Studies on the plant character of high productive paddy in connection with cations (Ca, Mg, K) content in flag leaves and soil conditions

지엽중(止葉中)의 염기함량(鹽基含量)으로본 고위수량(高位收量)벼의 특성(特性)과 토양(土壤) 조건(條件)에 관(關)한 연구(硏究)

  • Oh, Wang Keun (The City College of Seoul and Institute of Agricultural Sciences) ;
  • Hwang, Young Soo (The City College of Seoul and Institute of Agricultural Sciences)
  • 오왕근 (서울시립산업대학 농업기술연구소) ;
  • 황영수 (서울시립산업대학 농업기술연구소)
  • Received : 1975.01.10
  • Published : 1975.03.20

Abstract

In order to gain information on the plant characteristics of high yielding paddy from the point of view of mineral nutrition and to learn more about soil conditions under which high yields are produced a number of soil samples collected from the field experiment carried out in The City College of Seoul were analysed. In addition, a laboratory experiment carried out to support the field experiment was also analysed. Results obtained are as follows: 1. Generally, the higher the yield of paddy, the higher is the potassium content in flag leaves, whereas the reverse is true for the content of Ca and Mg in the leaves. From these facts it can conceivably be said that the high yielding paddy should absorb a large quantity of potassium and a lesser quantity of calcium and magnesium in the reproductive stage. 2. Leaves of paddy which produced yields over 600kg/10a (a comparatively high yield in the experiment) contained 30-35mg/100g of potassium, less than 25me/100g of calcium, and 10me/100g of magnesium which brings the ratio of $K/{\sqrt{Ca+Mg}}$ over 5. 3. Correlation studies indicated a remarkable relationship between the paddy yield and exchangeable potassium in soil samples taken after harvesting. A similar relationship was observed between the yield of paddy and $K/{\sqrt{Cae+Mge}}$ ratio of the soil samples. 4. A regression between yield of padcy (Y) and exchangeable potassium (Ke) or $K/{\sqrt{Ca+Mg}}$ in soil samples taken after harvesting was shown to be; Y=183.95+2135.86Ke $$Y=352.45+3114.454\;K/{\sqrt{Ca+Mg}}$$ 5. The regression between exchangeable potassium (Ke) in soil samples taken after harvesting and the amount of lime (L) and potassium (P) to be applied is; $$Ke=0.1246+0.00007037L+0.004444P+0.000004444L{\cdot}P$$.

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