URUAPAN, Mexico, (Reuters) – This sunkissed corner of  western Mexico is the source of an annual bounty of guacamole  dip for U.S. Super Bowl fans, but extortion and kidnapping by  drug gangs has cast a grim shadow over its avocado farmers.

The drug lords of Michoacan state have branched out in  recent years from trafficking narcotics to menacing the  prosperous avocado barons whose produce will be gobbled up by  millions of Americans during Sunday’s football championship.

Michoacan’s avocado farmers can easily earn more than  $150,000 a year, a huge sum in Mexico.

All the large growers and packers around the city of  Uruapan have been threatened, people in the industry say, as  well-armed cartels search for new sources of revenue amid  pressure from a government crackdown.

Locked in a ruthless war with rival smugglers and security  forces, Mexico’s drug gangs have slain some 18,000 people since  late 2006. They are equally ruthless with business owners and  farmers who are targeted for extortion money or ransom. “In the last two or three years it has gotten worse,” a  leader of the local avocado industry said, asking not to have  his name printed. “It’s not something we like to talk about.  It’s just something we live with.”

With demands for regular payments, the cartels suck cash  out of an industry that has brought hundreds of millions of  dollars to Michoacan over the last decade. Kidnap ransoms are  often equivalent to hundreds of thousands of dollars.

Many growers now stay clear of their prized land, managing  their farms remotely, for fear of being approached or abducted.  Some go to farms during the day with bodyguards but live with  their families in towns a safe distance away.

“Many of them give money, others don’t,” one manager said,  also declining to be quoted by name. “If you don’t give it,  well, you are putting yourself in danger.”

In early November, avocado producer Martin Gallardo, 62,  was snatched by three armed kidnappers. Although his family  agreed to pay a ransom, he was found dead two weeks later.

Police arrested several men in connection with that murder  and the kidnapping of three other businessmen, one of whom was  chained to a tree and shot after his family had paid a ransom.