Did you know that the first 9 days of a corn plant's life will determine its yield potential?
There's theoretical genetic potential...which is the amount of production that a plant has been genetically programmed to produce, if all conditions were exactly perfect. Then there's what I'll call practical genetic potential. This is the potential that a plant has to product, given typical (less than perfect) conditions.
You may have heard citings of research that suggest that corn seed has the genetic potential to produce 1100 bu/acre. We know that our best farmers see 200-300 bu/ac depending on conditions, most of which are out of their immediate control (sunlight, water, soil nutrient availability, etc.). So, the "1100 bu/acre" would be the theoretical potential while the "200-300 bu/acre" is the practical potential.
Most farmers don't even come close to the practical potential as they are not even doing what they can control (nutrient supply) to help that plant reach its practical potential.
At the beginning of the plant's life, and given the conditions at the time, the plant makes its determination as to what it can (has the potential to) produce. If it determines two cobs, then, the potential for that plant will never be more than two cobs. If it determines 14 rows, then, the potential for the cobs will never be more than 14 rows. If its 70 kernels per row, then, the potential for the rows will never be more than 70 kernels. The plant determines all this very early and will determine based on its conditions at the time of determination.
So, as the season progresses, the plant passes through growth stages, as which time, it will INITIATE certain processes such as cob initiation, pollination, row initiation, kernel initiation, kernel fill. At each of these stages, if the conditions are not right, ...even if the potential for two cobs was determined, it may not form two cobs. That's why its very important for the plant to have the right nutrients at these critical stages of its life. At each stage, there is the chance that, if the conditions are not ideal, the plant will not initiate the given process and YEILD is LOST. Obviously, if it doesn't initiate both cobs that were determined, then you automatically lost potential for 1/2 the yield. And, of course, as you know, just because you initiate a cob, doesn't mean that the cob will fully pollinated and even if fully pollinated, doesn't mean that the kernels will be initiated. Even if the kernels are initiated, doens't mean that they will all fill.
Again, at each stage, there is the potential to lose yield, unless ideal conditions are presented. This is why the theoretical potential is never realized. Because the plant will NOT see ideal conditions at each stage and yield is inevitably lost at each stage.
You are right with your timings in that these timings refer to when the plant is initiating certain processes and, it is at these times when it is critical for the plant to have all its necessary inputs to perform the initiation to the fullest of its practical potential.
This is why I feel that the planting solution is the most influential factor in ultimate yield. Its the control point that a farmer has in the beginning to set the stage for how much potential there will be.....
Corn Hybrid has an awful lot to do with how the plant will or can react. Some hybrids are bred to only produce one cob......all you can do is support that one-cob plant with the right planting depth and spacing so as to allow for the most ideal conditions for that plant...and do all that you can do to make that one cob the most it can be. longer and thicker for more rows and more kernels.....more mass.