) genes of the isolates were determined and compared with the homologous sequences in Genbank. No recombination evidence was found in the isolates using different recombination-detecting programs. In the phylogenetic tree, the potato isolates fell into two major groups: IRN-1 and IRN-2 corresponding to the two biologically separated groups. This study shows for the first time the biological and phylogenetic relationships of geographically distant TYFRV isolates from potatoes in the mid-Eurasian country of Iran.