If a federal agency has the power to bar a court from overturning or halting the actions of that agency—an administrative rule making body to which Congress delegates far too much power already—then that body may (and will) act with impunity. The power of such an agency would, in fact, exceed that of Congress itself.
Such a law would be worse than almost any that preceded it in this country. Under no theory of agency with which I'm familiar can one delegate more power than one has. And yet this new amendment to the GMO law appears to place some USDA powers almost entirely outside the scope of judicial review.
In effect, this amendment gives the USDA the power to ignore a federal judge’s ruling in some cases. Taking the power of judicial review out of the hand of judges.