Soybeans have become an integral part of the cropping mix on Manitoba farms, with soybean seeded acreage expanding to a record 1.6 million acres in 2016. Because the acreage has grown so rapidly, relatively little information is available regarding the longer-term effects of including soybean in current cropping systems. A better understanding of the effects of crop rotation on factors including crop productivity, root rot severity, and economic risk and returns may help growers identify those rotations that optimize agronomic and economic performance in the longer-term.
Crop rotation is a cornerstone of crop production systems, and can have a significant effect on a host of factors including plant disease, pests, nutrient availability, crop productivity, and economic performance. While the return on investment to this type of research is not immediate, assessing crop rotations in small-plot studies can provide agronomic and economic information as to which systems might maximize overall benefits and profitability on-farm, and reduces the need for growers to experiment with rotations that could negatively affect productivity in the short- and long-term.
The objective of this study is to determine the effect of rotation length and crop sequence on root rot, crop yield and quality, nutrient cycling, and on economic returns and risk for individual crops and the entire rotation over time. In order to achieve this objective, funding is being requested to allow the continuation of a soybean-based cropping system study that was initiated as part of a crop sequence study supported by the Manitoba Pulse and Soybean Growers. This study was established in spring 2014 on a Newdale clay loam soil located north of Brandon, MB. This randomized, replicated study includes five rotations: soybean-canola; soybean-wheat; soybean-wheat-canola; soybean-canola-wheat; soybean-soybean-wheat, with each phase of each rotation present each year.