Open AccessIron and zinc levels in Vigna unguiculata (L.) Walp under varying phosphorus and fixed nitrogen treatment conditions
Author(s) -
Ayeni Deborah F.,
Ikwebe Joseph,
Onyezili Francis N.
Publication year - 2018
Publication title -
food and energy security
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.253
H-Index - 25
ISSN - 2048-3694
DOI - 10.1002/fes3.141
Subject(s) - micronutrient , phosphorus , zinc , human fertilization , vigna , chemistry , zoology , soil water , nitrogen , fertilizer , selenium , nutrient , phosphate , horticulture , agronomy , biology , ecology , organic chemistry
Using phosphate fertilizer (particularly at high levels) to improve the phosphorus (P) level of soils during the cultivation of legumes and other cereals unfortunately has negative effect on the levels of micronutrients like zinc (Zn) in grains. This study evaluated the influence of P and nitrogen (N) fertilization on iron (Fe) and Zn levels of cowpea grains. Cowpea genotypes B301, TV u 16514, IT 90K‐205‐8, UAM 09‐1046‐6‐1 and TV u 1272 were grown in greenhouse pots containing barren soils (to simulate micronutrient‐deficient soils) in two stages of varied P (0, 20, 40, and 60 kg P ha −1 ) with and without N (i.e. P only and P v N). The effect of these interactions on Fe and Zn levels were measured. Application of P alone showed no significant ( p > 0.05) negative influence on Zn and Fe content of the grains. However, a combination of N and P fertilization reduced Zn content significantly at 60P ( p < 0.05). Further evaluation showed TV u 1272 as highest in terms of Fe and Zn at all P levels. Significant reduction of grain Zn was found at 60P on N and P interaction. No such negative correlation was observed for Fe. TV u 1272 (a high‐yielding genotype) is recommended as a source of high micronutrient.