NEW YORK (TheStreet) -- The world's eyes are yet again on Ukraine, as fighting in eastern provinces intensifies and Russian and U.S. military forces stare each other down in the Black Sea.

So what is an investor to do? Start by forgetting Ukraine's natural gas pipeline to Europe: The effects of the conflict will more likely play out in the world grain markets.

First, the gas worries, which may be little more than hot air. Yes, the European Union does import a lot of gas from Russia, but less than previously. At year-end the total was around 9 billion cubic feet a day down from close to 14 billion at the beginning of 2011, according to estimates from the Energy Policy Research Foundation.

On top of that the fighting won't likely impact the pipelines because they aren't in the same region of the country, says Max Pyziur, senior advisor at the foundation.

"As for whether Russia will turn off the gas, I don't think it can afford to at the moment," says Dr. Tracey German, Russian expert at the Defence Studies Department of Kings College London. "It needs to maintain regular sources of income."

Of course, none of that means that Russia will cease its belligerence, just that the gas won't be turned off anytime soon.

The real action is much more likely to play out in the corn and wheat markets, where prices may rally globally if the country suffers a continued currency crisis. Here's how it works.

Ukraine is a major player in the global export market for these grains. When farmers are concerned that the local currency is going to drop significantly they can, and do, hold back from exporting their grain as a hedge against the devaluation

In January 2014, the dollar would buy you 8.1 Ukrainian hryvnia; currently you'd get around 21.

Those Ukraine farmers that did hold back wheat or corn would have made out like bandits on a payment in U.S. dollars.

"That's a rational economic response if you are a producer," says Jerry Norton, grains analyst for USDA's World Agriculture Outlook board. "If they have another devaluation in currency, you would assume they'd do that again."

Ukraine's farmers have a lot of grain to hold off the market. A lot. Ukraine is projected to be the world's third-largest exporter of corn and the sixth-largest of wheat, according to projections from the USDA. The projections are for 16 million metric tons of corn and 10.5 million tons of wheat for the 2015-2016 season.

It doesn't matter that other countries might be bigger producers of these grains. What determines the global price is the export market. (Remember, markets are made at the margin.)

So if Ukraine's farmers keep hold of their stockpiles, we'd likely see a rally in wheat and corn prices, assuming other things remain the same.

If the fighting continues to intensify through the summer, then it seems probable that investors will lose confidence in the hryvnia, leading to further declines. Ukraine's farmers must be only too aware of the situation, and my bet is they are getting ready to stockpile grain, if necessary.

Who will benefit from any such corn and wheat rally other than the farmers? Commodities futures traders, of course, along with makers of plant nutrients such as Potash Corp. of Saskatchewan (POT) and Mosaic  (MOS - Get Report) as well as agricultural firm Monsanto (MON), which makes Roundup weed killer and engineered seeds.

In addition, investors might want to take a look at the Market Vectors Agribusiness ETF  (MOO - Get Report), which holds both Monsanto and Mosaic as well as other farm-related stocks. Generally, agricultural companies can charge more for their products when the price of crops is robust.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.