Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/9/2017
Publication Date: 7/12/2017
Citation: Lin, Y., Watts, D.B., Way, T.R. 2017. Poultry litter placement effects on cotton seedling emergence and early growth stage. Agronomy Journal. 109:1678-1686.
Interpretive Summary: Applying poultry litter (PL) to the soil surface may degrade water quality. Recently, a prototype implement for applying PL in bands below the soil surface was developed to minimize the influence of litter on water quality degradation. It is unclear if planting cotton in or near the PL bands will negatively or positively influence seed germination and seedling growth. This information is needed for recommending to producers the lateral distance required to minimize seedling damage when subsurface banding PL next to planted crops rows. Thus, a study was conducted to evaluate poultry litter band placement. Placing cotton seeds 5 cm to the side of subsurface PL bands resulted in seed germination rates and early stage plant growth similar to that of surface applied PL (standard practice). In contrast, placing subsurface PL bands below the seed or seeding directly in bands dramatically reduced cotton seed germination and inhibited early stage plant growth and root system establishment.
Technical Abstract: Interest in using poultry litter (PL) as a nutrient source for row crop production has increased in the Southeastern U.S. Poultry litter is generally broadcasted on the soil surface. This practice exposes litter N to volatilization and litter P to loss with surface water runoff, which potentially negatively impacts the environment. Placing PL in narrow bands below the soil surface has been shown to reduce such losses and improve crop yield, but the influence of band placement on seed germination and seedling growth is not well understood. Thus, a glasshouse experiment was conducted with a Marvyn loamy sand to determine the effects of PL placement on emergence and early stage growth of cotton (Gossypium hirsutum L.). Poultry litter placement was compared with ammonium sulfate (AS); both were applied at a rate of 112 kg N ha-1. The PL and AS treatments consisted of surface broadcasting, banding 5 cm below or to the side of seed, seeding directly in bands, and an unfertilized control. Banding 5 cm to the side of seeds produced similar seed germination ratios, plant biomass, leaf area, leaf chlorophyll content, and root morphological parameters to that of the control and surface broadcast treatments for cotton fertilized with AS and PL. However, seeds placed directly in PL or AS bands showed the lowest seed germination ratio and growth parameters. Therefore, banding PL 5 cm or more to the side of seeds may be an effective fertilizer management strategy for cotton production, however, sowing directly into PL bands can inhibit germination and early growth of cotton.