Waterlogging severely retards P use efficiency of spring barley (Hordeum vulgare)

Efficient utilization of various phosphorus (P) sources for producing optimum yields in P‐deficient conditions requires knowledge of best management under changing weather conditions. In this study, barley ( Hordeum vulgare ) was grown in an extremely P‐deficient soil with variable moisture conditions. During a wet growing period, utilization of P from dairy cow manure ( DCM ), fox manure ( FM ) and meat and bone meal ( MBM ) was compared with the utilization of P from superphosphate ( SP ) with concomitant effects on grain yield and quality. High P application rates were necessary to compensate for severe yield losses due to waterlogging. Only 7 kg P/ha was required for optimum yield in less waterlogged conditions, while 43 kg P/ha was needed in waterlogged conditions. In both moisture conditions, broadcast DCM ‐P increased grain yield similar to banded SP ‐P, although P acquisition was lower in early growth stages. FM ‐P and MBM ‐P were less efficiently utilized. Waterlogging also depressed yield quality when P was applied. Extreme rainfall events are predicted to become more frequent at northern latitudes. As an alternative to higher P fertilizer rates, improving soil drainage could be a favourable, long‐term measure for better utilization of applied P and soil P resources, even at very low soil P status.