Russia and Ukraine are two of the world’s biggest exporters of chickpeas — Russia alone accounts for roughly a quarter of the global chickpea trade — and the supply of the legume may be reduced by as much as 20 percent this year, according to an estimate by the Global Pulse Confederation.

The fighting in Ukraine as well as the economic sanctions levied against Russia are the biggest disrupters of the flow of chickpeas, according to the industry group, which represents growers and traders of pulses, the dried seeds of legumes including peas, beans and lentils. Rising freight prices, which have been driven in part by higher oil costs, are another problem.

“Globally, chickpea prices may rise by 15 to 20 percent — the same value as the fall of the supply,” said Navneet Singh Chhabra, an analyst at the trade association and the director of Shree Sheela International, a global chickpea trader.

Russia is one of the world’s biggest suppliers of chickpeas, producing about 250,000 tons of chickpeas a year. But economic sanctions are limiting the ways its growers can get chickpeas out of the country, Mr. Chhabra said.

The problem is different in Ukraine: Much of its crop is usually planted in Kharkiv Province, where fighting has hampered planting. Ukraine usually produces between 30,000 and 50,000 tons of chickpeas a year, but will produce a maximum of 5,000 tons this year, Mr. Chhabra estimated.

Russia is an important supplier of a smaller variety, called Kabuli chickpeas, that is particularly preferred for hummus, Mr. Chhabra said.

Russia’s biggest export markets are Iraq, Jordan, Egypt, Pakistan and India, and demand from those markets will cause ripples around the world, he said.

“The South Asian market will buy whichever chickpea is cheaper, but in the Middle East and in the U.S., there is a strong preference for the smaller, smoother Kabuli chickpea, because that is what makes the best, wrinkle-free hummus,” Mr. Chhabra said. “And Russia exports the best and the biggest amount of Kabuli chickpeas to the world.”