Lentil enhances the productivity and stability of oilseed-cereal cropping systems across different environments

Abstract

Abstract Enhancing the stability of crop production is vital for agriculture under climate uncertainty. Conventional fallow and shallow-rooting pulse crops such as lentil (Lens culinaris Medic.) have been incorporated in oilseed-cereal cropping systems to cope with dry conditions on the semiarid Canadian prairies. However, the static and dynamic stability of these adaptation practices at a cropping system level is unclear due to the complexity of interactions. This study assessed the effects of diversified rotation systems as drought adaptation practices on the productivity and stability of oilseed-cereal cropping systems. Nine 3-year crop rotations were tested for two cycles at three sites from 2013 to 2016. The 3-year crop sequences included fallow, lentil, and spring wheat (Triticum aestivum L.) in rotation phase 1, followed by canola (Brassica napus L.), oriental mustard (Brassica juncea L.), and camelina (Camelina sativa L. Crantz) in phase 2, and the rotation phase 3 was durum wheat (Triticum turgidum L. subsp. durum (Desf.) Husn.) in all nine rotation systems. On average, the lentil system increased system productivity, expressed by annualized durum wheat equivalent yield, by 24% and 78% compared with the spring wheat and fallow systems, respectively. Stability analysis revealed that the lentil – B. juncea – durum wheat and lentil – B. napus – durum wheat systems had the least variation across the environments and were well adapted to high-yielding sites. The fully-phased rotations across various environments showed that the drought-induced reductions in system productivity ranged from 3 to 47% compared with yields under normal weather, with the lentil – oilseed – durum systems having least reduction. Quantitative assessments revealed that about 36% of the variation in system productivity was associated with rotation systems and additional 30% was due to weather-related factors. In conclusion, the inclusion of lentil in rotation increases systems productivity and reduces yield variation in oilseed-cereal cropping systems in changing environments.