New form of child labor on cotton: cultivating seedlings

Radio Liberty/Radio Free Europe's Uzbek service (Radio Ozodlik) reported a week or so ago that schoolchildren in some areas of the Fergana Valley were being sent home with paper cones and seeds and told to grow 200 seedlings in their gardens for cotton farmers to plant later in the season. Just a homework assignment, right? That initial report has been expanded into a roundup of the current state of child labor and efforts against it, available here:
http://www.rferl.org/content/Seeds_Of_Child_Labor_Lie_Deep_In_Uzbek_Cotton_Industry/1738167.html

The article makes plain the economic calculus driving the exploitation of children:  

Uzbek farmers say the answer is simple: Child labor is preferred because it's cheap. Children receive as little as $.03 for every kilogram of cotton they pick.

Ferghana-based rights activist Bahodir Elboev says the pay is so low that it cannot compare to the money adult men can earn working as seasonal laborers abroad.

"If a grown-up man works casual jobs he makes at least $6-7 a day and can earn some $200 a month," Elboev says. "Farmers never pay anyone $200 a month!"

If the state can underpay farmers rates that don't allow the hiring of wage laborers at market rates, and instead, coerce children to do the work for pennies per day, what can force them to stop, short of an all-out boycott?