Tillage Effects on Corn Response to Starter Fertilizer

Abstract

Tillage selection has been identified as a factor that may influence corn response to starter fertilizer. The objective of this experiment was to determine if tillage practices affect corn growth and grain yield response to starter fertilizer. The experiment was conducted near Columbia, MO in 2000 and 2001. The experimental design included three hybrids, with and without tillage and with and without starter fertilizer (30 lb N/acre and 13 lb P/acre), placed 2 inches to the side and 2 inches below the seed. Tillage treatment by starter fertilizer interactions were not significant except for plant height measured eight weeks after planting in 2001. Tillage did not affect corn response to starter fertilizer. No‐tillage plots were 5.7 and 3.5 inches taller at 6 weeks after planting than tilled plots in 2000 and 2001. At 8 weeks after planting no‐tillage plots were 7.5 and 6.0 inches taller than tilled plots in 2000 and 2001. No‐tillage plots reached silking 2.3 and 1.6 days earlier in 2000 and 2001 than tilled plots. Starter fertilizer also affected plant height and silking date, but to a lesser extent than tillage. The effects of starter fertilizer on plant height and crop development never translated into an effect on grain yield. We found no evidence that growers who use no‐tillage are more likely to see yield responses from starter fertilizer than growers who use some other form of tillage.

Hybrid and Planting Date Effects on Corn Response to Starter Fertilizer

“…Averaged across all hybrids, plant heights of plots treated with starter fertilizer measured six weeks after planting were greater than plant heights of plots without starter fertilizer for all planting dates except 17 May 2001 (Table 1). Our results are similar to results from many other studies that have reported starter fertilizer increased corn plant height or weight during vegetative growth stages (2,3,5,6,7,8,10).…”

“…Previous studies have concluded that starter fertilizer often reduces the number of days required for silks to emerge (7,8,12). In our study, the number of days from planting to midsilk was reduced by starter fertilizer in both years at all planting dates (Table 4).…”

Pre‐Plant and In‐Season Nitrogen Combinations for the Northern Corn Belt

“…Corn response to 5×5 starter may also depend on the interaction between growing season length and hybrid maturity class. On Missouri silt-loam soils, increased early corn growth and reduced days to silking were attributed to hybrid maturity class, tillage, and 5×5 starter application but grain yield was not affected (Cromley et al, 2003(Cromley et al, , 2006. Bundy and Andraski (1999) observed that a positive yield and economic response to 5×5 starter was positively correlated (R 2 = 0.51) to the sum of hybrid relative maturity (RM) and planting date in Julian days (PD) and most likely when RM + PD > 235.…”