The Reuters-Jefferies CRB index, a measure of 19 commodities, was on course for a 6 percent rise in the quarter, as unrest in the Middle East underpinned energy markets and outweighed the impact of Japan's worst crisis since World War II and monetary policy tightening in China.

Brent crude for May advanced 87 cents on Thursday to $116 a barrel by 0626 GMT, less than $4 off a 2-1/2-year high near $120 on Feb. 24, and up 23 percent so far this year. Brent plunged to below $108 in the aftermath of Japan's earthquake before recovering.

U.S. crude climbed 61 cents to $104.88, heading for a rise of 15 percent on the quarter and the outlook remained bullish.

"The world economy should be quite positive, especially after mid-May, and the downside for crude should be quite limited because of the geopolitical risk of disruption to supply in the Middle East and North Africa," said Tetsu Emori, a Tokyo-based commodities fund manager at Astmax Investments, adding that he expected U.S. crude to end the year close to $120.

Threats to supply helped cotton to an eighth consecutive quarterly gain, on course for a jump of around 35 percent, after nearly doubling in price during 2010.

But a U.S. government report detailing planting of various crops could unravel the fibre's place as a top performer.

A Thomson Reuters survey showed U.S. cotton sowings are expected to reach a 5-year high of around 13.21 million to 13.24 million acres, up almost 20 percent from the 11.04 million acres planted in 2010.

Global economic growth combined with geopolitical risk could continue to benefit silver, which vaulted 22 percent in the first quarter.

"Silver's seen a perfect storm with a combination of a positive economic outlook to boost its industrial demand, together with inflation risks, geopolitical unrest and natural disasters. Little wonder it jumped so much," said a Singapore-based bullion trader.

"The supply of physical silver is also fairly tight. The ETFs are sucking in metal, and although we have come very far, very fast, silver looks like it has a lot of staying power with $40 an ounce looking likely."

By 0752 GMT, spot silver rose 0.6 percent to $37.68.

Gold also inched up on Thursday and was on track for its 10th consecutive quarterly rise since 2008.

Gold touched a record $1,447.40 last week. It has since retreated to $1,428,90, but is on track for a rise of 0.7 percent for the quarter. "I think sentiment is slightly bullish because there are still many uncertainties around. Even though the euro zone is expected to increase interest rates, it will only be a small increase," said Ronald Leung, director of Lee Cheong Gold Dealers in Hong Kong.

U.S. wheat, corn and soybean futures were almost flat as traders stayed on the sidelines ahead of a U.S. Department of Agriculture report on planting intentions due later in the day.

Chicago Board of Trade May wheat fell 0.31 percent to $7.25 a bushel by 0341 GMT. CBOT May corn was unchanged at $6.63-1/4 a bushel while May soybeans lost 0.05 percent to $13.71-1/4 a bushel.

"Tonight's USDA planting intentions report and evolving crop weather will be the primary focus of the market for the next few sessions," Commonwealth Bank of Australia said in a note.

For the quarter, corn prices have risen 5.5 percent, but soy and wheat both fell, down 1.4 percent and 8.5 percent respectively.

In base metals, tin and aluminium were the strongest performers in the first quarter with rises of 16 and 6 percent on the final day of the month, leaving copper flagging with a loss of 1.7 percent, even though it hit a record high in February.

Three-month copper on the London Metal Exchange rose 0.6 percent to $9,438.50 a tonne by 0702 GMT, but was 7 percent off the record high of $10,190 struck in February.

The most-active copper futures contract on the Shanghai. Futures Exchange fell 0.8 percent to 70,700 yuan.

Attention is on Friday's U.S. non-farm payrolls report. Investors have geared up for a robust number, after a report by ADP showed U.S. private employers added 201,000 jobs in March.

But if the data disappoint, the second quarter could start with a thud.

"The market has written off this quarter as a draw. There is not much to do other than watch the clock tick down and hope nothing else happens," said a Singapore-based trader.

"I don't expect the new month to start much differently. The jobs report casts a huge shadow and while we are under that, few investors will want to take a big punt."