Foehn damage on rice plant is one of the important abiotic stresses in eastern costal area of Korea. To know the relationship between foehn impact and morphological traits of rice, wind tunnel method was used with 106 rice cultivars. Less influencing traits on foehn were short panicle, large panicle number per hill, thin panicle neck, and the flag leaf of narrow, short and thick. Leaf pubescence reduced the impact on foehn. 'Naepungbyeo' belong-ed to foehn tolerant varietal group, while 'Ansanbyeo' belonged to the opposite group. Three levels of root cutting treatment with two rice cultivars were conducted to evaluate the foehn impact using wind tunnel. The severity of wind damages was followed the sigmoidal curve duration of wind tunnel treatment were prolonged. Different responses of root cutting to wind tunnel treatment could be used to evaluate the severity of the foehn impact. 'Naepungbyeo' was one of the less implausible cultivars on foehn. 'Nae-pungbyeo' showed tolerant response to wind under 21% root removing treat-ment (20㎝ root cutting), however 'Ansanbyeo' was wilted under the same treatment. In case of 35 % root removing treatment(10㎝ root cutting), both rice cultivars failed to alive against foehn wind.

A new Japonica rice variety 'Weonhwangbyeo', released in 1999, was developed from the cross Milyang96//Milyang95/Iri390 made at the Yeongdeog Substation of National Yeongnam Agricultural Experiment Station, RDA. The average heading date of Weonhwangbyeo i

This japonica cultivar was developed from a cross between two F₁ hybrids of YR13168 (Milyang 95/Iri390) and YR13198 (Milyang101/Iri390) using anther culture. It has about 104 days of growing duration from seeding to heading and relatively short

Munjangbyeo' is a japonica rice cultivar developed from a cross between Sangsanbyeo and Suweon 397 by Sangju Substation of National Yeongnam Agricultural Experiment Station, RDA in 1999. The cultivar is early matured with heading date of Aug. 2 in ordinar

Nonghobyeo', was derived from a mutant of Milyang 95, by pure line selection method, which was developed from the single cross between Chukei 1016 and Milyang 79, by the rice breeding team of National Yeongnam Agricultural Experiment Station (NYAES) in 19

Sangmibyeo' is a japonica rice cultivar developed from a cross between Sambaegbyeo and Ou 316 by Sangju Substation of National Yeongnam Agricultural Experiment Station, R.D.A. in 1998. The cultivar is early maturing with heading date of August 7 in ordina

Two rice varieties, 'Oochikara' with large grain and 'Hwayeongbyeo' and their progenies (F1 , F2 , B1 and B2 ) were tested to understand gene action of morphological traits of rice grain and their relationships. The evaluated traits were 1,000-grain weight, grain length, width, thickness, length-width ratio and chalkiness of brown rice. Correlation between grain weight and chalkiness was highly significant in the all progenies, and grain length were not associated with width and thickness in an F2 population. Scaling test and jonit scaling test revealed that inheritance of grain traits were fitted to additive-dominance model without epistasis. Additive effects for the traits were much greater than the dominance effects.

Occurrence of Weedy Rice as Affected by Cultural Practices

본 실험은 1992년 일본 동경농업대학 온실에서 질소 추비와 생장억제제 처리가 벼의 생육과 도복형질에 미치는 형태학적 특성과의 관계를 조사함과 동시에 내성 에틸렌 발생에 미치는 영향을 구명하기 위하여 실험을 수행한바 아래와 같은 결과를 얻었다. 1. 식물생장억제제인 Inabenfide는 초장은 감소시켰지만 수량구성요소, 엽록소 함량, CO2 동화량 및 분벽에는 변화가 없었다. 2. Inabenfide를 수잉기에 처리하였을 때 절간 신장을 감소시켰으나, 세 번째와 네 번째의 절간 직경과 줄기의 두께를 증가시켰다. 3. 질소추비는 대체로 초장과 CO2 동화률에는 뚜렷하게 영향을 나타내지 않았다. 4. 에틸렌 발생은 생장억제제에 대하여 많은 변화를 보여 주었으며 Inabenfide를 출수 15일 전에 처리하였을 때 에틸렌 발생은 무처리구보다 낮게 나타났다. 5. 질소 추비량에 따른 에틸렌 발생은 추비량이 많을 때 발생량이 높았으며 질소 추비와 에틸렌발생 사이에는 높은 상관관계가 있는 것으로 나타났다.

본 시험은 식물생장 조절제 Hoe 78784를 처리하여 수도의 도복 방지효과를 조사하고, 식물생장 조절제의 농도와 처리 시기를 각기 달리하였을 때 수도의 영양생장, 형태적 특성 및 수량에 미치는 효과를 구명하기 위하여 실시하였던 바 몇가지 결과를 얻어 보고하는 바이다. Hoe 78784를 수도 신장기에 처리하였을 때 공시된 품종에서 도복 방지효과가 크게 나타났으며, 특히 도복성 품종인 IR21820-154-3-2-3에 있어서는 수량을 크게 증가시켰다. 생장 조절제 Hoe 78784는 초장 및 절간의 신장을 억제시켰고, 특히 형태학적 특징으로서는 Hoe 78784를 처리함으로써 셋째 및 넷째마디 간의 두께와 직경을 증가시켰으며, 또한 줄기속에 유관속의 수도 증가시켜서 도복 방지효과를 나타낸 것으로 사료되며, 영양 생장기관 및 수량구성 요소에 크게 영향을 미치지 못하였다. 처리시기와 농도별로 볼 때 Hoe 78784를 이앙후 30일날 처리하였을 때는 도복 방지효과가 뚜렷하였으며 수장 및 수량구성 요소에 영향을 미쳐 수량을 크게 감소시켰다. 그러나 출수기때 Hoe 78784 처리는 농도에 관계없이 도복 방지효과를 나타내지 않았고, 기타 제형질에도 영향을 미치지 못했다.