Chemical maker DuPont reported a 59 percent fall in quarterly earnings, cut its full year 2009 earnings forecast due to weak demand, and said it will undertake additional cost cutting measures.

First-quarter net income fell to $488.0 million, or 54 cents a share, compared with $1.19 billion, or $1.31 a share, last year. Sales fell 20 percent to $6.87 billion.

Analysts, on average, forecast earnings of 52 cents a share, before items, on revenue of $7.44 billion, according to Reuters Estimates.

For full-year 2009, the company expects earnings to be between $1.70 to $2.10 a share, down from its earlier forecast of earnings to be in the range of $2.00 to $2.50 a share.

The revision anticipates that weak demand across key markets will continue throughout 2009, the company said in a statement.

Analysts, on average, were expecting full-year 2009 earnings to be $1.88 a share.

DuPont shares, which rose 13 percent in the last three months, closed at $26.74 Monday on the New York Stock Exchange. In the last 52 weeks, the stock has traded in the range of $16.06 to $52.34.

(Reporting by Hezron Selvi; Editing by Derek Caney)