Stripe rust (or yellow rust) caused by Puccinia striiformis f. sp. tritici is the major wheat disease responsible for deteriorating global wheat yield and quality. Although stripe rust appears to be prevalent mainly in temperate areas, new races adapting to high temperature have recently appeared in warmer areas, such as Australia, the Middle East, and Africa, increasing the threat to global food security. Among the approximately 80 reported genes for stripe rust resistance, six (Yr5, Yr7, Yr15, Yr18, Yr36, Yr46) have been cloned. Stripe rust resistance genes are generally classified into race-specific (or all-stage) and non-race-specific (or high temperature adult plant) resistance genes. While resistance conferred by most race-specific genes are overcome by the appearance of new pathogen races within few years, non-race-specific genes, such as Yr18, Yr36, and Yr46, provide more durable resistance and are often stable for several decades. Yr18/Lr34/Sr57/Pm38 and Yr46/Lr67/Sr55/Pm46 are especially useful in breeding as they confer resistance to leaf rust, stem rust, and powdery mildew as well as stripe rust. Unlike the extensive global research efforts, few studies have been conducted in Korea regarding breeding and genetics for stripe rust resistance. To prevent damage by stripe rust in advance, it is important to monitor the changes in major pathogen races in Korea, evaluate major wheat breeding lines and landraces for stripe rust resistance by establishing an efficient screening system, and introduce new germplasm with various resistance genes. Reinforcing wheat molecular genetics and genomics capacity is also important to enable identification of new stripe rust resistance genes and efficient transfer of the novel genes into elite wheat cultivars using molecular markers.

The objective of this study was to identify quantitative trait loci (QTL) of spike length by association analysis with 94 doubled haploid wheat lines derived from Keumkang and Olgeuru. Days to heading date, culm length, spike length, and kernels per spike were evaluated in 2017 and 2018 in upland conditions. Culm length and spike length were biased short culm length and spike length (skewness=0.2 and 1.5, respectively). Kernel number per spike was biased low kernel number per spike (skewness=0.8). A genetic map was constructed with 170 microsatellite marker loci. One QTL was detected for spike length. The QTL on chromosome 4A, qSL-1 was detected by Xwmc283 and Xbarc327 explained 44.3% of the phenotypic variation. The QTL was applied to validate the relationship between genotypes of QTL and 29 Korean wheat cultivars grown for nine years under upland conditions. Korean wheat cultivars were classified into 5 types based on the combination of the two SSR markers. In Korean wheat cultivars, genotype b at Xbarc327, which was homozygous to Keumkang, had a shorter spike length (7.48 cm) than genotype c, which was different from the genotypes of Keumkang and Olgeuru, (8.45 cm). The two Korean wheat cultivars with genotypes ac at Xwmc283 and Xbarc327 had longer spike length (8.45 cm) than genotypes ba and bb (<7.42 cm).

The cultivation of early maturing rice in the Honam plain area of Korea is increasing to diversify the cropping systems. The cropping systems of this rice are usually classified as early, ordinary, and late cultivations based on transplanting time. The characteristics of varieties vary depending on the cultivations. To evaluate the performance of varieties and interpret the relationships between genotype and environment, nine yield and 17 panicle-related traits of six early maturing rice varieties (Jopyeong, Odae, Unkwang, Haedamssal, Jinkwang, and Haedeul) were characterized on early, ordinary, and late cultivations. Heading date was longer in order of early, ordinary, and late cultivations. The cumulative mean temperature of growth stage was similar for all cultivations. The variation in the number of spikelets per panicle (NS) was mainly due to the variety and the traits related with secondary rachis-branch were affected more by variety than the traits related to primary rachis-branch. The varieties with the highest yield were Haedamssal on early maturing cultivation and Unkwang on ordinary and late cultivations. Haedamssal displayed a panicle-number type plant architecture with relatively higher number of panicles per hill (PN) and average NS. Unkwang exhibited panicle-weight type with many NS and less PN. Additive main effects and multiplicative interaction analysis revealed that, NS and HD were mostly affected by genotype and environment, respectively. Among yield-related traits, NS contributed the most to enhanced yield of varieties in all cultivations. NS could be the target trait of breeding programs intended to improve the yield potential of early maturing rice adaptable to the Honam plain area. However, proper PN should be considered because PN, which was negatively correlated with NS, also affected the yield.

