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

Correlations between plant available soil and grain mineral concentrations are often assumed, yet few studies examine these associations. Here, soil and wheat grain samples were analyzed from a semi-arid dryland cropping study in the northern Great Plains conducted between 2006 and 2011. Continuous spring wheat (fertilized) (Triticum aestivum L; CSW) was compared with wheat following 5 yr of perennial forages of either alfalfa (Medicago sativa L.), intermediate wheatgrass (fertilized) (Thinopyrum intermedium (Host) Barkw. & D.R. Dewey sbsp. Intermedium; IWG), or an alfalfa/intermediate wheatgrass mixture (fertilized; MIX). Wheat performance (yield, 1,000 kernel weight [TKW], and crude protein [CP] concentration), and associations between 11 plant available soil mineral concentrations and 11 wheat grain mineral concentrations were assessed. Wheat following alfalfa had greater yield than all treatments, greater TKW than CSW, greater CP than IWG and CSW, but lower grain Zn concentration than IWG (p ≤ .05). Wheat grain following IWG had greater Fe and Mn concentration than MIX, greater Mg concentration than CSW, and lower S concentration than all treatments (p < .05). Multivariate correlation analysis showed positive correlations between plant available soil and grain B, Mg, Mn, and S concentrations (p ≤ .02), while plant available soil and grain Zn and Ca concentrations showed negative associations (p ≤ .05). Rotating perennial forage phases into wheat cropping systems increased wheat yield and CP but reduced certain plant available soil minerals. Although rotating perennials into annual cropping systems can benefit some soil quality parameters it may also diminish plant available soil minerals, influencing fertility recommendations.

土壤有效矿质元素浓度与小麦籽粒矿质元素浓度之间的关联常被默认存在，但鲜有研究对这类关联展开实证考察。本研究采集了2006至2011年间北美大平原北部半干旱旱地作物种植田间试验中的土壤与小麦籽粒样本。本试验设置了4种前茬处理：施肥条件下的连续春小麦（普通小麦*Triticum aestivum* L.，简称CSW）、5年生苜蓿（*Medicago sativa* L.）多年生牧草轮作后种植小麦、5年生施肥中间偃麦草（*Thinopyrum intermedium* (Host) Barkw. & D.R. Dewey subsp. *Intermedium*，简称IWG）多年生牧草轮作后种植小麦，以及5年生施肥苜蓿与中间偃麦草混合牧草（简称MIX）轮作后种植小麦。本研究评估了小麦生长性能指标（产量、千粒重[Thousand Kernel Weight, TKW]与粗蛋白[Crude Protein, CP]浓度），以及11项土壤有效矿质元素（plant available soil mineral）浓度与11项小麦籽粒矿质元素浓度之间的关联。试验结果表明，苜蓿前茬小麦的产量显著高于其余所有处理组；其千粒重高于连续春小麦组，粗蛋白浓度高于中间偃麦草前茬组与连续春小麦组，但籽粒锌（Zn）浓度低于中间偃麦草前茬组（p ≤ 0.05）。中间偃麦草前茬小麦的籽粒铁（Fe）与锰（Mn）浓度高于混合牧草前茬组，镁（Mg）浓度高于连续春小麦组，而硫（S）浓度低于所有处理组（p < 0.05）。多元相关分析显示，土壤有效态与籽粒中的硼（B）、镁（Mg）、锰（Mn）及硫（S）浓度呈显著正相关（p ≤ 0.02）；而土壤有效态与籽粒中的锌（Zn）及钙（Ca）浓度呈显著负相关（p ≤ 0.05）。将多年生牧草轮作阶段纳入小麦种植体系，可提升小麦产量与粗蛋白浓度，但会降低部分土壤有效矿质元素含量。尽管将多年生作物纳入一年生种植系统可改善部分土壤质量参数，但也可能减少土壤有效矿质元素储备，进而影响农田施肥推荐方案。