CATCo Share News (CAT)

* Futures down: Dow 1.9 pct, S&P 1.32 pct, Nasdaq 1.6 pct

* S&P 500 set to open below its 200-day moving avg

* Boeing tumbles 4 pct; Caterpillar down 3 pct

* Ford, GM, Tesla, Fiat sink 2 pct to 4 pct

* Chipmakers hit, led by AMD's 4 pct decline(Updates prices)

By Sruthi Shankar

April 4 (Reuters) - Big U.S. manufacturers, grain merchantsand chipmakers were the early casualties on Wednesday afterChina and the United States announced tariffs on $50 billion ofeach others' imports, cementing fears they were moving toward atrade war.

The speed with which the trade spat between Washington andBeijing is ratcheting up – the Chinese government took less than11 hours to respond with its own measures – led to a sharpsell-off in global stock markets and commodities.

At 8:57 a.m. ET, Dow e-minis were down 459 points,or 1.91 percent. S&P 500 e-minis fell 34.5 points, or1.32 percent and Nasdaq 100 e-minis declined 103.5points, or 1.6 percent.

The declines were broad based. All 30 Dow Jones IndustrialAverage components were lower in premarket trading. About268 of the S&P 500 components were lower. Only two of themost active U.S. stocks premarket were higher.

"It's tit-for-tat as China retaliates, sending the marketsin a tailspin. Today's decline will likely accelerate the paceof testing the indices yearly lows in the coming days," saidPeter Cardillo, chief market economist at First StandardFinancial in New York.

The stock futures implied the S&P 500 would not only openbelow its 200-day moving average, a key support level watched bytechnical analysts, but also challenge its 2018 low from Feb. 9.

China levied 25 percent additional tariffs on U.S. goodsearlier in the day. But unlike Washington's list that coversmany obscure industrial items, Beijing's covers 106 key U.S.imports including soybeans, planes, cars, and chemicals.

As has been the case since the trade war fears surfaced,industrials were the worst hit. Shares of Boeing, thesingle largest U.S. exporter to China, tumbled 4.6 percent.Caterpillar fell 3.5 percent.

Automakers Ford, General Motors, Fiat Chryslerand Tesla fell between 2 percent and 4percent.

Grain merchant Archer Daniels was down 2.8 percent,while Bunge slipped 2.5 percent.

Chipmakers, many of which have the highest revenue exposureto China among S&P 500 companies, also fell. All components ofthe Philadelphia chipmakers index trading premarket werelower, led by AMD's 4 percent drop.

"As a sector, technology has the most to lose from a worldin which global trade is restricted and of course, some of thesubjects of the tariffs, will also be hit," said Rick Meckler,president of investment firm LibertyView Capital Management inJersey City, New Jersey.

Investors headed for safer bets. U.S. 10-year Treasury yieldwas last down 2.75 basis points at 2.76 percent,while gold prices went up more than 1 percent.(Reporting by Sruthi Shankar in Bengaluru; Editing by SavioD'Souza)