Evaluation of species selection and management decisions for fall seeded cover crops in Manitoba
| dc.contributor.author | Janzen, Virginia | |
| dc.contributor.examiningcommittee | Entz, Martin (Plant Science) | |
| dc.contributor.examiningcommittee | Bullock, Paul (Soil Science) | |
| dc.contributor.supervisor | Lawley, Yvonne | |
| dc.date.accessioned | 2024-01-22T20:30:45Z | |
| dc.date.available | 2024-01-22T20:30:45Z | |
| dc.date.issued | 2023-12-03 | |
| dc.date.submitted | 2023-12-04T05:20:03Z | en_US |
| dc.date.submitted | 2024-01-22T18:04:14Z | en_US |
| dc.degree.discipline | Plant Science | en_US |
| dc.degree.level | Master of Science (M.Sc.) | |
| dc.description.abstract | There is limited local research available on cover crops in the eastern Canadian Prairies, including Manitoba. Cover crops are an agronomic practice in which plants are used to cover the soil for ecosystem benefits, rather than for market. Cover crops are often seeded and managed outside the conventional growing season, as to not displace cash crops. Ecosystem benefits (e.g. soil erosion control, N retention, weed suppression) can only be realized when there is sufficient cover crop establishment and growth. Cover crop performance depends on the overlapping influences of species selection and management decisions made in the context of a particular location. The limitations of GDD accumulation and precipitation amounts and timing in Manitoba present unique challenges when making cover crop decisions. The objective of this thesis was to compare cover crop decisions and to evaluate how these decisions affected the performance of different fall seeded cover crops in Manitoba. In addition, the impact of fall seeded cover crops on following cash crops was determined. This was achieved through three research studies. The first research study compared seven cover crop species, plus one mixture, seeded at three different dates in the fall. Two site-years were dry and two site-years were wet. Emergence, biomass production, C:N ratio, and ground cover were similar between winter killed cool season cover crop species when seeded around September 1. The second research study evaluated the effects of fall seeded cover crops on a spring wheat (Triticum aestivum L.) test crop. Three cool season annuals, one winter annual, and one cover crop mixture were seeded in the fall. Winter killed cover crops had no effect on the test crop. Fall rye (Secale cereale L.) and the mixture that contained fall rye had a negative effect on wheat density and wheat yield. The third research study compared fall rye cover crop termination timings prior to soybean (Glycine max (L.) Merr.) and edible bean (Phaseolus vulgaris L.). Managing the living cover crop in the spring with strip tillage removed the soybean yield penalty caused by late fall rye termination but only slightly improved edible bean yield. These results highlight the opportunity for using winter killed fall seeded cover crops in Manitoba with minimal risk to a following small grain crop. Fall rye used as a cover crop prior to spring wheat and edible bean requires termination prior to planting. Soybean can be planted green into fall rye with strip tillage. Results from this research show that there are opportunities for fall seeded cover crops in Manitoba cropping systems and will provide guidance for cover crop decision making. Future research under these environmental conditions should explore cover crop performance and thresholds for ecosystem benefits in Manitoba. | |
| dc.description.note | February 2024 | |
| dc.identifier.uri | http://hdl.handle.net/1993/38002 | |
| dc.language.iso | eng | |
| dc.rights | open access | en_US |
| dc.subject | cover crop | |
| dc.subject | cover crops | |
| dc.subject | fall rye cover crop | |
| dc.subject | fall seeded cover crop | |
| dc.subject | cover crop termination | |
| dc.subject | cover crop seeding | |
| dc.title | Evaluation of species selection and management decisions for fall seeded cover crops in Manitoba | |
| dc.type | master thesis | en_US |
| local.subject.manitoba | yes |