Add Yahoo as a preferred source to see more of our stories on Google. BISMARCK, N. D. (AP) -- Tennessee farmer Todd Littleton expects to pay $100,000 more for fertilizer this season, a 40% spike from his bill last year thanks to the war in Iran -- and he is scrambling to cover that extra cost.

The same shipping bottleneck in the Strait of Hormuz that is roiling oil markets is causing "immediate volatility" in liquid fertilizer prices, according to Jefferies analyst Laurence Alexander.

Concerns over potential disruptions in the Strait of Hormuz are leading farmers to worry about supply shortages and further price spikes for essential fertilizers like nitrogen.