Published online by Cambridge University Press: 24 January 2011
Introduction. While researchers have paid considerable attention to theeffect of soil salinity on crop yield, methodological impediments remain when salinity iscombined with other growth factors, especially in farmers’ fields. A specific methodologywas adapted to assess the effect of waterlogging and salinity on date palm yield(Phoenix dactylifera L. cv. Deglet Noor). Materials andmethods. Date palm yield, water table depth, irrigation water, groundwater andsoil salinity were measured in 167 field plots located in five irrigation sectors of theWargla basin (Algeria). Variance analysis and a boundary line approach were combined toanalyze actual and potential yields according to environmental stresses. Results anddiscussion. High soil salinity resulted from saline irrigation water and ashallow water table. Actual yield decreased with the increase in soil salinity, thedecrease in water table depth, and the presence of a gypsum-cemented horizon within thesoil profile. The significant effect of the interaction between water table depth and soilsalinity showed that the crop responded to the most severe stress rather than tocombinations of the individual effects. Potential yield was assessed according to classesof water table depth, soil salinity and the occurrence of a gypsum-cemented horizon. Therelationship between soil salinity and potential yield was calibrated according to twomodels. The limiting factors in order of decreasing importance were shallow water table,high soil salinity and occurrence of a gypsum-cemented horizon for 38.3%, 16.8% and 2.4%of the field plots, respectively; there was no limiting factor for 42.5% of the fieldplots. In certain sectors, actual yields remained far below potential yields and theadditional effect of irrigation water salinity could thus be considered.