‘청아’는 중부지역 적응 중생 고품질 벼를 육성할 목적으로 1994년 하계에 외관 품위와 밥맛이 우수한 일본 도입품종인 기누히까리를 모본으로, 농가포장에서 수집된 유전자원 중 숙색 등 외관과 밥맛이 좋은 ‘양주선발’을 부본으로 인공교배한 후, 1995년 하계에 F1 15개체 양성, 1996년 하계에 F2 세대에서 집단선발 하였고 F3∼F5 세대를 집단육종법으로 양성한 뒤 F6 부터 계통육종법에 따라 우량계통을 선발 고정시켰다. 2002년부터 2003년까지 2년간 생산력검정 시험을 실시하였고 품위가 양호하며 밥맛이 좋은 SR21159-B-B-B-26-1을 선발하여 ‘수원495호’로 계통명을 부여한 후 2004년부터 2006년까지 3년 간 지역적응시험을 실시한 결과 그 우수성이 인정되어 2006년 12월 직무육성 신품종 선정위원회에서 국가목록등재품종으로 선정됨과 동시에 ‘청아’로 명명하였다. ‘청아’의 평균 출수기는 보통기 보비재배에서 8월 6일로 ‘화성벼’보다 4일 빠른 중생종이고, 간장 87 cm, 이삭길이 20 cm, 주당 수수 14개, 수당립수 106개, 등숙률 89.1%로 ‘화성벼’와 비슷한 특성이며, 현미천립중이 20.6 g으로 중립종이다. ‘청아’는 잎도열병, 흰잎마름병(K1, K2, K3), 바이러스병 및 멸구류 등 병해충에 대한 저항성은 약하다. ‘청아’의 내냉성은 중강 정도였으며, 불시 출수는 ‘화성벼’보다 약한 경향으로 나타났다. 쌀 품질 특성에서 ‘청아’는 쌀 외관은 심복백이 거의 없이 외관품위가 우수하며, 이화학적 특성 중 아밀로스함량은 19.3%로 ‘화성벼’ 보다 낮은 편이다. ‘청아’의 쌀 수량성은 지역적응시험 보통기 보비재배에서 평균 쌀 수량이 5.56 MT/ha로 ‘화성벼’보다 5% 증수되었다. ‘청아’의 재배적지는 중부평야, 남부중간지 및 중서부해안 지대이다.

‘큰눈’은 다양한 전분 신소재를 육성할 목적으로 1991년 하계에 양질다수성 품종인 ‘일품벼’에 돌연변이처리(MNU)하여 중만생이며 배가 일반벼보다 큰 거대배아미인 ‘Ilpum MNU)36-2-GH1-2-10-1-2-3-2-1’ 계통을 선발하여 ‘수원492호’로 계통명을 부여하여, 2003년부터 2005년까지 3년간 지역적응시험 실시결과 그 우수성이 인정되어 2005년 12월 직무육성 신품종 선정위원회에서 국가목록등재 품종으로 선정됨과 동시에 ‘큰눈’으로 명명하였다. ‘큰눈’의 중부평야지의 평균 출수기는 8월 17일로 ‘화성벼’보다 6일 느리고, 남부평야지 평균 출수기는 8월 15일로 ‘남평벼’보다 1일 빠른 중생종이다. ‘큰눈’의 간장은 86 cm이며, 이삭길이는 23 cm로 ‘화성벼’와 비슷하고, 포기당 이삭수는 ‘화성벼’보다 적으나, 수당립수는 많고, 등숙비율은 낮은 편이며, 현미 천립중은 가벼운 편이다. ‘큰눈’은 도열병 저항성은 약한 반응을 보였으며, 흰잎마름병 및 바이러스병과 벼멸구 및 애멸구 저항성은 없었다. ‘큰눈’은 내냉성검정에서 ‘화성벼’에 비해 출수지연일수가 다소 길고, 냉수구 임실율이 낮아서 내냉성은 약한 편이며, 도복특성검정에서 좌절중은 낮고, 도복지수는 높은 편이나 포장 도복은 강한 편이다. ‘큰눈’은 현미장폭비가 1.62인 중단원립이고, 투명도가 다소 불량하고 심복백이 많아 외관 품위가 떨어지고, 아밀로스와 단백질 함량은 각각 17.5, 5.9%로 ‘화성벼’보다 낮은 편이며, 단당류 및 올리고당 함량은 ‘화성벼’보다 1.4배, 발아현미의 GABA 함량은 발아 2일에서 ‘일품벼’보다 2.8배 많았다. ‘큰눈’의 쌀수량은 보통기재배에서 평균 쌀수량이 4.52 MT/ha로 ‘화성벼’ 대비 89% 수준이었다. ‘큰눈’의 재배적지는 중부평야 및 남부평야지이다.

