UPDATE 2-Judge throws out Dole "bananeros" cases, citing fraud

* Decision casts doubt on $2 bln in judgments in other cases

* "Pervasive consipracy" behind two pesticide lawsuits- judge

* Judge says scheme reached Nicaraguan judiciary (Adds byline, details from hearing, background)

By Gina Keating

LOS ANGELES, April 23 (Reuters) - A California judge on Thursday threw out two pesticide lawsuits against Dole Food Co and other companies by plaintiffs claiming to be banana farm workers, citing a "pervasive conspiracy" by plaintiffs' attorneys and Nicaraguan judges.

The ruling by Los Angeles Superior Court Judge Victoria Chaney puts in doubt $2 billion in pending judgments in dozens of similar lawsuits. Chaney also said she would refer the matter to states' bar associations and to prosecutorial agencies.

The plantiffs, known as bananeros, have won judgments against Dole in Nicaraguan courts after claiming they were made sterile by the chemical DBCP, which was banned in the United States but was used by Dole to control fungus. The other defendants were Dow Chemical (DOW.N) and AMVAC.

Privately-owned Dole, is the world's largest producer of fruits and vegetables.

Chaney made the ruling after a three-day hearing on fraud allegations that cropped up during the first of about 40 toxic tort lawsuits to be tried in her court involving thousands of plaintiffs from Costa Rica, Guatemala, Panama, Honduras and the Ivory Coast .