Effects of foliar fungicide on yield, micronutrients, and cadmium in grains from historical and modern hard winter wheat genotypes

Abstract

Plant breeding and disease management practices have increased the grain yield of hard winter wheat (Triticum aestivum L.) adapted to the Great Plains of the United States during the last century. However, the effect of genetic gains for seed yield and the application of fungicide on the micronutrient and cadmium (Cd) concentration in wheat grains is still unclear. The objectives of this study were to evaluate the effects of fungicide application on the productivity and nutritional quality of wheat cultivars representing 80 years of plant breeding efforts. Field experiments were conducted over two crop years (2017 and 2018) with eighteen hard winter wheat genotypes released between 1933 and 2013 in the presence or absence of fungicide application. For each growing season, the treatments were arranged in a split-plot design with the fungicide levels (treated and untreated) as the whole plot treatments and the genotypes as split-plot treatments in triplicate. The effects on seed yield, grain protein concentration (GPC), micronutrients, phytic acid, and Cd in grains were measured. While the yield of wheat was found to increase at annualized rates of 26.5 and 13.0 kg ha-1 yr-1 in the presence and absence of fungicide (P < 0.001), respectively, GPC (-190 and -180 mg kg-1 yr-1, P < 0.001), Fe (-35.0 and -44.0 μg kg-1 yr-1, P < 0.05), and Zn (-68.0 and -57.0 μg kg-1 yr-1, P < 0.01) significantly decreased during the period studied. In contrast to the other mineral elements, grain Cd significantly increased over time (0.4 μg kg-1 yr-1, P < 0.01) in the absence of fungicide. The results from this study are of great concern, as many mineral elements essential for human nutrition have decreased over time while the toxic heavy metal, Cd, has increased, indicating modern wheats are becoming a better vector of dietary Cd.

Interaction between the Accumulation of Cadmium and Deoxynivalenol Mycotoxin Produced by Fusarium graminearum in Durum Wheat Grains

“…The concentrations of Cu, Fe, Ni, Mn, Zn, Ca, and K measured in grains in the base zone (Table ) were in line with or slightly higher than those commonly reported for wheat grains. , The concentrations of Cu, Mn, Ni, Ca, and K decreased ( p < 0.05) with increased soil Cd content, on average by respectively, 35, 54, 44, 13, and 18%, between Cd0.1 and Cd10, whereas the concentrations of Fe and Zn were not affected ( p > 0.05) by the Cd treatment. As observed for Cd (see above), the concentrations of Mn, Zn, and Ca in the grains in the base zone were higher ( p < 0.05) in Fusarium-infected than in mock-inoculated plants, by an average of 56% for Mn, 51% for Zn, and 13% for Ca, while the concentrations of the four other elements were not affected ( p > 0.05) by Fusarium infection.…”

“…In cereal grains, micronutrients (e.g., Fe and Zn) and toxic trace metals such as Cd and Pb are preferentially stored in the peripheral aleuronic layer rather than in the starchy endosperm. − Consequently, their concentration in the grain usually decreases with an increase in grain size, which is mainly due to the increase in endosperm. This is one reason for the “dilution effect” described for micronutrients in wheat grains . The relationship between the sink strength for photoassimilates and the concentration of Cd in grains relies on potential decoupling between the allocation of Cd and photoassimilates to the grain.…”

Impact of Foliar Applications of Different Fungicides on Wheat Stripe Rust Epidemics and Grain Yield

“…Nevertheless, the use of fungicides is expensive which a problem is for poor farmers (Ali et al, 2021). Recent studies indicated that the impact of foliar rusts on wheat quality and plant development depends on the level of genotype resistance, yield potential and onset of disease (Herrera-Foessel et al, 2006;Cruppe et al, 2021;Motta-Romero et al, 2021). Ash and Brown (1990) exhibited that an early outbreak of disease percentage had a larger effect on grain yield as compared to the late epidemics.…”

Breeding Bread-Making Wheat Varieties for Organic Farming Systems: The Need to Target Productivity, Robustness, Resource Use Efficiency and Grain Quality Traits

“…Higher concentrations of the toxic metal Cd in conventional wheat grain were linked to higher inputs of mineral P fertilizers (which contain Cd) [ 111 ], but recent variety trials with spring and wheat also identified significant main effects of variety [ 57 , 112 ] (see Table 7 for an example).…”