Field experiments were conducted from 1979 to 1982 in southern Alberta to determine the seasonal water use of soybeans. Soil moisture was determined every 5–6 days throughout the growing season and irrigation water was applied when soil moisture tension in the top 30 cm reached −40 kPa, with an additional treatment of −60 kPa for 1980 and 1981. Seasonal water use in a year of normal growth (1980) varied from 426 to 482 mm for the drier and wetter treatments, respectively. The drier treatments in 1980 and 1981 resulted in more efficient use of water. Low early-season water use with peak use after full pod development (R4) was defined. Water use peaked in late July to early August with a requirement of 7 mm/day. Small changes in seed quality, tending towards higher protein and lower oil under wetter conditions, are corroborated in the literature. The possibility of integrating crop and cultivar selection with appropriate irrigation management to improve production efficiency in southern Alberta is discussed. The late-peak water requirement of soybeans combines well with the early-peak use of cereal crops to ensure efficient seasonal irrigation management.Key words: Glycine max (L.) Merr., évapotranspiration, seed protein, seed oil
Do Water Contamination Reports Influence Water Use Practices on Feedlot Farms and Rural Households in Southern Alberta?
