巨量元素缺乏對玫瑰桉苗木生長及營養狀況之影響

Effect of Macronutrient Deficiency on the Growth and Nutrient Status of Eucalyptus grandis Seedlings

程煒兒(Wei-Er Cheng) ； 洪富文(Fu-Wen Horng)

《林業試驗所研究報告季刊》 6卷2期 (1991/06) Pp. 133-146

https://doi.org/10.7075/BTFRI.199106.0133

摘要

為探討玫瑰桉苗木缺乏巨量元素所呈現之症狀。以及對其生長和營養狀況之影響，供為研判該樹種養分缺乏之依據，並提供施肥參考，經27週培育，其中後15週特以缺乏單一養分之營養液培育苗木，所得結果顯示：1.缺氮植株矮小，葉片初黃化，隨後變淡紅色；缺磷葉片為暗紫藍色，較正常株小；缺鉀葉片黃化，出現壞疽斑，葉尖焦枯，頂端枝條縮短，成圓形灌叢狀；缺鎂自葉基開始黃化，隨後葉片呈淡黃色夾雜淡紅色，葉片早熟而脫落。2.巨量元素缺乏對玫瑰桉苗木生長影響最嚴重者為氮素，其全株乾物重僅為完全營養液培育苗木之2.6%；其次是缺磷11.6%；缺鉀66%；缺鎂73%與缺鈣88%。故氮素與磷素為玫瑰按苗木生長之決定性養分。3.與培育於完全營養液玫瑰桉苗木葉片中各養分濃度間之適宜比例相比較，若養分不均衡，則生長欠佳。4.巨量元素缺乏對玫瑰桉苗木養分吸取有不同程度之影響，而培育於完全營養液苗木所吸取之各養分量，以及各養分元素間之比例(N：P：K：Ca：Mg=5.1：1.2：4.7：3.9：1)，可提供為玫瑰桉苗木栽植於不同生長介質時養分供應之參考。

關鍵字

玫瑰桉 ； 巨量元素缺乏 ； 營養狀況

並列摘要

The aim of the study was to develope a reference for the diagnosis of macronutrient deficiency and for optimum fertilization of Eucalyptus grandis seedlings in nursery or plantations. Eucalyptus grandis seedlings were grown for 27 weeks in silica sand culture, including the final 15-week under single element deficiency nutrient solution, for examining the visual nutrient deficiency symptoms, and the growth and nutrient status of the seedlings.
The results of this study indicated that:-
The N deficient seedlings were small and their leaves were initially yellowish in color and then turned to pink. Seedlings, with phosphorus deficiency were smaller than normal, and leaves turned to dark purplish blue color. Yellow leaf tips was the first sign of potassium deficient seedlings followed by necrotic spots and scorched appearance, branches were shorter than normal at the upper parts gave a bushy round topped appearance. The symptoms of Magnesium deficiency were initially yellowing from the leaf base, then extend to the whole leaf. Following this, leaves turned to light yellowish color with pink spots and falled prematurelly.
The Growth of Eucalyptus grandis seedlings was reduced as resulted from the nutrient deficiency. The total dry weight of N deficient seedling reduced to only 2.6% of those grown in the complete nutrient solution. And, with the deficiency of P, K, Mg and Ca, the total dry weight reduced to 11.6%, 66%, 73 %and 88%, respectively. This indicated that nitrogen and phosphorus would be the crucial nutrients for the growth of Eucalyptus grandis seedlings.
The abnormal growth of nutrient deficient seedlings was partially caused by the imbalance of nutrients, as indicated by the deviation of the nutrient ratio from that in complete nutrient seedlings.

並列關鍵字

Eucalyptus grandis ； Macronutrient deficiency ； Nutrient status