The Philippines has raised its buying price for yellow corn by a third but the move might not be enough to prevent shortages as pricey fertilizer deters farmers from planting, the head of a farmers' group warned on Monday.

The increase was less than half the 73 percent hike sought by farmers and may not prevent further escalation in corn prices and domestic inflation if supply dwindles, said Roger Navarro, president of the Philippine Maize Federation.

"We firmly believe the only incentive we can give the farmers to plant again is to give them the price they can earn today," Navarro said.

"If this is not so, we strongly believe we will have a shortfall in corn production from the next cropping onwards."

The Philippines, which accounts for just 1 percent of world corn output, produced 3.29 million tons of the crop in the first half, slightly higher than its goal of 3.22 million tons.

The government has set a corn production target of about 7.4 million tons this year, up 9.5 percent from 2007.

Agriculture secretary Arthur Yap told reporters the state grain agency had increased its buying price for yellow corn to P10 a kilo from P7.50

The approved buying price is lower than the corn farmers' request of P13 per kilo of yellow corn, used mainly for feed, and the average market price of the grain at P11.

Assistant Agriculture Secretary Dennis Araullo reiterated that rising fertilizer costs put at risk a second-half corn production target of 4.16 million tons.

"That is critical," Araullo said. "We might not hit the target because of the high cost of fertilisers."

At least a fifth of the targeted 1.65 million hectares of corn plantations may not be planted in the next cropping season, Araullo estimated.

Yellow corn makes up nearly two-thirds of the Philippines' total corn production while the rest is white corn, used mainly for food.