Share prices of grain-based foods companies fell sharply today.

NEW YORK — Share prices of grain-based foods companies fell sharply today, swept up in the sell-off that has gripped global equity markets.

In trading on the New York Stock Exchange and on Nasdaq, shares of 24 of the 26 companies in the grain-based foods share index lost ground.

While almost every company in the index sustained a decline of 1% or greater, only three companies in the index fell by a wider margin than the 4% decline sustained in the S.&P.500. Panera Bread Co. shares fell 4.1%; Seaboard Corp. slumped 5.6%; and Starbucks Corp. dropped 4.8%.

The two largest publicly traded baking companies both were hit in the sell-off. Flowers Foods, Inc. shares were down 3.7%. Grupo Bimbo shares were down 3.3%.

Two companies in the grain-based foods index posted gains Aug. 24 — MGP Ingredients, Inc., up 4.8%; and Treehouse Foods, Inc., up 0.1%.

The smallest declines for the day were sustained by Bunge Ltd., down 1%; Bridgford Foods Corp., down 1.4%; Dunkin’ Brands Group, Inc., down 0.7%; The Hain Celestial Group, Inc., down 0.4%; J&J Snack Foods Corp., down 1.8%; Snyder’s-Lance, Inc., down 1.8%; and The J.M. Smucker Co., down 1.6%.

Other companies to fall sharply included Archer Daniels Midland Co., down 3.5%; ConAgra Foods, Inc., down 3.5%; Campbell Soup Co., down 3.3%; Ingredion, Inc., down 3.5%; and Post Holdings, Inc., down 3.8%.

The Dow Jones average of industrial shares fell 588.47 points, or 3.6%.