Subscribe and stay up-to-date with the latest news and great offers from DEKALB, Asgrow and Deltapine.
Don't miss out on the latest agronomic news.
Local agronomic alerts.Delivered straight to your inbox.
The components of corn yield include ears per acre, kernel rows per ear, kernels per row, and kernel weight. The number of ears per acre is usually set by the V6 stage of corn growth and by V12 the number of kernel rows, kernels per ear and ear size are determined. Corn product genetics have a big influence on these yield components but environmental stress, root feeding by rootworms, nutrient deficiencies, and leaf defoliation can also have a strong effect. The potential number of kernels per row is determined around V18. Drought stress can cause a lag between pollen shed and silking at this time and may cause up to a 4% reduction in yield potential for each stress day.
Potential yield loss during grain fill can occur from stand loss, incomplete kernel set, decreased kernel weight, and premature plant death.2
Silking Stage (R1) The first 7 to 10 days are critical because cell division occurs which determines kernel number and the potential size of kernels. Severe stress can cause an average of 7% loss in yield potential for every day of stress.1
Blister Stage (R2) The developing kernels are whitish "blisters" on the cob. Severe stress can abort kernels during the pre-blister and blister stages of growth. Kernel abortion due to stress is less likely in the R3 milk stage than at the blister stage.
Dent Stage (R5) Estimated yield loss due to total plant death at full dent is about 40%, while total plant death at half-milk line would decrease yield by about 12%.4