‘Jungmo1024’ is a blast resistant early maturing rice cultivar with high temperature tolerance during grain filling stage. ‘Jungmo1024’ was derived from a sodium azide treatment on ‘Suweon472’, a high yielding japonica elite line which was latterly registered as ‘Namil’. Comparison with the agronomical traits of ‘Namil’, ‘Jungmo1024’ was uniquely characterized as the induced gained function due to the reduced culm length, increased tiller number, strong blast resistance and especially high temperature tolerance during grain filling stage. The high temperature tolerance of ‘Jungmo1024’ was supported by two years experiments by comparing the head rice ratio produced in ordinary paddy field and green house condition. The heading date of ‘Jungmo1024’ was July 29 in central plain area, which was 9 days earlier than that of ‘Hwaseong’. The milled rice yield performance of ‘Jungmo1024’ was about 4.98 MT/ha in local adaptability test for three years. ‘Jungmo1024’ had 69 cm in culm length, which was 15 cm shorter than that of ‘Hwaseong’, 20 cm in panicle length, 16 in tiller number, and 22.3g in 1,000 grain-weight of brown rice. ‘Jungmo1024’ exhibited strong rice blast resistance, but do not have any clear resistance gene sources against bacterial blight, viral diseases and insect fests. ‘Jungmo1024’, nevertheless, would be a useful rice cultivar could be used as a donor line for the breeding programs for developing southern plane adaptable early maturing rice cultivars with enhanced rice blast resistance, lodging tolerance, and especially high temperature tolerance during grain filling stage.

The ‘Jungmo1023’ is the japonica rice variety developed from a cross between Yeongdeog34 and F1 of Iksan456 and SR21097-B-B-19-2-2 by the rice breeding team at NICS in 2012. The heading date of ‘Jungmo1023’ is August 3 in middle plain area and it is six days earlier than ‘Hwaseong’. ‘Jungmo1023’ has 80 cm of culm length which is 4 cm shorter than those of ‘Hwaseong’ and 107 spikelet per panicle. The premature heading rate of ‘Jungmo1023’ was 3.3%. It showed resistance to blast, bacterial blight (K1, K2, K3 race) and stripe virus, but susceptibility to K3a race of bacterial blight, dwarf and black streak dwarf viruses and planthoppers. The milled rice of this variety exhibits translucent and medium short grain shape. It has better palatability index of cooked rice (0.24) and lower amylose content (18.0%) than that of ‘Hwaseong’. The characteristics related to grain milling were better than those of ‘Hwaseong’, especially head rice milling recovery ratio and head rice ratio (96.2%). ‘Jungmo1023’ showed 4.56 MT/ha of milled rice productivity at 7 sites in ordinary cultivation. However, ‘Jungmo1023’ showed early cultivation culture adaptability because of 98% of its yield potential (4.99 MT/ha) compared to high yielding early-maturing variety ‘Jopyeong’. ‘Jungmo1023’ could be adaptable to the middle plain, mid-mountainous and north-east coastal area in Korea (Registration No. 5115).

The ‘Cheongun’ is a rice variety derived from a cross between ‘Suweon462’ which has translucent milled rice and medium maturity and ‘Milyang192’ that the elite line has a bacterial blight resistance and mid-late maturing property by the rice breeding team at NICS, RDA in 2012. The heading date of ‘Cheongun’ is August 13 and five days later than check variety, ‘Hwaseong’. It has 87 cm of culm length and 114 spikelets per panicle. It showed weaker cold tolerance than that of ‘Hwaseong’ while exposed to cold stress. ‘Cheongun’ showed resistance to blast disease, K1, K2 and K3 race of bacterial blight and stripe virus, but susceptible to K3a race, other viruses and planthoppers. The milled rice of this variety exhibits translucent, clear non-glutinous endosperm and short grain shape. It has similar protein content (6.7%) and amylose content (19.5%) to that of ‘Hwaseong’. ‘Cheongun’ showed better palatability index of cooked rice than that of ‘Hwaseong’. Its milled rice recovery rate is similar to those of ‘Hwaseong’. However, whole grain rate of milled rice is higher than that of ‘Hwaseong’. ‘Cheongun’ has 4.98 MT/ha of milled rice productivity in ordinary cultivation. ‘Cheongun’ could be adaptable to the middle plain area in Korea (Registration No. 5114).

‘Jungmo1029’, a late-maturing, high biomass and multiple disease resistant rice (Oryza sativa L.) cultivar, was developed for whole crop silage (WCS) use. It was derived from a cross between ‘Gillim collection1’ with high biomass and ‘Junam’ which has some of diseases resistant genes. This elite cultivar had about 127 days growth period from seeding to heading, 105 cm culm length, 11 panicles per hill, 163 spikelets per panicle and 1,000-grain weight of 21.5 g as brown rice. This WCS rice variety was weak to cold stresses similar to ‘Nokyang’ but was tolerant to lodging in the field. In addition, ‘Jungmo1029’ was resistant to leaf and neck blast, bacterial blight except race K3a and rice stripe virus but susceptible to brown planthopper. Its average dry matter yield for three years reached 17.1 MT/ha, 14% higher than that of ‘Nokyang’. This stay green cultivar had good quality for WCS with low acid detergent fiber and high total digestible nutrients similar to ‘Nokyang’. ‘Jungmo1029’ was suitable for cultivation in the central and southern plain area of the South Korean peninsula and required to harvest 15~30 days after heading to improve the digestibility of cattle (Registration No. 5104).

There are farmer’s demands to develop early-maturing cultivar in order to replace Odae variety to mid-northern inland plain and southern mountainous area of Korea. Saeodae was developed by the rice breeding team of Cheolwon Substation, National Institute of Crop Science (NICS), RDA in 2012. This cultivar was derived from the cross between Geuroobyeo and Suweon 472 in 2001 summer season, and selected by a promising line, SR27376-2-2-1-3, was selected and designated as the line of Cheolweon 81 in 2010. The local adaptability test of Cheolweon 81 was carried out at four locations from 2010 to 2012 and it was named as Saeodae. The heading date of Saeodae is July 25 in Cheolwon area, which is 2 days earlier than that of Odae. This variety has 66cm in culm length and 77 spikelets per panicle. Its 1,000 grain-weight of brown rice is 26.5 g, which is similar to that of Odae. Germination rate at low temperature of this variety is about 70%, and viviparous germination is 17.7%. Cold tolerance of this cultivar is still not good, just mediocre. It shows strong lodging resistance. And premature heading, occurrence of wilting during ripening stage, and leaf senescence at maturing are similar to those of Odae. This variety shows resistance to leaf blast disease, but susceptible to bacterial blight, virus disease and insect pest. This variety has translucent and clear milled rice kernel without white core and belly rice. The yield potential of Saeodae was about 5.26 MT/ha at ordinary fertilizer level in local adaptability test for three years. This variety would be adaptable to mid-northern inland plain and southern mountainous area of Korea.