* Nikkei edges up as yen eases, dollar bounces modestly
* Longer-term bond yields rise globally, focus on BOJ
* Talk US GDP report on Friday could beat forecasts
* Alphabet shares jump to record as results impress
By Wayne Cole
SYDNEY, July 24 (Reuters) - Global bond markets were under strain on Tuesday amid talk of central bank tightening and the risk of a robust reading on U.S. economic growth later in the week, though stellar results from Alphabet could support tech stocks in Asia.
Shares in the parent of Google climbed 3.6 percent after-hours to hit a record high, valuing the internet giant at a cool $870 billion.
That made up for an otherwise dull day on Wall Street where the Dow eased 0.06 percent, while the S&P 500 gained 0.18 percent and the Nasdaq 0.28 percent.
In Asia, Japan's Nikkei bounced 0.4 percent in early trade as a pullback in the yen eased concerns about earnings pressure on exporters.
Moves elsewhere were marginal with MSCI's broadest index of Asia-Pacific shares outside Japan barely changed.
Bond bulls were still smarting from speculation that the Bank of Japan is close to announcing measures to scale back its massive monetary stimulus, a risk that lifted long-term borrowing costs globally.
Markets were worried that Japanese investors would have less incentive to hunt offshore for yield, said ANZ economist Felicity Emmett.
"The 10 basis-point steepening in the Japanese yield curve is massive in the context of a market that rarely moves more than 1" basis point, she added.
"It reflects a broader fear that central banks are reducing their purchases while U.S. bond supply is set to rise significantly."
As a result, 10-year U.S. Treasury yields jumped to their highest in five weeks around 2.96 percent and were again nearing the psychological 3 percent bulwark.
Part of the move was driven by chatter that data on second-quarter U.S. economic growth (GDP) due on Friday would easily top current forecasts of 4.1 percent.
Dealers noted some media reports President Donald Trump himself was predicting an outcome of 4.8 percent. That would not be out of bounds given the much-watched Atlanta Fed GDP tracker puts growth at an annualised 4.5 percent.
Such a strong outcome would only add to the risk of faster rate hikes from the Federal Reserve and underpin the dollar.
Against a basket of currencies, the dollar bounced to 94.619 from a low of 94.207 on Monday. The dollar also edged up to 111.40 yen, from a trough of 110.75.
The euro lapsed to $1.1690, having run into profit-taking at a peak of $1.1750 overnight.
In commodity markets, oil prices idled as the focus turned to oversupply worries and away from escalating tensions between the U.S. and Iran.
U.S. crude was flat at $67.87, while Brent dipped 7 cents to $72.99 a barrel.
Spot gold was a fraction firmer at $1,224.46.
Editing by Shri Navaratnam