Rae-Dong Jeong

One-step multiplex reverse transcription-polymerase chain reaction for the simultaneous detection of three rice viruses.

Rice stripe virus (RSV), Rice black-streaked dwarf virus (RBSDV), and Rice dwarf virus (RDV) are major rice-infecting viruses in Korea that can cause serious crop losses. A one-step multiplex reverse transcription-polymerase chain reaction (mRT-PCR) was developed for the simultaneous detection of these rice viruses. Three sets of specific primers targeted to the capsid protein coding genes of RSV, RBSDV, and RDV were used to amplify fragments that were 703 bp, 485 bp, and 252 bp, respectively. The one-step mRT-PCR assay proved to be a sensitive and rapid method for detecting the three rice viruses. This method could be used to facilitate better control of rice viruses.

Applications of ionizing radiation for the control of postharvest diseases in fresh produce: recent advances

Postharvest diseases cause considerable losses to harvested fruits and vegetables worldwide. In addition to various treatments to control postharvest losses caused by pathogens, the global trend is shifting toward more eco-friendly alternatives safer to human health. Thus far, a significant approach to postharvest disease control has mainly relied on the use of synthetic chemicals. However, the intense use of chemical fungicides has caused side-effects such as environmental issues and evolution of resistant isolates. With increasing demand for the use of non-chemicals, ionizing radiation has been investigated for application in many aspects of the postharvest treatment, especially as an approach with significant potential for the control of postharvest disease. Recently, a number of more or less technologically advanced methodologies, i.e., irradiation combined with other types of treatments and induced resistance, have been developed to control postharvest diseases as well as to increase the quality and storage life of fresh commodities. Challenges for future application of irradiation in fresh produce are the cost, lack of irradiation facilities, lack of knowledge about optimal conditions for different commodities, and lack of acceptance of irradiated fresh produce. This review aims to document the advances in our understanding of the effects of irradiation on postharvest disease, the possible modes of action, and the perspectives in commercial use. n nThis article is protected by copyright. All rights reserved.

A nationwide survey and genetic analysis of rice stripe virus in South Korea during 2012–2013

Rice stripe virus (RSV) is a major rice-infecting virus in Korea that has caused a severe resurgence in the western provinces in 2007–2008. The outbreak of RSV in rice was caused by the small brown planthopper Laodelphax striatellus (an RSV vector), which overwinters in temperate climates. Mass immigration of its insect vector from China has been proposed as a critical risk factor in development of the disease. A nationwide survey was done in June and July 2012–2013 in 30 Korean provinces to confirm RSV sequence variation. The sequence of the nucleocapsid protein (NCP) gene and the intergenic region (IR) of RSV RNA3 was analyzed. A phylogenetic analysis of the NCP gene and the IR demonstrated that the 33 isolates were closely related to earlier reported isolates from Japan and China, but the secondary IR structure showed strong geographic clustering. This is the first report on a nationwide RSV survey of Korea. The results will provide information on the relationships among RSV isolates to understand the epidemiology of this rice disease and the effect of climate changes and insect migration.