In 1981, a lawmaker strolled into India’s upper house wearing a garland of onions to protest the staple’s rising price. The vegetable necklace has been a popular protest accessory ever since.

Across India, onions are among the few ingredients used in almost every dish, alongside salt and potatoes, making them economically and politically important.

Governments can fall when crop failures, price fixing or inflation sends costs up.

Such factors contributed to the demise of Prime Minister Manmohan Singh’s government in 2014.

In this year’s election, though, low prices are the problem. Onion and potato prices have plunged along with those of other foods, and the country’s 100 million farmers are suffering. That’s a big voting sector.

Both the Bharatiya Janata Party and the Congress Party are offering farmers loan relief in the states they govern, and say they will have more solutions if they win in national elections. But some farmers aren’t interested in giving the B.J.P. and its leader, Prime Minister Narendra Modi, another chance.

In a new book about Indian voters’ moods, “Democracy on the Road,” the investor Ruchir Sharma writes: “Lately, farmers have told us they planned to vote against their incumbent government” because of “frustration over depressed crop prices.” — Alisha Haridasani Gupta

Send us feedback or questions here.

Here’s what else is happening

Britain: Prime Minister Theresa May is expected to seek another delay to Brexit from already exasperated European leaders, who meet on Wednesday. And she signaled a willingness to compromise with the Labour Party in talks over passing a departure plan, though those talks remained stalled.