An advanced F₈ population was derived from a cross between the hard wheat cultivar “Keumkang” carrying Pinb-D1b and the soft wheat cultivar “Olgeuru” carrying Pinb-D1a. A breeding line named “Hetero”, which exhibited the heterozygous-like Pinb-D1a/Pinb-D1b genotype, was selected by sequence analysis and KASP (Kompetitive Allele Specific PCR) assay. Physicochemical and processing characteristics of flour were tested in the Hetero line and compared with the two parental cultivars for two years. Hetero display a Glu-1 composition similar to Keumkang and a Glu-3 composition intermediate between Keumkang and Olgeuru. Contrary to the expectation that Hetero carrying the Pinb-D1a/Pinb-D1b genotype would exhibit an intermediate phenotype between the two parents, its overall flour physicochemical characteristics were more similar to Keumkang than to Olgeuru. The flour yield of Hetero (71.6%) was lower than that of Keumkang (74.5%). However, the flour particle size (73.3 μm) and damaged starch content (4.6%) of Hetero were similar to those of Keumkang (71.9 μm and 4.5%). The protein content (16.5%) and sodium dodecyl sulfate-sedimentation volume (72.8 mL) of Hetero were higher than those of Keumkang (14.0% and 57.5 mL) and Olgeuru (11.4% and 45.5 mL). The mixograph water absorption (68.7%) and mixing tolerance (17.7 mm) values of Hetero were higher than those of Keumkang (65.6% and 15.9 mm) with the same mixing time of 3.9 min. The bread loaf volume of Hetero was lower than that of Keumkang (866.7 vs. 894.7 mL). The cooked noodles hardness of Hetero was higher than that of Keumkang (5.9 vs. 4.7 N).

Perilla has a long history of cultivation and consumption in Korea. Its cultivar ‘Sodam’, which is used for its oil and powder, was developed from a cross between two parents ‘K015926’ and ‘Miryang27’. The parents were crossed in 2004, and their progenies were selected from F₃ to F₅ generations through pedigree method. Regional yield trials (RYTs) were conducted in four regions from 2012 to 2014. ‘Sodam’ is a light gray and small spherical-seeded cultivar. It matures earlier (October 2) than ‘Saeyeopsildeulkkae’, a standard cultivar, and the number of flower clusters per plant as well as the number of ears per cluster is higher in ‘Sodam’ than in the standard cultivar. Its seeds contain approximately 46.4% crude fat, and the oil is rich (about 65.0%) in alpha-linolenic acid, an omega-3 fatty acid. ‘Sodam’ is characterized by upright plant growth with narrow branch angles. The average yield of this cultivar was 1.23 ton/ha in adaptable regions. ‘Sodam’ is expected to be a potential cultivar source for production of good quality perilla oil (Registration No. 6729).

‘Godangok1’, a sweet corn hybrid obtained by crossing the inbred KSE13 (female) and KSE37 (male), was developed by the maize breeding team at the National Institute of Crop Science (NICS), Rural Development Administration, Korea, in 2016. ‘Godangok1’ has the sugary enhancer (se) gene, and the ear is yellow-white. The number of days to silking of ‘Godangok1’ was 59, similar to ‘Danok3’ (check variety), but ear length and the ratio of kernel set length to ear length (18.7 cm and 96%, respectively) were superior to those of ‘Danok3’. The resistance to Bipolaris maydis, Exserohilum turcicum, and Ostrinia furnacalis was similar to that exhibited by ‘Danok3’, whereas the lodging tolerance was stronger than that of ‘Danok3’. The fresh ear yield of ‘Godangok1’ was 6,530 ears, with 1,139 kg per 10a, and the sugar content was 20.8 °Brix. The hundred kernel weight was 27.4 g, smaller than that of ‘Danok3’. The flavor was excellent and assigned a sensory score of 5.7. Unique properties of ‘Godangok1’ coded by the recessive se gene are eliminated due to crosspollination when growing along with other types of corn such as general corn (sh, sh2, bt, etc.). Therefore, it must be isolated in time or space and harvested in order to produce high-quality sweet corn (Registration No. 7506).

