Effects of early season waterlogging on maize growth and yield

Abstract

Five irrigation treatments (0, 2, 6 and 24 h ponding in furrows plus a 6-h flooded treatment) were applied at the first two irrigations after emergence of a maize crop. Water was ponded for 6 h in the furrows or on the flooded plots at each of the 10 subsequent irrigations.The irrigation treatments had a significant effect on plant growth, resulting in final DM yields of 22.3, 19.7, 19.2, 18.7 and 13.9 t/ha for the 0, 2,6, 24 h furrow irrigations and the 6 h flood treatment respectively. The 2, 6 and 24 h furrow treatments did not perform differently in any of the parameters measured, indicating that a threshold level of waterlogging was reached in all three compared with the zero ponding treatment.Nitrogen applications of 25 kg N/ha to the soil or foliage prior to each of the first two irrigations did not reduce the severity of the waterlogging treatments, despite herbage N levels being significantly depressed in the flooded plots. Similarly, soil fungicide application did not mitigate the waterlogging effects.Individual plants within the treatment populations differed greatly in their response to the waterlogging treatments. The effect on individual plants persisted until final harvest. Cultural methods which may prevent the yield losses associated with the first irrigation of maize are discussed.