This summer will be my 4th year growing corn for my research. Every year, I’ve seen some crazy things in the transgenic and non-transgenic fields alike. For example:
On the left is “tassel ear”, where silks and kernels (female, seed producing plant parts) appear on the tassel (male, pollen producing plant parts), where they are most certainly NOT supposed to be – it’s ok for sorghum and other grasses, but not for corn! On the right, there are at least 2 ears where there should be one, and those leaves poking out between the two might be more ears. Neither of these plants are transgenic or carry heritable mutations that cause these strange phenotypes. Both transgenic and non-transgenic fields are treated with a herbicide before we plant but after that the plants are grown with no additives, chemical or otherwise.
So, what the heck is going on?
I’ve always meant to look it up, but pollination season is so busy, and then it’s harvest season which is so busy, and then we’re analyzing the seeds… you get the idea.
While looking for pictures of corn borer damage, I found an awesome site by Peter Thomison and Allen Geyer of the Horticulture and Crop Science Department of Ohio State University: Troubleshooting Abnormal Corn Ears and Related Disorders (pdf, also available in Spanish).
They say that tassel ear is due to a variety of causes, including mechanical injury due to hail, which we did have pretty badly last year. No one really knows what causes “bouquet ear” with multiple ears appearing where there should be one, but it might be due to temperature stress due to cold.
There are many other common but strange corn phenotypes explained on their site. Check it out!