The rice cultivar ‘Misiru’, which is ideal for rice flour production by dry milling, was developed by the rice breeding team at the National Institute of Crop Science (NICS), Rural Development Administration (RDA), Korea, in 2017 to vitalize the rice processing industry. It is derived from a cross between ‘Daeripbyeo1’ and ‘Seolgaeng’. ‘Misiru’ was grown on a middle plain area by ordinary cultivation methods. The heading date was on August 13, culm length was 85 cm, and there were 12 panicles and 112 spikelets per panicle. The ripened grain ratio was lower than that of ‘Hwaseong’; however, the 1,000 brown rice weight was 30.8 g, about 8 g heavier than that of ‘Hwaseong’. ‘Misiru’ showed medium resistance to blast but susceptibility to bacterial blight, viruses, and insect pests. It was resistant to lodging, whereas pre-harvest sprouting rate and cold tolerance were similar to those of ‘Hwaseong’. The milled rice appeared non-glutinous opaque, with opaque grain rate of 83.7%. The rice grain was soft and starch granules in the endosperm were of spherical type, similar to wheat. The grain contained 6.4% protein and 18.6% amylose (the content of the latter was similar to that in ‘Hwaseong’). However, its milled rice recovery rate was lower than that of ‘Hwaseong’. The average size of dry-milling rice flour was 64.4 μm, and the rate of damaged starch was 5.2%, lower than that of ‘Hwaseong’. ‘Misiru’ milled rice yield was 5.66 MT/ha, 8% higher than the yield potential of ‘Hwaseong’. The cultivar ‘Misiru’ is thus suitable for rice flour production by dry milling (Grant No. 7682).

A peanut cultivar ‘Sewon’(Arachis hypogaea ssp. fastigiata L.) was developed at the Department of Southern Area Crop Science, National Institute of Crop Science (NICS) in Milyang, Korea, in 2017. The cultivar is a cross between the Shinpung-type red skin ‘Charmwon’ and the Virginia-type large grain ‘Milyang27’. ‘Sewon’, which is a Shinpung type of plant, had 13 branches per plant, main stem length of 35 cm, and branch length of 51 cm. Each pod contained two grains with red testa and a large and long ellipse-shaped kernel. The cultivar yielded 38 pods per plant, 113 g of 100-seed-weight (dry), and 1.73 seeds per pod in the regional yield trials (RYT). Crude oil accounted for 35.2% and protein 31.7% of the seed. This cultivar was resistant to early leaf spot, and it was more resistant to late leaf spot, stem rot, and lodging when compared with that of the reference cultivar ‘Palkwang’. In the three-year-long regional yield trials, ‘Sewon’ was more productive than the reference cultivar; it yielded 11.97 MT/ha of fresh pod and 5.23 MT/ha of dry grain, corresponding respectively to 21% and 16% increase compared with those of ‘Palkwang’. ‘Sewon’ is a promising high yielding peanut with early maturing and cultural stability (Registration No. 7926).

The Goji berry line CBP06419-243 was selected from the hybrids (F₁) between CBP03310-250 (IT232705) and CBP05399-1. The line used for crossing was tetraploid induced by the colchicine treatment on bud. Preliminary yield tests using this line were performed from 2009 to 2011, and the final selected line was named ‘Cheongyang 18’, which was subsequently registered under the name ‘Whasu’ in 2015. The specific characteristics of this cultivar are summarized as follows: The flowers are distinctly larger, fruit is medium in size, long oblong, and red, and flowering commenced on June 21. Branching by pruning generated less than the reference variety Cheongmyeong. The leaf infection rates by Eriophyes macrodonis Keifer were as high as 7.7%. Anthracnose on fruits in open field was slightly more severe compared with the reference cultivar, but the infection rates in rain shelter greenhouses was similar. The content of betaine and free sugar in dry fruit was higher than that of the reference cultivar. The dry-fruit yield decreased about 13% in open field, but increased 18% in rain shelter greenhouses. The cultivar ‘Whasu’ is suitable for cultivation in rain shelter greenhouses because of self-compatibility and high yield. It is not necessary the companion cultivar (Registration No. 6345).

