Abstract
The investigate the varietal differences is physiological characteristics related to nutrient uptake and response to nitrogen and phosphorus, a pot experiment was conducted in a temperature control chamber. Three varieties with different cold resistances were grown under normal ($23^{\circ}-25^{\circ}C$) and cold ($15^{\circ}C$) conditions with three nitrogen and phosphorus application levels. The cold temperature was treated for twelve days after thirty days from seeding. The results were summarized as follows: 1. Dry weight and nutrient contents were reduced in cold temperature treatment compared with control and the reduced ratio by low temperature were in order of dry weight 29.4% $P_2O_5$ 21.3%, N 15.3%, $K_2O$ 10.1%, $SiO_2$ 8.7%. 2. The reduced ratio of phosphorus contents of each varieties to normal condition were 13.5% in resistant, 19.5% in medium, 31.1% in susceptible variety, respectively. 3. The phosphorus and silicate contents of plants showed a good relationship with varietal differences in cold resistance but nitrogen and potassium didn't showed, therefore, phosphorus and silicate contents might be used as the index for physiological characteristics related with cold resistance. 4. Phosphorus content slightly increased with nitrogen application but silicate content decreased. Upon phosphorus application, nitrogen and silicate contents were increased.
시비수준(施肥水準)을 달리하여 저온처리를 하였을 때 내냉성(耐冷性)이 다른 수도품종간(水稻品種間) 당양특성(堂養特性)이 어떻게 변화되는지를 알고자 질소(窒素)와 인산(燐酸)의 수준(水準)을 달리하여 재배(栽培) 한30일묘(日苗)를 상온(常溫)(대조구)와 저온(低溫)($15^{\circ}C$ 생육상(生育床))에서 각각(各各) 12일간(日間) 생육(生育)시킨 후 건물중(乾物重)과 식물체중(植物體中) 무기성분(無機成分) 함량(含量)을 조사(調査)한 결과(結果) 다음과 같다. 1. 저온구 수도체는 대조구에 비(比)하여 평균, 건물중(乾物重) 29.4%, 인산(燐酸) 21.3%, 질소(窒素) 15.3%, 가리(加里) 10.1% 규산함량(珪酸含量) 8.70%로 감소(減少)하였다. 2. 대조구에 비(比)하여 저온처리에 의한 인산함량(燐酸含量) 감소율(減少率)은 수도품종(水稻品種)의 내냉성(耐冷性) 강중약(强中弱) 순(順)으로 13.5%, 19.5%, 31.1%이었고 질소(窒素)는 13.5%~16.0%, 가리(加里)는 6.9%~12.9%, 규산함량(珪酸含量)은 5.1%~12.8% 범위(範圍)에서 감소(減少)되었다. 3. 저온처리한 수도체의 인산(燐酸)과 규산함량(珪酸含量)은 내냉성(耐冷性)을 달리하는 품종간(品種間) 차이(差異)를 보이므로써 저온저항성(低溫抵抗性)의 판단(判斷) 지표(指標)로 볼 수 있었다. 4. 질소증시에 따라 저온수도체의 규산함량(珪酸含量)은 약간 증가하고 규산함량(珪酸含量)은 크게 떨어졌으며 인산(燐酸)의 증시로는 질소(窒素) 및 규산함량(珪酸含量)이 다같이 증가되었다.