Shares in Australia's Nufarm plunge after Monsanto weedkiller cancer finding

SYDNEY, Aug 13 (Reuters) - A Californian court finding that a Monsanto weedkiller caused a school groundskeeper's cancer has sent shares in Nufarm Ltd, an Australian maker of a similar product, tumbling 10 percent on Monday.

Monsanto, owned by Germany's Bayer AG failed to warn customers about cancer risks from glyphosate-based weedkillers, the jury in San Francisco found on Friday.

Macquarie Bank analysts estimate Nufarm earns about a fifth of its revenue from products containing glyphosate, the world's most widely-used herbicide. At one stage, its shares fell almost 17 percent in early trade.

A Nufarm spokeswoman declined immediate comment when contacted by Reuters. (Reporting by Tom Westbrook; Editing by Edwina Gibbs)