WEST LAFAYETTE, Ind. (AP) — An Indiana agricultural expert says declining power plant emissions are apparently reducing the amount of an important nutrient corn plants get through rainfall.

Purdue Extension soil fertility specialist Jim Camberato says Indiana’s rainfall used to contain a lot of sulfur from coal-fired power plant emissions.

But he says the amount of sulfur reaching corn through rainfall or the air has fallen to the point where plants are now apparently not getting enough of the nutrient that way.

The federal government says the amount of sulfur absorbed into the soil from rainfall fell by an average of 62 percent in the eastern U.S. from 1989 to 2013 as pollution controls got tougher.

Camberato says corn plants that don’t get enough sulfur develop yellow, green-yellow or yellow-white striping on their leaves.