The effect of fertilizer management on yield of crop plants in Pakdasht region

The objective of this research was to study the effect of fertilizer management on the yield increase of crop plants. The extra amounts of applied fertilizers were studied by comparison between allocated, applied and recommended fertilizers’ amounts for: wheat, barley, corn and alfalfa with four replicates and the other data was gathered via questionnaires. Soil analysis of phosphorus, potassium and nitrogen amounts was performed in 20 fields and analysis of data was conducted base on complete randomized block design. Comparison of the averages was showed that there were significant differences between the amounts of allocated, applied and recommended fertilizers (P? 0.05). The average amounts of extra applied and extra distributed fertilizers were 382.9 and 150.6 Kg.ha-1 more than the recommended amounts, respectively. However, there was no significance increase in yield. 12 and 28% of farmers used the fertilizers in the basis of recommended and allocated, respectively and 60% of them used more than recommended amounts. Excess fertilizer application due to improper management causes reduction of soil and water quality.