Optimal Seeding Rates and Disease Management for Yield and Quality in Faba bean (Vicia faba L. minor)

Abstract

Faba bean (Vicia faba L.) production has remained extremely low, compared to pea and lentil, in the Canadian Prairies due to agronomic and economic barriers. These barriers can be overcome, if a consistent, high yielding and high quality faba bean crop is produced annually. This can be achieved by updating the best management practices for the dark brown and black soil zones of Saskatchewan, where faba bean is primarily produced. The objective of the first experiment is to identify the optimal seeding rate required to maximize yield in three faba bean varieties. The objective of the second experiment is to identify the optimal disease control practices required to minimize disease severity, and increase yield and quality, in two faba bean varieties. In the seeding rate experiment, CDC Snowdrop, CDC SSNS-1, and FB9-4 were seeded at 5 different rates between 20 and 100 viable seeds m-2 in 2015 and 2016, and 5 to 60 viable seeds m-2 in 2017. Results indicate that within the black and dark brown soil zones of Saskatchewan, maximum agronomic faba bean yields can be found between 49 and 54 viable seeds m-2, while economic yields can be found at 45 viable seeds m-2. There were no significant differences in the seeding rate required to achieve maximum yields of the three varieties tested. Therefore, results indicate that 50 viable seeds m-2 is required to maximize yield, quality, and profitability for all faba bean varieties and seed sizes cultivated in Saskatchewan. In the disease control experiment, chlorothalonil, fluxapyroxad + pyraclostrobin, fluopyram + prothioconazole, and penthiopyrad fungicides were applied at 10%, 50%, and 10+50% flower, and compared to an untreated control, on CDC Snowdrop and CDC SSNS-1 varieties. Due to the environmental conditions and low disease severity experienced throughout the experimental period, both varieties had minimal responses to fungicide application. Results suggest that all four fungicide products tested, can be equally effective to maintain or improve faba bean yield and quality when disease severity is low. Overall, the results of this thesis can be used to update two components in the set of best management practices for faba bean cultivation in Saskatchewan.