The decrease in seed vigor and grain quality during storage has become an increasingly critical issue due to the extended storage periods resulting from declining rice consumption and climate change in Korea. Despite its importance, few studies have investigated rice seed aging in a large number of Korean rice cultivars. In this study, 53 japonica rice cultivars were evaluated for seed germination, vigor, and grain quality-related traits under accelerated-aging conditions. Seed germination rate was evaluated 7 days after imbibition, following accelerated aging treatments at 42℃ and 95% relative humidity for 8, 12, and 16 days. The average germination rates were 72.9% in the control (0 d), 71.7% after 8 days, 59.0% after 12 days, and 5.6% after 16 days of treatment. Grain quality-related traits, including texture and pasting properties, were also evaluated in rice subjected to the accelerated aging treatment. Adhesiveness and stickiness decreased, whereas hardness and toughness increased, as seed aging progressed. Cluster analysis based on germination rates after accelerated aging identified three distinct clusters, with cultivars in Cluster 3 maintaining a high germination rate of 70.6% even after 12 days of aging, showing clear differences from the other clusters. A principal component analysis (PCA) was conducted to investigate the relationship between germination rate and grain quality-related traits. The results showed that the germination rate and hardness tended to be negatively associated across all three clusters. These results suggested that cultivars with higher germination rates tend to maintain a softer cooked rice texture after aging. Our results provide insight into the relationship between seed aging and grain quality, highlighting elite cultivars that maintain both germination ability and grain quality during storage as valuable resources for breeding programs.

In this study, we aimed to develop a method for the rapid and nondestructive prediction of wheat seed viability using Near-Infrared Spectroscopy (NIRS). Thirteen wheat cultivars were used to establish and validate an NIRS calibration model. The seed samples were divided into a calibration set (n=1,360) and a validation set (n=1,000), representing a wide range of germination rates created through the accelerated aging treatment (98±2% relative humidity, 40°C, 0-10 days). Spectral data were collected within the wavelength range of 400-2,500 nm. Among the three regression models tested, the Modified Partial Least Squares (MPLS) model exhibited the best performance for predicting seed viability, achieving the highest coefficient of determination (R²=0.936) and lowest standard error of calibration (SEC=7.514). The results of this study highlight the utility of NIRS-based models for the rapid, nondestructive assessment of seed viability in wheat. Additionally, this is the first study to apply NIRS for the nondestructive evaluation of wheat seed viability, providing a substantial advancement in seed quality assessment.

Rice is a staple crop in South Korea and globally. The era of global boiling, characterized by rising temperatures and abnormal climatic conditions, significantly impacts crop production worldwide. This study examines the effects of high temperatures and rainfall on early maturing rice varieties, focusing on enhancing heat tolerance during the ripening stage and preharvest sprouting resistance. Utilizing ‘Milyang247,’ a progeny line from ‘Nampyeong,’ we developed the intermediate line ‘MY362VP.’ During 2020–2022, regional adaptability tests were conducted at five locations across Korea. Results showed that ‘MY362VP’ had a viviparous germination rate of 1.9% compared to 19.0% in the control variety ‘Jopyeong.’ Furthermore, ‘MY362VP’ maintained a head rice rate of 90.6% under high temperature conditions, outperforming ‘Jopyeong,’ which has a rate of 62.1%. ‘MY362VP’ produced an average yield of 529 kg/10a, comparable to the control’s 518 kg/10a. This study offers valuable insights for breeding climate-resilient early-maturing rice varieties, positioning ‘MY362VP’ as a promising candidate for future cultivation.

‘Nokwoo’, a mid-late maturing, high dry matter yielding rice (Oryza sativa L.) cultivar with a good early growth and low-temperature germinability, was developed for whole crop silage (WCS) use. It was derived from a cross between a leafy tropical japonica ‘LK1A-2-12-1-1’ with high biomass and good germinability in low temperature and new plant type (NPT), ‘IR72225-29-1-1’ which had low tillering trait, large panicle, dark green leaf, thick and sturdy stem and vigorous root system. This cultivar had about 123 days growth period from seeding to heading, 122㎝ culm length, 29㎝ panicle length, 9 panicles per hill, 144 spikelets per panicle and 1,000-grain weight of 24.4 g as brown rice in central plain region, Suwon. This wide and long leafy WCS rice variety was weak to cold stresses similar to ‘Nokyang’ but was a little resistant to lodging in the field, strong to viviparous germination and good to low temperature germination. In addition, ‘Nokwoo’ was resistant to leaf and neck blast but susceptible to bacterial blight, rice stripe virus and brown planthopper. Its average dry matter yield for three years reached 16.5 MT/ha, 14% higher than that of ‘Nokyang’. This cultivar had 5.3% crude protein and 68.8% total digestible nutrients a little low compared to ‘Nokyang’. In Korea peninsular, ‘Nokwoo’ grows well in central and southern plain and is good to harvest between 15 to 30 days after heading to improve its feeding value and digestion rate of livestock (Grant No. 6072).

The influence of seed maturity, stratification, and seed washing method on seed germination were investigated for establishment of seed propagation system in dropwort (Oenanthe stolonifera DC). Seed germination rate was increased as period of the seed ripening increased, especially the seed over 40 days after flowering showed the highest germination rate. The optimum period of cold stratification treatment to promote seed germination was about 8 weeks. The seed treated by a cold wet stratification with sand exhibited higher germination rate compared to the seed treated by a cold wet stratification without sand. The stratified seeds that were stored in the ground having fluctuating temperature were improved up to 19%, while stratification stored under constant temperature(4°C) did not improve germination rate. In addition, 8 weeks of stratification period under fluctuating temperature in the ground was most effective. Sodium hypochlorite, vital oxide, and distilled water were used as chemicals to remove the germination inhibitor of seed coat. Water washing of seed coat after soaking in 0.5% sodium hypochlorite and 0.0005% vital oxide for three minutes and 60 minutes respectively could effectively remove the germination inhibitors in the seed coat.