Effect of Organic and Conventional Crop Rotation, Fertilization, and Crop Protection Practices on Metal Contents in Wheat (Triticum aestivum)

Abstract

The effects of organic versus conventional crop management practices (crop rotation, crop protection, and fertility management strategies) on wheat yields and grain metal (Al, Cd, Cu, Ni, Pb, and Zn) concentrations were investigated in a long-term field trial. The interactions between crop management practices and the season that the crop was grown were investigated using univariate and redundancy analysis approaches. Grain yields were highest where conventional fertility management and crop protection practices were used, but growing wheat after a previous crop of grass/clover was shown to partially compensate for yield reductions due to the use of organic fertility management. All metals except for Pb were significantly affected by crop management practices and the year that the wheat was grown. Grain Cd and Cu levels were higher on average when conventional fertility management practices were used. Al and Cu were higher on average when conventional crop protection practices were used. The results demonstrate that there is potential to manage metal concentrations in the diet by adopting specific crop management practices shown to affect crop uptake of metals.

Metals in organic and conventional wheat flours determined by an optimised and validated ICP‐MS method

“…Analyses for metals in wheat flours are therefore important from both a nutritional and a toxicological point of view. The multi-element contents of wheat grain are the result of many factors such as agricultural practices, genetic factors, soil characteristics, seasonal influences and contamination from anthropogenic sources (Adriano, 2001;Kirchmann et al, 2009;Cooper et al, 2011).…”

Agricultural Methods for Toxicity Alleviation in Metal Contaminated Soils: A Review

“…Accordingly, Kabata-Pendias (2001) reported that after the addition organic matter, Cu, Zn, Pb and Cd could accumulate in organic horizons of soil as stable forms. However, as reported by Cooper et al (2011), regular application of organic matter may reduce plant uptake of metals because addition of organic compounds to the soil could lead in increased chelation of metals reducing plant availability of them.…”

“…According to Harris and Taylor (2001), reduction in Cd accumulation in durum wheat seeds by Zn might be due to alleviation of Zn stress through application of Zn fertilizer. Cooper et al (2011) too have conducted a study with wheat and based on the results, they stressed a potential risk of higher levels of Cd accumulation if P-fertilizers with a higher Cd content are used. In accordance with their view, Thomas et al (2012) reported that heavy metal accumulation in the soil does not depend on levels of phosphate fertilizer but on the levels of heavy metal impurities in the phosphate fertilizer.…”

“…It has been reported that over 80% of the intake of metals such as Cd and Pb could be from crop-based foods (Marzec and SchlegelZawadzka, 2002). However, the accumulation of metals in agricultural crops and thresholds of dietary toxicity in soil-crop system may vary with several factors (Islam et al, 2007;Cooper et al, 2011). In this context, Singh et al (2012) reported that accumulation amount depends on crop species and variety.…”

“…While Tangahu et al (2011) and Islam et al (2007) reported that nature of the soil (soil pH, organic matter content, clay mineral and other soil physical and biochemical properties) and climatic conditions are also important in determining the metal content in crop plants. According to Cooper et al (2011), season and crop management practices too are involved in determining the metal content in crops. As reported by Islam et al (2007), the interactions of soil-plant roots-microbes play important roles in regulating heavy metal movement from soil to the edible parts of the crops.…”