Abstract
The uptake ratio of supplying $P^{32}$ labelled double superphosphate and the hastening efficiency of the uptake by addition of magnesium sulfate to the fertilizer were studied on the ${\times}Populus $ albaglandulosa planted with 0/1 cutting in 1975. The results are summerized as follows. 1. Average 13% of supplying double superphosphate was absorbed into ${\times}Populus$ albaglandulosa planted on the reddish heavy clay soil in Institute of Forest Genetics. 2. The accumulation of absorbed magnesium was more amount in leaf than in stem. 3. The uptake ratio of supplying double superphosphate was able to increase up to 16%~33% by the addition of magnesium sulfate to the fertilizer. 4. It might be possible to increase the tree growth following the acceleration of photosynthesis due to the increasing amount of magnesium known to be a component of chlorophyll in leaf as well as to hasten the efficiency of uptake of phosphorus by the addition of magnesium to double superphosphate.
1975년(年) ${\times}$ P. albaglandulosa(은수원사시나무) 0/1묘(苗)를 식재(植栽)하고 방사성동위체(放射性同位體) $P^{32}$-표식(標識) 인산질비료(燐酸質肥料)의 흡수율(吸收率)과 유산고토(硫酸苦土)의 첨가(添加) 시용(施用)에 의(依)한 인산질비료(燐酸質肥料)의 흡수이용촉진효과(吸收利用促進効果)를 시시(試試)한바 다음과 같이 간추릴수가 있었다. 1. ${\times}$ P. albaglandulosa(은수원사시나무)는 구내(構內) 적색계(赤色系) 중점토(重粘土)에서 시용인산질비료(施用燐酸質肥料)의 평균(平均) 13%정도만이 흡수이용(吸收利用)하고 있었다. 2. 흡수(吸收)된 고토분(苦土分)은 줄기보다 주(主)로 잎에 많이 축적되었다. 3. 유산고토(硫酸苦土)를 첨가시용(添加施用)하므로써 시용인산(施用燐酸)의 흡수율(吸收率)은 16~33%선(線)까지 증진(增進)시킬수 있었다. 4. 유산고토(硫酸苦土)를 인산질비료(燐酸質肥料)와 병용(倂用)하므로써 인산(燐酸)의 흡수(吸收), 이용율(利用率)을 증진(增進)시킬뿐만이 아니라 엽록소(葉綠素)의 구성성분(構成成分)인 고토분(苦土分)의 엽내(葉內) 축적량증대(蓄積量增大)는 동화량촉진(同化量促進)과 연결(連結)되어 생장량(生長量)의 증대(增大)도 고려(考慮)될수가 있겠다.