Premium
Nitrate Accumulation in Table Beets and Spinach as Affected by Nitrogen, Phosphorus, and Potassium Nutrition and Light Intensity 1
Author(s) -
Cantliffe D. J.
Publication year - 1973
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.2134/agronj1973.00021962006500040012x
Subject(s) - spinach , loam , fertilizer , chenopodiaceae , light intensity , spinacia , nitrate , chemistry , phosphorus , nitrogen , agronomy , nutrient , potassium , horticulture , biology , soil water , ecology , biochemistry , physics , optics , chloroplast , organic chemistry , gene
The objective of this research was to determine the effects of varying levels of N, P, and K fertilizer and light intensity on nitrate accumulation in species grown for human consumption. In greenhouse experiments, table beets ( Beta vulgaris L.) and spinach ( Spinacia oleracea L.) were grown in fine sandy loam soil at three levels of N, P, and K fertilizer in a 3 3 factorial design. Plants were grown under two light intensities, 1.08 ✕ 10 4 lux or 3.23 ✕ 10 4 lux. Nitrate, total N, P, and K were determined on freeze dried table beet leaf blades and roots and on spinach leaves. Fertilizer N had the greatest influence on NO 3 accumulation in all three tissues studied. Varying the rate of fertilizer P had no effect on NO 3 accumulation. Plants of both species grown with the highest rate of K and under the lower light intensity accumulated significantly more NO 3 ‐N than other plants receiving less K. Table beet leaf blades contained three times more NO 3 than roots. Lowering the light intensity from 3.23 to 1.08 ✕ 10 4 resulted in a significant increase in NO 3 ‐N in all tissues tested. Total N concentration increased in all tissues with an addition of N fertilizer or by a reduction in light intensity. In spinach, total N was lower in plants receiving K fertilizer. P and K were lower in beet and spinach leaves that received N fertilizer. Light intensity had no influence on P concentration, while all tissues grown at 1.08 ✕ 10 4 lux contained more K than tissue grown at 3.23 ✕ 10 4 lux. Any factor which increased the total N concentration of the tissue resulted in a corresponding increment in the NO 3 concentration.