Bioactive Nutrient Fortified Fertilizer: A Novel Hybrid Approach for the Enrichment of Wheat Grains With Zinc

Abstract

Zinc (Zn) is a critical micronutrient that synergizes nutrient use efficiency, and improves plant growth and human health. Low Zn bioavailability in soils affects produce quality and agricultural productivity worldwide ultimately inducing deficiency in humans and animals. Zn deficiency is a leading cause of malnutrition in underdeveloped countries where a widespread population depends upon staple cereals for daily intake of calories. Modern cereal cultivars are inherently low in Zn, eventually, plants need to be enriched with soil application of ZnSO₄, but due to higher fixation losses, it becomes an inefficient source. Rhizosphere microbiome contains Zn-solubilizing bacteria (ZSB) that improve Zn bioavailability, thus increase the root function, Zn uptake, and plant growth. Niha Corp developed a hybrid process of bioactive nutrient fortified fertilizer (BNFF), which has been used to formulate Zabardast Urea (ZU) by coating bioactive Zn (BAZ) and ZSB on urea. Data obtained for 15 wheat varieties from 119 farmer field demonstration plots and eight replicated trials on 42 locations across multi-environment conditions conclude that ZU significantly improved the plant biomass and yield by 12% over non-Zn control and produced grains with 57 μg/g Zn contents, which can meet a major part of the recommended dietary allowance (RDA) of humans. The study recommends that this microbe-mediated hybrid invention (ZU) is a feasible approach to boost Zn bioavailability and Zn use efficiency, with enhanced yield and quality that may contribute to improve human health. To the best of our knowledge, this is the first wide-scale field testing of Zn enrichment in the grains of bread wheat using an innovative BNFF Urea Z technology.

Keywords: Zn solubilizing bacteria; agriculture productivity; bio-fortified nutrient fertilizer; plant-growth; rhizosphere; zinc-biofortification.

FIGURE 1

Effect of ZU application on the productive tillers (A) and spike length (B) of wheat in the field compared with simple urea and Zn treatments. The data are an average of 8 replicated trials (averaged over locations and varieties).

FIGURE 2

Effect of ZU application on the number of grains per spike (A) and 1,000 grain weight (B) of wheat in the field compared with simple urea and Zn treatments. The data are an average of 8 replicated trials (averaged over locations and varieties).

FIGURE 3

Effect of ZU application on total biomass, grain yield, and straw yield of wheat in the field compared with simple urea and Zn treatments. The data are an average of 8 replicated trials (averaged over locations and varieties).

FIGURE 4

Effect of ZU application on harvest index (A) and grain zinc concentration (B) of wheat in the field compared with simple urea and Zn treatments. The data are an average of 8 replicated trials (averaged over locations and varieties).

FIGURE 5

Effect of ZU application on grain Zn concentration of variety TD-1 (A), Faisalabad-2008 (B), and Galaxy (C) at different locations in the field compared with check plots.

FIGURE 6

Grain yield response to grain Zn contents in check plots (A) and with ZU application (B) of different wheat varieties in the field. The data from 8 replicated trials and 111 farmer field demonstration plots have been jointly loaded on the graph to evaluate the response of varieties. The graphs show a positive linear relationship of grain yield and Zn contents in almost all varieties with significantly higher R²-values.

FIGURE 7

Categorical Principal Component (CAT-PCA) analysis of plant traits measured accross different locations in 15 wheat varieties (A) and Principal Component analysis (PCA) showing the joint loading of whole data in a single plot (B); Total variance explained: 89.19%.

FIGURE 8

Principal Component (PCA) analysis showing the response of wheat varieties after different Zn-treatments; Loaded location-wise (A) and treatment-wise (B).