Bakanae disease is an important fungal disease caused by Gibberella fujikuroi. Incidence of rice bakanae disease creates serious problems in the foremost rice producing countries, affecting more or less all known rice cultivars. Breeding rice cultivars resistant to bakanae disease will thus be a cost-effective alternative to the application of fungicides. ‘MY299BK’ was derived from a cross between YR24982-9-1 and ‘Ilpum’ in 2008. A promising line, YR28297-1-38-1-1, was selected from among the progeny and designated ‘Milyang299’ in 2013. The local adaptability test of ‘Milyang299’ was carried out at five locations from 2014 to 2016 and named ‘MY299BK’. The heading date of ‘MY299BK’ was Aug. 15, typical for a medium-late maturing cultivar. Its culm was 71 cm long, there were 114 spikelets per panicle, and 1,000 grain-weight of brown rice was 23.4 g; these parameters were similar to those of ‘Nampyeong’. ‘MY299BK’ cultivar was resistant to blast and rice stripe virus, but susceptible to bacterial blight and insect pests. Its yield potential was about 566 kg/10 a at ordinary fertilizer level in a three-year-long local adaptability test. ‘MY299BK’ resistance to bakanae is conferred by the qBK1 gene derived from a tong-il type rice ‘Shingwang’ (Registration No. 7651).

A new mung bean cultivar, Vigna radiata (L.) R. Wilczek ‘Samhwang’, was derived from a cross between ‘Samgang’ and ‘KM9901-3B-15-2-4’ obtained in 2006 and developed at the Jeollanamdo Agricultural Research and Extension Services (JARES) in 2014. ‘Samhwang’ has an erect growth habit, lobed leaflets, green hypocotyls, light yellow corolla, and a dull yellow seed surface. Its stem length was 64 cm, 5 cm shorter than that of the control cultivar ‘Owool’. The 1000-seed weight was 53 g, i.e., 4 g heavier than that of ‘Owool’. ‘Samhwang’ exhibited similar field resistance to mung bean mottle virus, cercospora leaf spot, powdery mildew, and lodging when compared with that of the control cultivar. The sprout yield ratio and hard seed rate were the same as those of ‘Owool’. The average seed yield of ‘Samhwang’ was 1.76 ton/ha, which was 14% greater than that of ‘Owool’ (Registration No. 5877).

A strawberry variety ‘Kuemsil’ was derived in 2007 as an artificial cross between ‘Maehyang’, a high fruit firmness variety and ‘Seolhyang’, a high-yielding variety. The lines were selected from 2009 to 2011, and yield trials of ‘08MS-62’, the final selected line, were conducted to evaluate its characteristics in forcing cultures from 2012 to 2015. After farmer field trials in 2016, the line was renamed ‘Kuemsil’. The general characteristics of ‘Kuemsil’ include upright growth habit, elliptical leaves, and strong vigorous growth. The fruit are conical and light red. This variety is suitable for forcing culture because of the early flower bud differentiation (late August), early first harvest (late November), and continuous formation of next flower clusters. The first cluster bore about 22.4 fewer flowers compared with those of the check varieties (‘Maehyang’ and ‘Seolhyang’), which could reduce the labor cost needed for fruit thinning. ‘Kuemsil’ was high in sugar content (11.1 °Bx) and had optimal fruit firmness (21.9 g/mm²), which is comparable to ‘Seolhyang’. The fruit weight was about 24.6 g, higher than that of the check varieties. The marketable yield was 566.9 g, 14% higher than that of ‘Maehyang’ and 13% less than that of ‘Seolhyang’. Unlike ‘Maehyang’, which is harvested in unripe stage, ‘Kuemsil’ fruit should be harvested at 80% coloration to intensify their deep flavor. ‘Kuemsil’ is more susceptible to Phytophthora crown rot compared with the check varieties, which requires complete disinfection of the soil area (or substrate) of the crown rot. ‘Kuemsil’ was registered with the Korea Seed and Variety Service (KSVS) for commercialization in 2018 (Registration No. 7345).

