Cover crop (CC) species selection can contribute to reducing soil penetration resistance (brassica species), improved soil nitrogen (N) cycling (legume species), and suppression of weeds (grass species). However, one of the main concerns about including CCs in water-limited environments is soil water use and the consequences to subsequent crops. To determine the effects of individual CC species under water-limited environments, we evaluated fall and spring CC biomass produced, and soil water and N content, penetration resistance, weed density and biomass during the maize growing season, and maize grain yield. The experiment was conducted under a winter wheat-maize-fallow rotation at two locations (North Platte and Grant, NE) during 2016−2017 and 2017−2018 (four site-years). Treatments consisted of seven popular CC species plus a control (fallow), planted after winter wheat harvest. Spring oats, Siberian kale, and purple top turnip produced greater fall biomass, while cereal rye produced the greatest amount of spring biomass. However, cereal rye reduced soil volumetric water content in North Platte 2016−2017 and increased soil penetration resistance from 20–30 cm soil depth across site-years likely due to soil water use. Spring cover crop growth suppressed weeds early in the maize growing season. Due to its aboveground biomass production, cereal rye decreased weed density and biomass by 80 and 88 %, respectively, compared to the fallow treatment. On the other hand, except for brassicas, CCs decreased N levels in the soil during maize growing season, and all CC species reduced maize grain yield up to 30 % compared to fallow (except spring oats). Spring oats can be an alternative to cereal rye as CC species for semi-arid regions. However, since CCs did not promote any maize yield gain, our findings suggest that producers should use caution when incorporating CCs in their cropping systems in water-limited environments. This research provides valuable information on the potential impact of CCs on rainfed maize production, as well as help producers and agronomists develop better CC management programs for cropping systems in semi-arid regions.

覆盖作物 (CC) 物种选择有助于降低土壤渗透阻力（芸苔属物种）、改善土壤氮 (N) 循环（豆类物种）和抑制杂草（草物种）。然而，在缺水环境中包括 CC 的主要问题之一是土壤水分的利用及其对后续作物的影响。为了确定单个 CC 物种在缺水环境下的影响，我们评估了秋季和春季 CC 生物量的产生，以及玉米生长季节的土壤水和 N 含量、渗透阻力、杂草密度和生物量，以及玉米籽粒产量。该试验是在 2016-2017 年和 2017-2018 年（四个地点年）的两个地点（北普拉特和格兰特，内布拉斯加州）在冬小麦-玉米-休耕轮作下进行的。处理包括七种流行的 CC 物种和一个对照（休耕），冬小麦收获后播种。春燕麦、西伯利亚羽衣甘蓝和紫顶萝卜产生更大的秋季生物量，而谷物黑麦产生的春季生物量最大。然而，谷物黑麦在 2016-2017 年期间降低了北普拉特的土壤体积含水量，并可能由于土壤水分的使用而增加了 20-30 厘米土壤深度的土壤渗透阻力。春季覆盖作物的生长抑制了玉米生长季节早期的杂草。由于其地上生物量的产生，与休耕处理相比，谷物黑麦使杂草密度和生物量分别降低了 80% 和 88%。另一方面，除芸苔属植物外，CCs 在玉米生长季节降低了土壤中的 N 水平，与休耕（春燕麦除外）相比，所有 CC 物种使玉米籽粒产量降低了 30%。春燕麦可以替代谷物黑麦作为半干旱地区的 CC 物种。然而，由于 CCs 不会促进任何玉米产量增加，我们的研究结果表明，生产者在缺水环境中将 CCs 纳入其种植系统时应谨慎行事。这项研究提供了关于 CCs 对雨养玉米生产的潜在影响的宝贵信息，并帮助生产者和农艺师为半干旱地区的种植系统制定更好的 CC 管理计划。