Diversification improves the performance of cereals in European cropping systems

Abstract

In the face of climate change, cropping systems need to achieve a high performance, providing food and feed and adapting to variable environmental conditions. Diversification of cropping systems can support ecosystem services and associated biodiversity, but there is little evidence on which temporal field arrangement affects the performance of crop yields (productivity and stability), partly due to a lack of long-term data and appropriate indicators. The objectives of this study were to quantify the effect of cropping system diversification on yield stability, environmental adaptability, and the probability of diversified systems to outperform less diverse cereal-based systems in Europe. Spring and winter cereal yields were analyzed from long-term field experiments from Sweden, Scotland, and France. We investigated diversification through (i) introduction of perennial leys, (ii) increasing the proportion of ley in the rotation, (iii) varying the order in which crops are positioned in the rotation, (iv) introduction of grain legumes, and (v) introduction of cover crops. The results showed that cereal crops within cropping systems incorporating perennial leys outperformed systems without leys in 60–94% of the comparisons with higher probabilities at low fertilizer intensities. The yield stability of oat did not differ, but mean yields were 33% higher, when grown directly after the ley compared to oat grown two years later in the crop sequence under similar management. Durum wheat grown in a cropping system with grain legumes had higher yields in lower-yielding environmental conditions compared to rotations without legumes. Diversification with cover crops did not significantly affect yield stability. We conclude that diverse cropping systems can increase cereal productivity and environmental adaptability and are more likely to outperform less diverse systems especially when introducing perennial forage legumes into arable systems. Effects of diversification on cereal yield stability were inconsistent indicating that higher productivity is achievable without reducing yield variability. These novel findings can support the design of more diverse and high-performing cropping systems.

Diverse systems and strategies to cost-effectively manage herbicide-resistant annual ryegrass (Lolium rigidum) in no-till wheat (Triticum aestivum)-based cropping sequences in south-eastern Australia

“…It is well documented that the inclusion of either legume or brassica break crops in cropping sequences can enhance subsequent wheat yields; especially where soil N availability and/or disease are constraints to productivity (Kirkegaard et al 2008;Angus et al 2015;Ladha et al 2022;Reckling et al 2022;Zhao et al 2022). However, the on-farm studies reported here indicated that broadleaf break crops can also contribute to increased grain yields by facilitating the reduction of ARG weed pressure.…”

Future area expansion outweighs increasing drought risk for soybean in Europe

“…Bradyrhizobium ) needs to be improved, especially under cool weather conditions (Halwani et al, 2021; Kühling et al, 2018; Zimmer et al, 2016), (iii) farmers need to have the knowledge and markets to sell crops within their region at attractive prices and (iv) human diets need to change to reduce the demand for soybean‐based feed for ruminants. Second, climate change adaptation and low‐pesticide strategies promote diversification of the cropping system (Reckling et al, 2022) as an important pillar, and soybean—as a nitrogen‐fixing legume—offers a range of environmental benefits that have already increased the crop's appeal.…”

Higher crop diversity in less diverse landscapes

“…Diversification of landscapes and cropping practices have been extensively studied in recent years to strengthen sustainability within the agricultural landscape. Various studies reported its benefits for biodiversity conservation (Honnay et al, 2003;Martínez-Núñez et al, 2023;Tscharntke et al, 2021), yield regulation (Galpern et al, 2020;Nguyen et al, 2022;Reckling et al, 2022), and maintenance of ecosystem services (Rusch et al, 2016;Tamburini et al, 2020). However, because land is limited, for landscape planning one needs to address landscape multifunctionality to produce food and energy, and provide habitats and other ecosystem services.…”