Yield Response of Corn Products to Seeding Rate - Storm Lake, IA
Several years of research have indicated that corn yield has a positive correlation with plant population until a threshold is reached, beyond which, yield decreases. Defining this threshold for each corn product is difficult as it is highly influenced by several factors including management practices and the environmental conditions during the growing season.
Knowing the threshold is critical as it forms the basis upon which other management practices, such as nitrogen rate, are based.
The objective of this study was to determine the yield response of corn products at different seeding rates to find the optimum seeding rate.
Research Site Details
Four corn products were planted at 33,000 (33K), 38,000 (38K), and 43,000 (43K) seeds/acre.
The trial was carried out in 20-inch row spacing, with six rows in 100-ft-long plots with two replications. he trial was carried out in 20-inch row spacing, with six rows in 100-ft-long plots with two replications.
A total fertilizer application consisted of 167-57-93-14-1 (N-P-K-S-Zn) in which 150 lb of 32% UAN was applied in the spring.
Weed management consisted of an early post-emergence program. • No fungicide or insecticide was applied.
Understanding the Results
In all four products, 38K seeds/acre was the optimum seeding rate.
207-27STXRIB brand blend was the highest yielding product at all seeding rates.
Across all products, there was a minimal yield difference between the 33K and 43K seeds/acre seeding rates.
What Does This Mean for Your Farm?
We consider a 6.25 bu/acre response in a 5K seeds/acre increment to be economical.
Each corn product showed an economical response to increasing the seeding rate from 33K to 38K seeds/acre.
No corn products showcased value in increasing the seeding rate beyond 38K seeds/acre.
Standability was quite good and no harvestability problems were encountered in the whole trial.