Rotation Impact on On‐Farm Yield and Input‐Use Efficiency in High‐Yield Irrigated Maize–Soybean Systems

Abstract

Cereal yields tend to be higher in cereal–legume rotations relative to cereal monoculture yields. We investigated the influence of crop rotation on yield and input‐use efficiency in high‐yield irrigated maize (Zea mays L.)‐based cropping systems using producer‐reported data from western U.S. Corn Belt (about 11,000 observations). Across regions, average yield of maize grown after soybean [Glycine max (L.) Merr.] (S–M) was 0.2 to 0.6 Mg ha−1 (2–5%) higher, relative to yield of maize grown after maize (M–M). Soybean yield was 5% greater after two consecutive maize crops (M–M–S) than after only 1 yr of maize (S–M–S). Nitrogen fertilizer rate in maize fields was 13 kg N ha−1 (6%) lower in S–M than M–M fields, which, together with higher maize yields in S–M fields, resulted in 11% higher nitrogen partial factor productivity (PFPN). Difference in PFPN was unrelated with residual soil N–NO3− from prior crop. Analysis of rotation data indicated that rotation effect persists across a wide range of maize yields, from 6 to 15 Mg ha−1, though magnitude of rotation effect decreases with increasing yield level. Trends toward greater proportion of total maize area in S–M, rather than M–M, accounts for 8% of maize yield gain in U.S. Corn Belt since 1970. Similarity between our findings and previous research highlights the opportunity to quantify impact of management on yield and efficiencies by using producer data as a complement to high‐cost multi‐year, multi‐site field experiments.Core Ideas We assessed rotation effect on on‐farm yield and input‐use efficiency. Analysis was based on a large producer‐reported database collected from high‐yield irrigated maize–soybean systems. There was a consistent positive rotation effect on yield and partial factor productivity for N fertilizer. Number of previous maize crops did not affect maize yield in monoculture but soybean yields were higher following multiple maize crops. Increasing maize area in rotation relative to monoculture accounts for 8% of the maize yield gain in the U.S. Corn Belt since 1970.

Agronomic and Economic Benefits of Rotating Corn with Soybean and Spring Wheat under Different Tillage in Eastern Canada

“…Averaged across the 5 yr, the yields for soybean grown once every 3 yr were greater (+0.20 Mg ha −1 ) than those for S‐S‐S, whereas the 2‐yr C‐S rotation resulted in intermediate yields. Our results agree with soybean yields reported in Iowa and Nebraska after 2 consecutive years of corn (Al‐Kaisi et al, 2016; Farmaha et al, 2016). In addition, several studies indicated that, in most situations, soybean grain yield was improved (+0.40 Mg ha −1 on average) when the C‐S rotation was diversified with winter wheat (Gaudin et al, 2015b; Marburger et al, 2015; Kazula and Lauer, 2018).…”

“…This agrees with the recent study of Al‐Kaisi et al (2015) in Iowa, who found that a 10‐yr C‐S rotation resulted in greater corn yields than C‐C‐C or C‐C‐S. Farmaha et al (2016) also reported an average yield increase of 0.2 to 0.6 Mg ha −1 for corn grown after soybean compared with C‐C‐C when compiling producer‐reported data (11,400 observations) from irrigated fields in Nebraska. In Wisconsin, Kazula and Lauer (2018) reported that corn in a 3‐yr rotation with soybean and winter wheat yielded 1.5 and 0.9 Mg ha −1 more than C‐C‐C or C‐S rotation, respectively.…”

Estimating yield gaps at the cropping system level

“…However, important improvements in productivity also are likely to come from innovations at the cropping or farming system levels ( Rodriguez and Sadras, 2011 ). In temperate rainfed agriculture, where rainfall and temperature constrain the system to a single crop per year, crop rotations are particularly relevant to farm-level production ( Angus et al, 2015 , Farmaha et al, 2016 ). In environments with a longer growing season where multiple cropping is feasible, capture of resources and yield are often improved through the processes of facilitation and niche differentiation in time and space ( Brooker et al, 2014 , Gaba et al, 2014 , Li et al, 2007 , Malézieux et al, 2009 ).…”

Long term crop rotation effect on soybean yield explained by soil- and root-associated microbiome and soil health indicators

“…Our results showed that following 14 years of continuous corn, soybeans had a higher yield when compared with the other preceding crop sequences. A recent study conducted by Farmaha, et al 51 stated that soybean yield in an irrigated corn-corn-soybean rotation was higher than in a soybean-corn-soybean rotation. The results from our study expanded the conclusion that two or more previous years of corn crop sequences resulted in increased soybean yield as compared to one previous year of corn crop sequences.…”