* CSI300: flat; SSEC: -0.3 pct; HSI: -1.4 pct
* Fund managers slash suggested equity, bond holdings-poll
* Sentiment in Hong Kong hit by slump in Japan stocks
SHANGHAI, April 29 (Reuters) - China stocks edged lower on Friday morning ahead of the Labour Day holiday, with investors most adopting a cautious stance amid rising bond defaults and increasing volatility in the commodities market.
Hong Kong shares dropped over 1 percent as sentiment was soured by a tumble in Japanese stocks, after the Bank of Japan disappointed markets by electing not to expand monetary stimulus on Thursday.
China's blue-chip CSI300 index dipped 0.04 percent to 3,159.46 points by lunch break, while the Shanghai Composite Index lost 0.3 percent, to 2,936.53 points.
Trading volume remained thin, while outstanding margin loans - money investors borrow to buy stocks - fell for seven days in a row, as many stayed on the sidelines.
A Reuters poll showed that Chinese fund managers cut their suggested equity exposure for a third consecutive month, to a five-month low of 69.4 percent, while advising investors to boost their cash holdings.
Reflecting growing concerns over bond defaults, the fund managers halved recommended bond weighting to 6.3 percent.
Most sectors fell, but resources shares rebounded after a sharp correction over the past sessions.
Rising volatility in China's commodity market and a government crackdown on speculation have also pared risk appetite.
China's securities regulator ordered the country's major commodity futures exchanges this week to control speculative trading activity, sources told Reuters, after a surge in prices sparked fears of a boom-and-bust cycle.
In Hong Kong, the Hang Seng index dropped 1.4 percent, to 21,099.47 points, while the Hong Kong China Enterprises Index lost 1.1 percent, to 8,957.43.
Stocks fell across the board in Hong Kong.
Banking stocks sagged after Chinese lenders posted flat profit growth amid rising bad debt.
Industrial and Commercial Bank of China Ltd (ICBC) , China's biggest lender, dipped 0.7 percent in Shanghai and was down 1.2 percent in Hong Kong.
Reporting by Samuel Shen and Pete Sweeney; Editing by Shri Navaratnam