‘oamibyeo’ a mid-late maturing ecotype with high amylose content in kernels, was developed by the rice breeding team of National Yeongnam Agricultural Experiment Station(NYAES) in 2000 and released in 2001. This variety was derived from the three way cross of Milyang 95//Kimcheonaengmi/2*Ilpumbyeo (in 1992 summer) through the pedigree breeding method and designated as ‘ilyang 168’in 1997. The heading date of ‘oamibyeo’was Aug. 18 in ordinary season with culm length of 85 cm. However, ‘oamibyeo’showed susceptible to bacterial leaf blight, stripe virus and leaf blast disease. The amylose content of ‘oamibyeo’in milled rice kernels is about 26.7% with translucent and clear in chalkness. Thus, ‘oamibyeo’is expected to be used as a source grain for rice noodle industries. The milled rice yield potential of ‘oamibyeo’is about 5.38 MT/ha in local adaptability test of three years and it would be adaptable to Yeongnam plain of Korea.

Brown planthopper (BPH) is a major insect pest of tropical indica and temperate japonica rice in Asia and Africa. A major BPH resistance gene, Bph18 derived from IR65482-7-216-1-2 has been fine mapped on chromosome 12 and confers strong resistance to the Korean biotype of BPH. The Bph18 gene is tightly linked to the STS marker, 7312.T4A and is non-allelic to previously reported resistance genes present on chromosome 12. The Bph18 gene has been transferred into two elite japonica cultivars (Jinbubyeo and Junambyeo) background through marker-assisted backcross breeding (MAB) strategy. Foreground selection using STS markrs linked to the Bph18 gene in advanced backcross progenies confirmed homozygous marker alleles associated with BPH resistance. Background selection of the breeding lines with 260 simple repeat (SSR) markers revealed rapid conversion toward recurrent parent genotypes with less donor chromosomal segments (5.3-16.7%). Major agronomic traits of the progenies were analyzed and some breeding lines have agronomic traits comparable to the recurrent parent. One breeding line (S.523) with multiple-resistance to BPH and major diseases, desirable agronomic traits and grain quality has been recommended for regional testing in Korea. MAB is the suitable strategy to incorporate new genes into susceptible japonica to develop elite breeding lines.

This experiment was carried out to evaluate the agronomic stability of North Korean rice varieties using the statistical model developed by Grafius, Finlay, and Ever hart. The lowest yearly variation based on coefficients of variation was found in Hannam 29 for number of panicles per hill, in Sijoong 9 for number of grains per panicle, in Pyeongyang 3 for ripened grain ratio, in Sijoong 16 for 1,000 grain weight, and in Yeomju 1 for grain yield. By Grafius's model, Pyeongbook 3, Weonsan 66 in early maturing groups and Seohaechalbyeo in medium maturing groups show stable for 3 years. Weonsan 66 in early maturing groups and Seohaechalbyeo in medium maturing groups were found to be highly stable as analyzed by both Finlay and Wilkinson's model and Everhart & Russell's model. With reference to three models, Weonsan 66 was highly stable for 3 years with showing more yield than Odaebyeo in early maturing groups while Seohaechalbyeo was highly stable for 3 years with showing high yield than Hwaseongbyeo in medium maturing groups above 5~;t~;ha-1 of milled rice respectively.

Lodging is classified as root lodging caused by the loss of supporting force in the root, bending caused by the deformation of the stem and breaking where the stem breaks down as loads exceeding critical elasticity were applied. This research excluded breaking which is not in a state of equilibrium and tried to partition the level of lodging using an algebraic model in root lodging and stem lodging, or bending. When a vertical load was applied, the deformation of the stem of rice plant showed the form of a quadratic equation. The trace of the panicle neck in the process of lodging was an ellipse-shape. When loading was pure root lodging, the trace of the panicle neck became a circle of which culm length is the radius. When it was a pure stem lodging, the trace of the panicle neck is an ellipse of which major axis is culm length and minor axis is 0.64* culm length. When both stem lodging and root lodging occurred in a natural setting, the partitioning of lodging can be calculated by a formula using eccentricity of an ellipse, S=e*100/0.768(S is the ratio of stem lodging in the whole lodging, e is eccentricity of the ellipse). This method is expected to be useful in simple lodging partitioning. We could also calculate the partitioning of stem lodging and root lodging as units of angles as an accuracy method, by using a straight line calculated by differentiating a quadratic equation of stem deformation at the origin of the coordinates. These two methods for dividing root and stem lodging showed different values. However, each of them showed almost same values with different lodging degree in one plant.

Low temperature is one of the most severe abiotic stress factors limiting growth, productivity and distribution of winter cereals. Reliable field screening method, which can detect small differences in winter survival, is important for the effective selection and development of plants to identity superior cold tolerant winter cereal genotypes. This study was undertaken to provide improved screening method of winter hardiness in the field by increasing the accuracy in evaluating winter hardiness of barley (Hordeum vulgare L.). We introduced furrow in field screening of winter survival. By sowing the plants at the ridge and base, we could minimize the effect of topographic variation in a field by giving higher and lower level of stress at the same time. This method could be used by breeders to conduct accurate evaluation of winter hardiness by selecting the better treatment, which shows close to normal distribution, among the winter survival rate from the ridge, base and mean survival rate of the two in a screening field.