Phosphorus Fertilizer Boosts Wheat Yields in In-Furrow Applications

Wheat is a highly responsive crop to band-applied fertilizers, particularly phosphorus (P). Research at K-State has shown that in-furrow applications of phosphorus fertilizer can improve wheat yields compared to no fertilizer. In fact, yield responses were similar across P sources.

In-furrow fertilizer application involves applying phosphorus fertilizer through the drill with the seed. This method can be used either in addition to or instead of pre-plant P applications. Dry fertilizer sources with air seeders are a popular option, but other P sources, including liquid ones, are agronomically equivalent and should be chosen based on cost and adaptability.

When applying fertilizer with the seed, rates should be limited to avoid potential toxicity to the seedling. Air seeders that place the fertilizer and seed in a 1- to 2-inch band provide some margin of safety. However, adding extra N fertilizer is still a risk, especially when using products like DAP or MAP.

The N in these fertilizer products is in the ammonium-N form (NH4+), which is less likely to injure the wheat seed even in direct contact. In fact, mixing DAP or MAP with the seed can be done safely without injuring the seed or gumming up the works.