Maize yellow mosaic virus (MaYMV) is a tentative new Polerovirus, which was recently identified from maize (Zea mays) in China (Chen et al. 2016). MaYMV has also been reported to infect sugarcane (Saccharum spp.) and itch grass (Rottboellia cochinchinensis), and it has been reported in Asia, Africa and South America (Gonçalves et al. 2017; Palanga et al. 2017; Yahaya et al. 2017). In this study, MaYMV was detected in Panicum miliaceum and Sorghum bicolor using Illumina HiSeq2500 system by Theragen Etex Bio Institute (Suwon, Korea) and SG-VIPdb by SeqGenesis (Daejeon, Korea), as described by Lim et al. (2015). Twenty samples of P. miliaceum and sixty three samples of S. bicolor were collected from July to September and from June to October, 2016, respectively, in South Korea. The high-throughput RNA sequencing of the samples mixed into one pool resulted in a single large contig (5606-nt) with nearly complete MaYMV genome coverage. The contig was assembled from a total of 234,537 reads; the maximum, minimum...

Hylocereus undatus is widely produced in the tropics, and was first introduced to Juju Island, South Korea from Vietnam in 1999. In October 2010, 13 symptomless H. undatus were collected at greenhouses in A and B regions of Jeju Island. Viral Particles were observed in all 5 samples from region B alone, by the direct negative staining (Horne and Wildy, 1963) and ultrathin sections staining method (Choi et al., 2005) using transmission electron microscopy (Carl Zeiss, Oberkochen, Germany). Flexuous rod particles were observed in the sap of the fruit samples. The lengths of the particles ranged from 430–520 nm, and the infected H. undatus cells formed inclusion bodies. According to the large-scale oligonucleotide (LSON) chip assay, a method that efficiently identifies viruses in plants (Nam et al., 2014), the infecting virus in H. undatus was Cactus virus X based on spot intensity. Total RNA was extracted from 8 and 5 samples from regions A and B, respectively, using an Easy-Spin Total RNA Kit (iNtRON, Sung...

In 2015 and 2016, 203 samples of adzuki bean (Vigna angularis) exhibiting viral disease-like symptoms, such as mosaic, mottle, yellowing, dwarfing and leaf rolling, were collected from 18 cities/counties in Korea. Total RNA was prepared from a pooled sample using easy-spinTM Total RNA Extraction Kit (iNtRON Biotechnology, Seongnam, Korea) and used for high-throughput paired-end RNA sequencing. Raw data analysis was conducted by Illumina HiSeq 2500 System at the Theragen Etex Bio Institute (Suwon, Korea) and SG-VIPdb at SeqGenesis (Daejeon, Korea), respectively, as previously described (Lim et al. 2015). As expected, 239 and 10 contigs related to Bean common mosaic virus and Cucumber mosaic virus, which have been previously reported in adzuki bean, were obtained from the adzuki bean transcriptome, respectively. However, in addition to this, 143 and 8 contigs were attributed to two soybean viruses, Soybean mosaic virus (SMV) and Soybean yellow mottle mosaic virus (SYMMV), respectively. To confirm the presen...

Rhodotypos scandens (Thunb.) Makino is known to have a seed dispersal that is thick and stony (endocarp + seeds) and has potential as a landscaping tree seed. In several Rosaceae species, seeds are covered with a hard endocarp, making the internal seeds water-impermeable and germination difficult. Here, we analyzed the morphoanatomical traits and germination properties of R. scandens seeds. To identify ideal seed propagation conditions, we immersed R. scandens seeds in sulfuric acid for varying durations and subjected them to phytohormone (gibberellic acid A3 and fluridone) and a cold stratification (CS) (5 °C) treatment after endocarp removal (ER). The R. scandens stony seeds did not increase in mass by ≥25.0%. Following ER, the seed mass increased by ≥50.0% with water absorption when compared to the initial dry mass. Seed surfaces showed damage and cracks through scarification after 1 h of immersion in sulfuric acid, failing to germinate. A combination of ER, phytohormone treatment, and CS improved seed germination compared to ER alone (26.0 ± 5.3%). Overall, R. scandens seeds showed a dispersal with a hard endocarp from the parent plant, and a pre-treatment with ER, phytohormones, and CS was required for effective seed propagation.

This study predicted habitat distribution changes according to the current distribu seedtion 14 and future climate using the MaxEnt model for endangered Abies nephrolepis Maxim., which is vulnerable to 15 climate change and is a least-concerned species. This study aimed to predict the current distribution and future habitat distribution changes of the endangered A. nephrolepis under climate change using the MaxEnt model. The purpose was to predict the future habitat of the declining A. nephrolepis, to identify the necessity of in situ conservation, and to devise appropriate ex situ seed storage methods. The study utilized climate data from 513 GPS coordinates of A. nephrolepis habitats in South Korea to predict the changes in habitat distribution using the MaxEnt model. The seeds used in the seed experiment were collected from Pyeongchang-gun, Gangwon-do, Republic of Korea in 2019. After confirming an initial seed filling, germination tests were performed under constant temperatures of 15, 20, and 25 °C and alternating day/night temperatures of 25/5, 25/10, 25/10, 20/15, 25/15, 30/15, and 35/15 °C. The seed germination conditions were investigated under 10 different temperature settings. For the determination of storage behavior, seeds were dried at a consistent temperature of 15 °C and relative humidity (eRH) levels of 15, 20, 30, 40, and 50%. Subsequently, the seeds were stored for three months at temperatures of −20 °C and 5 °C, and the vitality tests of the seeds were conducted. Based on these experiments, the storage characteristics of seeds were identified. The results indicated that in all SSP scenarios, it is predicted that A. nephrolepis will become extinct in its habitat by the 2090s. Therefore, it has been shown that on-site and ex situ conservation is necessary. As a result of the seed germination characteristics, the highest germination rate (52.5 ± 16.01%) was achieved at a constant temperature of 20 °C, followed by 25 °C (50.0 ± 10.81%) and 25/10 °C (47.5 ± 4.79%). The highest viability was obtained under 20% eRH (64.0 ± 0%) but was not statistically different from that determined immediately after seed collection. The moisture content was approximately 4.33% fresh weight under 15% eRH at 15 °C. A. nephrolepis seeds are classified as orthodox-type seeds, which do not lose viability at 3%–7% moisture content and after drying under 15% eRH conditions at 15 °C. In conclusion, it can be observed that the seeds can be stored long-term at −20 °C. This research was conducted as a basic study to predict the habitat distribution of the endangered species A. nephrolepis and to establish seed conservation methods. According to the results, it is deemed necessary to conduct both domestic and international analyses of the habitat of A. nephrolepis. In addition, the germination and storage characteristics of A. nephrolepis seeds were confirmed, and based on this, effective seed conservation methods were suggested.