水耕法によるりんご樹の養分吸収に関する研究(第3報) : 落葉期における N, P, K, Ca 及び Mg の吸収

概要

論文の詳細を見る
1) Continuing to the previous reports on the water culture studies of apple tree, experiments were carried out on the absorption of nitrogen, phosphorus, potassium, calcium and magnesium determined during the leaf fall period from Novem-ber to April of the years 1951_??_1957. Apple varieties used were American Summer Pearmain, Jonathan and Ralls Janett, and these trees were two-year old in the first year and become older by years. 2) Although the absorption of nitrogen and phos-phofus was limited to very little quantity in se-vere winter, before and after of which their absorbed quantity was relatively high. As for potassium, its appreciable amount was discharged by the roots from the later November to the end of the March. 3) The absorbed amount of nitrogen and phos-phorus per unit weight during the leaf fall period decreased as the tree ages increase, especially with phosphorus. The potassium and calcium absorption in this period was minus in each year, but magnesium absorbed very slightly. 4) The rate of nitrogen absorption in the leaf fall period (five months) to annual absorption was about five per cent and slightly higher rate was observed an phosphorus (5_??_8 per cent).
園芸学会の論文