Scotiabank's Agricultural Index dropped by just over 1 per cent in April from March.
The bank says higher barley, canola and cattle prices were more than offset by softer wheat and hog prices.
The April agricultural index was down over 19 per cent from April of 2014.
Scotiabank points out the USDA is forecasting another year of high world output and declining prices for wheat, corn and soybeans for the 2015-16 crop year.
The bank's overall commodity price index was up almost 2 per cent in April on the strength of rebounding oil and base metal prices.
