Tokyo stocks touch 4-wk low as Wall St, dollar fall

(Updates to midafternoon)

TOKYO, Oct 22 (Reuters) - Japan's Nikkei average tumbled 3.2 percent on Monday to a four-week low, battered by a strong yen and a slide on Wall Street that set off broad selling of exporters such as Hitachi Ltd (6502.T). High-tech shares were also hit by the slide, which saw both the Nikkei .N225 and the broader TOPIX index hit one-month lows soon after the opening, mainly on last week's Wall Street plunge on growing fears about the U.S. economy. "The Tokyo market lacks strong, independent factors until later this week, when the autumn earnings season moves into higher gear, so the vast majority of its moves today are in response to what happened on Wall Street," said Masayoshi Okamoto, head of dealing at Jujiya Securities. "There also may be a bit more of an impact from other Asian markets, particularly as we move into the afternoon and India comes in."

The dollar, which at one point fell more than 1 percent to 113.25 yen JPY=, hitting a six-week low, recovered to the 114 yen level by midafternoon, at which point stocks had also erased some of their earlier losses.

But traders said the rise in stocks was due more to short-term trading than any significant buying factor, with participants starting to turn their eyes to later this week, when Honda Motor Co (7267.T), Sony Corp (6758.T) and Nintendo Co Ltd (7974.OS) are scheduled to announce results.

"The Japanese market will finally get some independent trading energy then. Until that point, we're likely to mostly track overseas markets due to the fact that the market gains most of its energy from international investors," Okamoto said.

U.S. stocks had their biggest fall in more than two months on Friday, with the Dow Jones industrial average .DJI losing 2.6 percent after Caterpillar Inc (CAT.N) said several industries it serves are in recession, suggesting the housing sector slump is infecting the wider economy.

The Nikkei was down 2.6 percent or 432.22 points at 16,382.15 as of 0429 GMT. The TOPIX was down 2.1 percent at 1,557.05. Selling centred on exporters, with Sony down 1.8 percent at 5,220 yen and Hitachi down 2.4 percent at 731 yen. Car companies were also hit, with Honda down 2.4 percent at 3,740 yen.

Nintendo was down 3. percent at 64,100 yen.

Trading firms, which did well last week, also slid. Itochu Corp (8001.T) was down by 5.5 percent at 1,365 yen and Marubeni Corp (8002.T) lost 5.2 percent to 974 yen.