On its conference call Monday, McDonald's (NYSE: MCD) announced it will be creating its own plant-based burger, the McPlant.

McDonald said some markets will be testing the burger next year.

Beyond Meat (NASDAQ: BYND), which has partnered with McDonald's in some markets and was expected to get a wide-U.S. partnership deal, is under heavy pressure on the news. Beyond Meat shares fell 5% before being halted on volatility as the news broke.