pollenizer

/ˈpɑlənaɪzər/
noun
  1. A plant that provides pollen for the pollination of another plant, often of a different variety.
    • Apple farmers often plant a pollenizer tree nearby to ensure good fruit production.
    • This cherry variety needs a compatible pollenizer to set fruit.
    • The beekeeper placed hives near the pollenizer crops to improve yield.