Is high-fructose corn syrup behind honeybee's colony collapse disorder?

My post yesterday on honeybees' colony collapse disorder prompted my wife Sally to point out that I'd missed an intriguing post on the same subject by my friend, the brilliant investigative reporter Andrew Schneider.

Andrew reports on new research that points to beekeepers' use of high-fructose corn sweetener as a possible culprit in the die-off  of something like half the honeybees used for commercial pollination of crops in this country.

It seems that a toxin can be produced when high fructose corn sweetener is manufactured. As the abastract of the study just published in the Journal of Agricultural and Food Chemistry points out:

In the United States, high-fructose corn syrup (HFCS) has become a sucrose replacement for honey bees and has widespread use as a sweetener in many processed foods and beverages for human consumption. It is utilized by commercial beekeepers as a food for honey bees for several reasons . . .  Hydroxymethylfurfural (HMF) is a heat-formed contaminant and is the most noted toxin to honey bees. Currently, there are no rapid field tests that would alert beekeepers of dangerous levels of HMF in HFCS or honey.

The study (PDF) mentions that the corn syrup products are used to feed bees to start brood production in the spring, when the bees are being transported, and when nectar sources are not plentiful (such as in the fall, presumably.) Recall, though, that the bee die-offs are going on primarily in the fall and winter. So, why don't the bees dies in the spring and the summer when they're eating the stuff?

Like the other explanations, this could be just a part of the picture.