Effects of Bedding Preparations on Potato Yield and Greenhouse Gas Emissions in Southern Alberta, Canada

Fall bedding, a prevalent practice for potato (Solanum tuberosum) production in southern Alberta, entails fall-season soil preparations including irrigation, fertilization, plowing, and bed formation. This approach, while economically advantageous - owing to reduced labor and fertilizer costs and a decrease in other necessary preparations during fall - raises environmental concerns. Specifically, the lag between fertilizer application and crop nutrient uptake may lead to elevated emissions of carbon dioxide (CO₂) and nitrous oxide (N₂O), potent greenhouse gases.

To investigate these potential environmental impacts and assess potato yield outcomes, a field study was conducted in Lethbridge, Alberta. This experiment utilized 36 plots with different combinations of bedding approaches (fall bedding, spring bedding, and spring bedding following a winter cover crop), two irrigation levels (80% and 120% of AIMM recommended rates), and both fertilized and unfertilized conditions. Each combination was replicated three times.

Findings show that N₂O emissions are strongly influenced by fertilizer application (P < 0.005), the timing of bedding (P < 0.05) and field position (hill or furrow) (P < 0.05), with the highest emissions observed in fall-bedded plots under high irrigation and fertilization. In contrast, CO₂ emissions were less variable, although highly significant differences were observed primarily between hill and furrow positions (P < 0.0005). Furthermore, variations in bedding practices and fertilization both significantly affected tuber yields (P < 0.05), underscoring the need to balance production practices with environmental considerations in potato cultivation.