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The damage caused by typhoons to rice production has been increasing. To reduce this damage, wind-tolerant rice breeding programs have been conducted at the Yeongdeok substation (YS) of the National Institute of Crop Science (NICS). This study was conducted to examine the effects of these wind-tolerant rice breeding programs. Under the wind-tolerance screening facility (WTSF), the wind-tolerance of 17 rice varieties bred at NICS (usual rice) and 20 rice varieties bred at YS (wind-tolerant rice) were analyzed by evaluating six traits: white spikelet (WS), white panicle (WP), degree of wind damage (DG), ratio of ripened grain (RRG) at control (RRG_C) and treatment (RRG_T), and reduction rate of RRG between control and treatment (RRG_R). Wind-tolerant rice showed more wind-tolerant characteristics than usual rice, such as lower WS, WP, DG, and RRG_R and higher RRG_T and RRG_C. In the principal component analysis, wind-tolerant rice showing a similar direction for RRG_T and RRG_C were located separately from the usual rice. The adaptability tests of wind-tolerant rice were conducted by evaluating eight yield-related traits in the wind-prone areas. Wind-tolerant rice was divided into three clusters by K-means clustering analysis using WP and RRG_T with the WTSF, RRG, and yield in the wind-prone areas. Among the three clusters, YC2 had the strongest wind tolerance performance, followed by YC3 showing moderate wind tolerance, and YC1 the weakest wind tolerance. ‘Sinbo’, a variety belonging to YC2, exhibited the strongest wind tolerance and high yield potential among all varieties. The wind-tolerant rice varieties bred at YS could be used practically to prevent wind damage and utilize breeding materials to enhance the wind tolerance of rice varieties. [ABSTRACT FROM AUTHOR]

Recent advances in high-throughput sequencing technologies have enabled large-scale cost-effective genotypic analyses, and consequently, obtaining reliable phenotypic data has now become a major bottleneck in data-driven plant breeding. In order to construct a phenotype database for commercial rice varieties released by the National Institute of Crop Science, Rural Development Administration, we initiated a systematic phenotype evaluation project, with the aim of investigating the major agronomic traits of Korean rice varieties released during the period between 1979 and 2017. Despite the narrow genetic background, we found that the days to heading (DTH) and culm length (CL) of the 297 Korean rice varieties assessed exhibited wide phenotypic variation under different environments. Under normal planting cultivation in 2018, the DTH ranged from 48 to 104 days in Suwon, 46 to 111 days in Wanju, and 39 to 97 days in Miryang, with CL values ranging from 59 to 134 cm, 55 to 122 cm, and 57 to 106 cm, respectively. During early planting cultivation in 2019, the DTH ranged from 56 to 113 days (Suwon), 58 to 109 days (Wanju), and 58 to 100 days (Miryang), with corresponding CL values ranging from 63 to 119 cm, 55 to 93 cm, and 51 to 115 cm. Despite the difference of one month in planting dates in 2018 and 2019, DTH in the different years and regions showed highly significant positive correlations (r=0.90-0.98), whereas CL showed positive but weaker correlations (r=0.45-0.82). Furthermore, we detected a weak, although significant, correlation between DTH and CL in each environment (r=-0.18-0.35). Analyses of additive main effects and multiplicative interaction (AMMI) were conducted for DTH and CL to identify rice varieties with stable phenotypes under different environments. We anticipate that the findings of this study will provide a useful rice phenotype database to facilitate genotype-phenotype association studies and data-driven rice breeding. [ABSTRACT FROM AUTHOR]

Rice research in Korea during the past 100 years has gone through tremendous changes and improvements as the country underwent a turbulent history of transformation. Full-scale R&D modernization began in the 1970s, when the government focused policy on achieving self-sufficiency in rice in order to establish the foundation for national economic growth. A major landmark was reached by the development of the rice variety “Tongil” and its cultivation technology, which was at the core of the unprecedented Korean “Green Revolution”. Since achieving self-sufficiency in rice, the breeding goal of Korea moved from increasing yield to improving grain quality as more consumers began to seek high quality food products in the 1980s. This change led to the establishment of the high quality rice breeding platform for enhancing the global competitiveness of Korean rice to cope with the opening of domestic rice market in the 2000s. Currently, the major breeding goals in rice are developing premium quality cultivars for table rice and specialized cultivars for boosting processed food industry. To date, the National Institute of Crop Science has released a total of 300 rice cultivars, including 202 table rice and 98 specialized usage cultivars. Diverse technologies have been developed and utilized for breeding new rice cultivars to meet changing needs. In the next 100 years of rice breeding, the convergence of traditional crop improvement technologies and the new breeding technologies utilizing recent advances in biotechnology will play a crucial role in enhancing breeding efficiency. [ABSTRACT FROM AUTHOR]

The ‘Hangaru’ is a rice variety derived from a cross between ‘Seolgaeng’, which is suitable for making rice wine, and ‘Daeripbyeo1’, which has a heavy grain weight (34.8g) and is suitable for deep fried rice, by the rice breeding team at the National Institute of Crop Science, Rural Development Administration, in 2017. The heading date of ‘Hangaru’ was August 18 and was 10 days later than check variety, ‘Hwaseong’, in Suwon. It had a culm length of 79 cm and 102 spikelets per panicle, and showed similar tolerance to ‘Hwaseong’ when exposed to cold stress. ‘Hangaru’ showed medium resistance to blast disease, but susceptibility to bacterial blight, viruses and brown planthoppers. The milled rice of this variety exhibited an opaque and non-glutinous endosperm. The 1,000 grain weight of brown rice was 32.9 g, which was 10.8 g heavier than that of ‘Hwaseong’; the protein content was 7.0% and the amylose content (19.2%) was similar to that of ‘Hwaseong’. The milled rice recovery rate was lower than that of ‘Hwaseong’. However, opaque grain percentage of milled rice was 88.1%. The hardness of the rice grain was soft and the starch granule shape in the endosperm was round, similar to wheat. The average size of rice flour was 71.0 μm and the damaged starch rate was 6.4%. These results showed that this variety could be suitable for dry milling rice flour production. ‘Hangaru’ had a yield of 5.42 MT/ha of milled rice productivity in ordinary cultivation, which was 99% of that of ‘Hwaseong’. ‘Hangaru’ was adaptable to the middle plain area and Mid-west coast of Korea (Registration No. 7270). [ABSTRACT FROM AUTHOR]