Impact of Soil Salinity and Phosphorus Fertility on Wheat Plant : ROLE OF PHOSPHORUS FERTILIZATION IN ALLEVIATION ADVERSE EFFECTS OF SALINITY ON WHEAT GROWN ON DIFFERENT SOIL TYPES

Optimum fertilization management is an important technique to alleviate the adverse effects of salinity stress on plants. An experiment was conducted to evaluate the ameliorative role of inorganic and organic P-sources on wheat grown under salt stress in three soil types deficient in available P. Wheat plants were grown on alluvial, sandy and calcareous soils under salinity levels of 4, 8 and 12 dS/m of saturated paste extract (ECe) and supplied with constant rate of superphosphate (SP), cattle manure (CM) and 1:1 mixture of SP and CM. The results revealed that plants grown on the sandy soil were more susceptible to the adverse effects of salinity compared with that planted on the alluvial one, especially at 0 P. However, plants grown on the calcareous soil were moderately affected. In addition, varying soil type caused significant differences in the aboveground biomass and uptake of N, K, P and Zn in shoots and grains, where maximum values were attained in the alluvial soil followed by calcareous soil. Grains and straw yields and contents of N, P and K in the shoot tissue, grains and straw decreased significantly with increasing ECe from low (4 dS/m) to high level (12 dS/m).