Grain yield and water use: Relative performance of winter vs. spring cereals in east-central Saskatchewan

Changing economic conditions have provided strong incentives for grain prod ucers to choose the most profitable cereal crops to grow. We determined gra in yield and water use efficiency (WUE) for winter wheat (Triticum aestivum L.), fall rye (Secale cereale L.), hard red spring (HRS) wheat, Canada pra irie spring (CPS) wheat, amber durum (Triticum turgidum L.), and barley (Ho rdeum vulgare L.) under no-till systems. Over 60% of yield variability exis ting among site/years was due to water use or evapotranspiration (ET) in se miarid east-central Saskatchewan. Mean grain yield increased by 16.3 kg ha( -1) with each millimetre of increase in ET. Barley produced 3748 kg ha(-1) of grain on average, or 21% higher than winter wheat, 27% higher than CPS w heat, 39% higher than rye or durum, and 50% higher than HRS wheat. Average yields differed less than 5% between winter wheat and CPS wheat, but in wat er-stressed environments, CPS wheat had 19 to 34% lower grain yield than wi nter wheat. In one of the five cases where winter wheat was seeded much lat er than the recommended seeding date, CPS wheat yields were 16% higher than winter wheat. With every millimetre of increased ET, CPS or barley increas ed grain yield by 22 kg ha(-1), while winter wheat increased yield by 17 kg ha(-1). Winter wheat and rye had no yield differences in general, but in m ore moist environments, winter wheat produced higher (up to 28%) grain yiel d than fall rye, and in the year when winter wheat was seeded late, winter wheat yielded 11% lower than rye. As fertiliser N increased from 50 to 100 kg ha(-1), barley grain yield increased by 347 kg ha(-1), and durum grain y ield increased by only 5 kg ha(-1). Winter wheat, fall rye and barley had g reater WUE than the other spring cereals, but soil profile (0-120 cm) water in the spring did not differ among crops. In maximising grain yield and wa ter use in east-central Saskatchewan, barley, winter wheat, and CPS wheat w ould provide the best options.