A report at www.arkansas-crops.com  by Gus Lorenz, Arkansas Extension entomologist, addresses the causes of “pecky” rice.
“There is a lot of literature out there that tells us pecky rice is associated with stink bugs certainly but also with several fungi and bacterial diseases,” writes Lorenz. “I guess anything that causes a spot to appear on a rice kernel could be the causal agent for peck. So while most of us associate pecky rice solely with stink bugs, this is not entirely accurate. According to the literature there are at least 5 or 6 different fungi (probably more) that can also cause this condition on rice.”
To access Lorenz’ full report, see here.