‘Cheongwoo’, a late maturing, high biomass-yielding rice (Oryza sativa L.) cultivar with high feed value and multiple disease and insect resistance, was developed for whole crop silage (WCS) use. It was derived from a cross between a high biomass and multiple disease resistant line ‘Suweon519’ and early flowering, high-yielding Tong-il type cultivar ‘Gaya’, which exhibited a brown planthopper (BPH) broad resistance conferred by Bph3 and BPH26. The cultivar was characterized by growth period from seeding to heading of about 130 days, culm length of 87 cm, panicle length of 29 cm, 12 panicles per hill, 135 spikelets per panicle, and 1,000-grain weight of brown rice of 21.4 g in the central plain region, Suwon. This long-leaved green WCS rice variety was sensitive to cold stress, similar to ‘Nokyang’, but resistant to premature germination, and germinated well under low temperature conditions. Furthermore, ‘Cheongwoo’ exhibited high lodging resistance at the yellowing stage, the optimal period for harvesting in the field. Additionally, ‘Cheongwoo’ was resistant to leaf and neck blast, bacterial blight (races K1, K2, K3, K3a), rice stripe virus, BPH, and small BPH. Its average dry matter yield for three years reached 20.6 MT/ha, 38% higher than that of ‘Nokyang’. The content of crude protein (5.32%) and total digestible nutrients (71.2%) was higher than that in ‘Nokyang’. On the Korean Peninsula, ‘Cheongwoo’ grows well in central and southern plains, and should be optimally harvested between 15 and 30 days after heading to improve its feeding value and digestion rate in livestock (Grant No. 7662).

A new lettuce (Lactuca sativa L.) with elliptic and dark green leaves, ‘Sambokhacheong’, which is tolerant to tipburn with good yield, was developed from a cross between ‘Meokchima’ (dark red leaves) and ‘Yeoreumcheongchima’ (high yield, green leaves). The crossing and selection for advanced lines was conducted by the pedigree method in 2006-2012. The advanced lines were evaluated for yield and adaptability at several locations in Korea (Gangwon-do, Gyeonggi-do, Chungcheongbuk-do, Chungcheongnam-do, Jeollabuk-do, Gyeongnam-do, and Jeju-do) over three years starting from 2015. The evaluations revealed that this lettuce was early- and medium-maturing leaf lettuce, with a shelf-life of four weeks at 4 ℃, longer than that of ‘Yeoreumcheongchima’. ‘Sambokhacheong’ showed no symptoms of tipburn during hot seasons in the southern parts of South Korea compared ‘Yeoreumcheongchima’. The content of bitter sesquiterpene lactones (latucin, latucin+8-deoxylactucin+lactucopicrin) of ‘Sambokhacheong’ at 57.16 (μg/g, dry weight) was higher than that of ‘Yeoreumcheongchima’. Compared with ‘Yeoreumcheongchima’, the marketable yield of ‘Sambokhacheong’ was 2% higher (at 551 g per plant) and showed late bolting at 111 days after sowing in the summer cultivation season. Its leaves are better, crispier, and sweeter than those of ‘Yeoreumcheongchima’. Therefore, we recommend the new cultivar ‘Sambokhacheong’ for cultivation in hot seasons (Registration No. 6915).

‘Jungmo1022’, a japonica rice cultivar, was developed by a cross between ‘Jinbu31’ (IT212616) and ‘Gyodong23’ (IT213764) by the rice breeding team at the National Institute of Crop Science, Korea, in 2000. ‘Jinbu31’ is tolerant to cold, and ‘Gyodong23’ is early maturing with high yield potential. The growth period of ‘Jungmo1022’ in paddy fields was 116 days on the North-middle highland in Korea, shorter than that of ‘Jinbu’. The culm length of ‘Jungmo1022’ was 67 cm, which was 2 cm shorter than that of ‘Jinbu’. There were 91 spikelets per panicle in ‘Jungmo1022’. The elite line was developed by shuttle breeding in a cold screening field at Chuncheon and highland Jinbu sites in order to screen for cold tolerant varieties. Forty-five lines with more than 50% fertility were selected from the F₂ generation in the cold screening field, and the line SR28990-B-2-2-2 was selected by the pedigree breeding method through F₃-F₇ generations cultivated on the North-middle highland in Jinbu. During the yield trial conducted in 2008-2009 yield trial, an early heading, high-yielding, and cold tolerant line ‘Jinbu 48’ was selected for the local adaptability tests conducted from 2010 to 2012. The early maturing and cold-tolerant ‘Jinbu 48’ was superior to ‘Jinbu’ in exhibiting shorter heading delay, reduced culm length, and spikelet fertility under cold temperature. The new line showed a milled rice productivity of 5.69 MT/ha at Jinbu sites under North-middle highland cultivation and was registered as a new cultivar ‘Jungmo1022’ (Registration No. 5563).