A new Ohio State University Extension analysis of hybrids in the 2014-15 Ohio Corn Performance Tests showed only minor variations between yields of GMO and conventional corn hybrids with the same isogenic lines.
The average yield of all traited hybrids over the two seasons was 215.8 bushels. The average of all non-GMO hybrids was 213.5 bushels. We haven’t done a statistical significance test on this, but the slight difference looks well within the range of random variation. Only 10% of the hybrids evaluated were non-GMO.
An even more comprehensive comparison would be to match hybrids from firms which market only non-GMO hybrids, and introduce new numbers as their top priority.
Ohio State Extension analysts say the reason for extracting and publishing this comparison is that many growers are looking for ways to cut seed costs and take advantage of non-GMO price premiums. The full OSU Extension report is at this link.
In general, each time a genetic structure is altered, the “debris” of deleted and displaced genes impose a metabolic drag on metabolism of a crop. That performance can possibly be made up by improved weed or pest control. That works — as long as weed and pest resistance doesn’t show up.
Some growers are finding that other means of reducing insect and weed pressure, such as cover crops, preplant or premerge herbicides and mechanical weed control, can cut total production costs while maintaining yield.