• Mycobiology
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• v.51 no.4
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• pp.195-209
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• 2023

The seed borne disease such as bakanae is difficult to control. Crop yield loss caused by bakanae depending on the regions and varieties grown, ranging from 3.0% to 95.4%. Bakanae is an important disease of rice worldwide and the pathogen was identified as Fusarium fujikuroi Nirenberg (teleomorph: Gibberella fujikuroi Sawada). Currently, four Fusaria (F. fujikuroi, F. proliferatum, F. verticillioides and F. andiyazi) belonging to F. fujikuroi species complex are generally known as the pathogens of bakanae. The infection occurs through both seed and soil-borne transmission. When infection occurs during the heading stage, rice seeds become contaminated. Molecular detection of pathogens of bakanae is important because identification based on morphological and biological characters could lead to incorrect species designation and time-consuming. Seed disinfection has been studied for a long time in Korea for the management of the bakanae disease of rice. As seed disinfectants have been studied to control bakanae, resistance studies to chemicals have been also conducted. Presently biological control and resistant varieties are not widely used. The detection of this pathogen is critical for seed certification and for preventing field infections. In South Korea, bakanae is designated as a regulated pathogen. To provide highly qualified rice seeds to farms, Korea Seed & Variety Service (KSVS) has been producing and distributing certified rice seeds for producing healthy rice in fields. Therefore, the objective of the study is to summarize the recent progress in molecular identification, fungicide resistance, and the management strategy of bakanae.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.65-65
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• 2020

Bakanae disease, caused by Gibberella fujikuroi, is one of the most devastating diseases threatening rice production in Korea. In recent years, the incidence of bakanae disease became alarming due to the mechanical transplanting practice where the spread of bakanae can be amplified during accelerating seeds growth, due to the use of seeding boxes. The development of resistant rice cultivars could be the primary and effective method for controlling bakanae disease. However, the effects of individual resistance genes are relatively small. Therefore, pyramiding of bakane R genes in rice breeding is a promising strategy having a high potential to mitigate the advert effects of bakanae disease. This study employed a gene pyramiding approach to develop bakanae disease resistant rice lines carrying qBK1, qFfR1 introduced from rice line MY299BK and cv. Nampyeong, respectively. The MY299BK carries qBK1 introduced from cv. Shingwang, which was found to have a high resistance compare to Nampyeong. In addition, the pyramiding effect of the qBK1 and qFfR1 resistance genes were investigated, and the presence or absence of these genes helped us investigate their interaction through bioassay method and MAS. Furthermore, the distribution of resistance in the population showed a biased distribution toward resistance in the F6:7 populutions. However, we could not confirm the accumulation effect of the resistance gene, but the difference between the two genes by the SN2 marker was confirmed. Therefore, the qBK1 gene harbored by MY299BK appears to be different from the qFfR1 carried by Nampyeong, suspected to possess a different bakanae disease resistant gene different from those found in MY299BK and Nampyeong.