Shares in Monsanto hit a four-year top after the seed giant, boosted by strong seed sales in Latin America and the US, trounced Wall Street expectations for quarterly profits and raised expectations for the full-year.

The US-based group, the world's biggest seed company, unveiled earnings for the September-to-November period of $339m – a rise of 169%.

On a per-share basis, Monsanto's earnings, on an ongoing basis, equated to $0.62, well ahead of the $0.37-a-share result that analysts had expected

And the group said that the "strong results" were prompting it to raise to $4.30-4.40 a share its guidance for the full year, to the end of the August, from a previous target of $4.18-4.32 per share.

Brazil dispute

The guidance excludes a potential hit of $0.20-0.25 per share relating to a legal dispute in Brazil, where Monsanto is embroiled in a legal dispute with customers over patents on its soybean seeds.

Monsanto from mid-October to last month suspended royalty payments from Roundup Ready soybean seed, genetically modified to tolerate glyphosate weedkillers such as the group's Roundup brand.

Nonetheless, the statement was well received by investors, who sent Monsanto shares to $99.99 in morning deals in New York, their highest since September 2008.

The shares closed up 2.6% at $98.50.

'Strong demand'

Monsanto attributed its profits rise, on revenues up 21% at $2.94bn, in particular to sales of corn seed, which soared 27% to $1.14bn.

In both Brazil and Argentina - South America's top two corn-growing countries, where plantings are just about wrapped up - "the company is achieving strong demand for its corn products", boosted by a trading up by growers to higher-specification GM seed.

The group's Genuity VT Triple Pro seed, modified for resistance against corn earworms and army worms besides glyphosate tolerance, "is on track to be 40% of the company's Argentine corn portfolio in just its second year on the market", Monsanto said.

Corn seed squeeze?

However, the group also flagged "strong early momentum" in US corn seed, ahead of sowings in the spring, "with the order pace ahead of the same point in time last year".

The strong start reflected an "open fall", and early 2012 harvest, which meant that, among farmers, "there was a lot of focus on securing their first hit on seed".

Market talk has suggested there may be a shortage of US corn seed for this year, because of the shortfall in the 2012 harvest.

"We feel very good about our ability to supply against the market," Hugh Grant, the Monsanto chairman and chief executive, said.

He restated a forecast of US corn seedings of 96m acres, a historically strong number, if below last year's 96.9m-acre figure, and some talk among consultancies such as Informa Economics of a figure close to 100m acres.

Safra vs safrinha

Monsanto also forecast that, for a second season, Brazil would see strong sowings of safrinha corn in, which is planted on ground vacated by the newly-started soybean harvest.

Mr Grant told investors: "As we expected, the initial corn acres in Brazil's summer season were lower than last year," with farmers choosing largely to plant soybeans instead.

"But the market is set for one of the largest-ever second-season, safrinha crops, keeping total [corn] acres on a par with last year."

There is some expectation that Brazil's safrinha crop, meaning little crop, may exceed what has historically been the main harvest.