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Abstract
In the drier areas of Syria yields of barley, the principal crop, are low. Due to the
variability in rainfall, fertilizer use is perceived as risky. Barley-fertilizer trials have been
conducted on farmer's fields over a period of four years to investigate whether the large
yield response to fertilizer observed on research sites could be achieved under farmers'
conditions. Data were pooled across years and sites and response functions estimated.
Simple optimization analysis shows that economic optimum fertilizer rates vary considerably
with rainfall and relative prices. Historical rainfall data are combined with the
estimated response functions, and stochastic dominance analysis is used to compare the
riskiness of fertilizer treatments in terms of net benefits and benefit-cost ratios. Results
show that, given the estimated expected rainfall in barley producing areas, fertilizer use,
especially at low levels, may not be as risky as has been believed. Extensions of the
methodology to include other environmental variables, or to target recommendations, are
discussed.