Perennial forages influence mineral and protein concentrations in annual wheat cropping systems

Abstract

Agricultural land management may influence crop nutritional quality. However, few studies have explored potential connections between crop quality with different land management strategies. We analyzed mineral and crude protein concentrations in spring wheat grain (Triticum aestivum L.) samples from a study in Mandan, ND conducted from 2006 to 2014. The study introduced a perennial forage phase into an annual spring wheat cropping system, in three to four replicates, and previously found yield benefits and enhanced soil parameters in the perennial forage treatments. We determined whether integrating a perennial forage phase into continuous wheat would also affect crop nutritional quality by measuring wheat grain mineral and protein concentrations. Crude protein concentration was greater (p < .05) when wheat followed alfalfa (Medicago sativa L.) and increased linearly after 2–5 yr of established alfalfa. We observed comparable wheat grain crude protein and mineral concentrations between continuous annually fertilized wheat and unfertilized wheat following perennial forages. Negative correlations (p < .001) were observed between wheat grain yield and crude protein, potassium (K), magnesium (Mg), nickel (Ni), phosphorus (P), sulfur (S), and zinc (Zn) concentrations. Discriminate multivariate analyses showed, with 96% predictive accuracy, that differences in crude protein and mineral concentration were largely driven by year of wheat harvest. Differences between harvest years were likely due to timely precipitation at critical Growth Stage 3, during spikelet development. Study outcomes highlighted the important role of perennial forages and environmental factors to influence protein and mineral concentration in spring wheat grain.

Ecological Intensification of Food Production by Integrating Forages

“…Soil stability was enhanced, and surface sediment run-off was shown to decrease when alfalfa was included in the cropping system [159]. Alfalfa can also benefit crop quality as unfertilized spring wheat following alfalfa had greater crude protein than fertilized spring wheat in one study [120].…”

“…There is little published on how the addition of perennials can affect subsequent crop quality. Clemensen et al [120] reported comparable spring wheat protein and mineral concentrations between unfertilized spring wheat grown after perennial forages and fertilized spring wheat. Their data also suggested that incorporating alfalfa into the crop rotation could enhance spring wheat protein but may lower zinc concentration.…”

“…However, there is a need to develop best management practices for integrating perennial forages into cropping rotations across agroecosystems. For example, there has been research on the impacts of different perennial forages and forage mixtures on crop yields [97], soil quality parameters [111], and crop quality [120], but a more extensive evaluation that incorporates different forage species and species mixtures across environmental gradients is needed. There have been studies on the best tillage management system to convert from perennials to annual [166] and the impact of annual crops on subsequent perennial establishment and yield [167], but more in-depth evaluations are needed to achieve a mechanistic understanding of these critical management decisions and the economic benefits associated with these systems.…”

Rotating perennial forages into annual wheat cropping systems: Correlations between plant available soil and grain mineral concentrations

“…Increasing wheat yield with decreasing mineral concentration has been described as a dilution effect (Calderini et al, 1995;Jarrell & Beverly, 1981;McDonald et al, 2008;Slafer et al, 1990), yet it is not well understood. Land management may influence both soil and crop quality (Bauer & Black, 1981;Clemensen et al, 2021;Greenwood et al, 1997;Karlen et al, 1994;Liebig et al, 2018;Shiwakoti, Zheljazkov, Gollany, Kleber, Xing, & Astatkie, 2019;Shiwakoti et al, 2020;Stewart et al, 2016;Wardle et al, 1999;Wedin & Tilman, 1990). However, research associating soil and crop quality parameters is limited.…”

“…Integrating perennial forages into a semi-arid dryland wheat system in the northern Great Plains influenced both soil and crop quality parameters (Clemensen et al, 2021). Liebig et al (2018) demonstrated that incorporating perennial forages into a crop rotation reduced soil acidification and bulk density, and increased particulate organic matter and water stable aggregates in near-surface soil compared with continuous annual wheat.…”