Cotton Variety Response to Varying Rates of Nitrogen in Mississippi

Upland cotton responses to and utilization of fertilizer nitrogen is a function of application timing, rate, and source.  Additionally, fertilizer nitrogen effects on plant height, leaf area, boll number, and yield are well known.

An experiment was conducted at the R.R. Foil Plant Science Research Center in 2019 in Starkville, Mississippi to determine the effect of four fertilizer nitrogen rates on five NexGen cotton cultivars.  Plots measuring 12 m x 3.9 m-1 were planted with a cone planter on 21 May 2019 at 111,195 seed/ha-1 on beds spaced 97 cm-1 apart.  The test-site was comprised of a Leeper silt loam (Fine, smectitic, nonacid, thermic vertic epiaquepts) soil.  Fertilizer nitrogen rates of 0, 45, 90, & 135 kg ha-1 were applied in a single application when plants reached pinhead square to Phytogen cotton varieties: NG 5711 B3XF, NG 3729 B3XF, NG 3994 B3XF, NG 4936 B3XF & NG 3930 B3XF.