July 23, 2013

​What Happens After Pollination?​​


What happens after pollination and how long it takes before the crop is “made” are great questions. The answer can change from year-to-year.

Once the corn has pollinated, the fourth component of yield takes effect which is the grain fill period. During this period, the key is to convert as much sugar as possible into starch. Depending on the weather within two weeks after pollination, the corn plant will determine how many kernels it can support. If stress occurs during this timeframe, the corn plant will abort kernels to adjust for the number of kernels it can support. The process of grain fill usually takes about 55-65 days. This period can be shorter or longer depending upon the conditions the plant is going through. The longer the grain fill period, the deeper the kernels (Figure 1) and the higher the potential yields. WhatHappensAfterPollinationImage2.jpg

The best scenario for grain fill is to have warm days (mid 80s) and cool nights (mid 60s to lower 70s), which reduces respiration rate and GDU accumulation. Hot, dry days and very warm nights will push the grain fill period too fast and shorter kernel depth will result. The plant cannot respire and keep up with the demands of the kernels. 

Corn Kernels dent about 35-45 days after pollination when moisture content levels are around 55%. Grain fill continues until the maturity line on the kernel is fully down to the kernel tip and black layer occurs (Figure 2).​​​​

By: Jim Erwin |