Effects of zinc fertilization on growth and leaf nutrient content of Celosia argentea L.

Abstract

Zinc is an important micronutrient for both plant and human health, and dietary zinc is insufficient in many areas of the world, caused by a diet dominated by grains and vegetables grown on zinc deficient soils. Celosia argentea L. is an herbaceous annual adapted to difficult soil conditions, low soil nutrient content, and hot weather and is commonly grown as a leafy vegetable in many parts of Africa. This study was conducted to evaluate zinc fertilization of celosia at levels higher than normally recommended, but below toxic levels, to determine the effect on plant performance and dietary value. Celosia was grown in a controlled environment with four zinc fertilizer treatments (0, 50, 100 and 150 mg Zn·kg-1). Zinc fertilization had minor effects on plant growth, with differences only found in plant height and root fresh weight with both decreasing at fertilization levels above 100 mg Zn·kg-1. Higher zinc fertilization increased root nitrogen, leaf and root zinc, potassium and magnesium concentrations, though leaf magnesium decreased at the highest zinc fertilizer levels. At 50 mg Zn·kg-1, zinc fertilization toxicity symptoms were unexpessed thus it can improve plant performance and provide potentially significant dietary benefits to people with limited access to zinc in their diet.