COMMODITIES-Spain plan lifts markets; gold eyes best quarter in 2 yrs

* Stimulus efforts, supply risks lift commodities in Q3

* Brent on track for best quarter since Q1 2011

* Wheat gains most in quarter since 2010

* Copper set for 2nd best month this year

By Manolo Serapio Jr

SINGAPORE, Sept 28 (Reuters) - Commodities rose on Friday, spurred by optimism over budget reforms in debt-laden Spain and hopes China will take more steps to boost its economy, with gold set to post its best quarter in years and oil its biggest such gain in more than a year.

Bond-buying efforts by central banks from the United States to Europe to bolster a fragile global economy had boosted raw material prices over the past three months, lifting oil, gold and copper to multi-month highs.

Corn and soybeans were also on course to end the quarter with big gains, although prices have come off record highs hit in August and September as harvest pressure took over supply worries fueled by a massive drought in top exporter the United States. Wheat is headed for its best quarter since 2010 on expectations of export curbs by major shipper Russia.

Spain's detailed timetable for economic reforms and a tough 2013 budget peppered with spending cuts drove both commodities and equities higher on Friday, although analysts were unsure if the upward momentum will be sustained.

"The euro zone crisis may have overcome one hurdle -- Spain -- but the overall situation is far from having a long-term solution," said Victor Shum, managing director for downstream energy consulting at IHS Purvin & Gertz.

"The U.S. is still sluggish and we have weak news out of China. The economic picture is far from robust. If I look at the economic picture, the immediate outlook is bearish."

Recent U.S. economic data from has pointed to an uneven recovery and China, a major consumer of oil and base metals, has seen its vast manufacturing sector shrink for an 11th month in a row in September.

Brent crude gained 57 cents to $112.58 a barrel by 0708 GMT, heading for a modest decline on the month. But for the quarter, the benchmark is up 15 percent, its biggest gain since January-March 2011, also aided by supply disruption risks given ongoing tensions between Iran and the West.

U.S. crude rose 55 cents to $92.40 a barrel, and is up 8.8 percent for the quarter.

GOLD SHINES

Spot gold rose 0.2 percent to $1,780.36 an ounce, on course for a sixth straight weekly rise -- its longest streak of weekly gains in more than a year. The prices are also set for their strongest monthly rise since January.

For the quarter, bullion is up over 11 percent, its best performance since April-June 2010, as stimulus efforts burnished the precious metal's appeal as a hedge against inflation.

"There is definitely no reason for gold to go back to $1,500 level," said Yuichi Ikemizu, head of commodity trading, Japan, Standard Bank.

"I don't see gold going on a spectacular rally right now, but towards the end of year it is likely to hit $1,900 level."

Copper climbed 1 percent to $8,257.25 a tonne, and has risen 8.4 percent for the month, its second best monthly showing this year.

Hopes are high China, which consumes about 40 percent of the world's refined copper, would launch more measures to hasten economic growth that is likely to slow this year to below 8 percent, a level unseen since 1999.

China goes on a week-long holiday next week, but an adviser to the country's central bank said Beijing has severely underestimated this year's global economic slowdown and further cuts to Chinese interest rates or bank reserve requirements hinge on any new deterioration in the external environment.

In the grains market, Chicago soybeans rose 0.8 percent to $15.82-3/4 a bushel and corn steadied ahead of the U.S. government's quarterly stocks report.

Corn and soybeans are looking at their worst month in a year, each with a loss of around 10 percent, as a record harvest pace pushed back prices which a drought had lifted to all-time highs in August and September.

Wheat rose 0.2 percent to $8.57-1/2 a bushel, with the December contract up more than 10 percent for the quarter, its biggest three-month jump since the last quarter of 2010. (Editing by Himani Sarkar) (manolo.serapio@thomsonreuters.com; +65 6870 3884; Reuters Messaging: manolo.serapio.reuters.com@reuters.net)