|
| Jim,
The reason I say it looks like chilling injury is that in the pics labelled 'scan0001' and 0002 (in original post at 03:59 server time), the roots are very distorted -- wrapped quite tightly around each other (and wrapped/distorted directly from their source inside the kernel in 0001), and abnormally truncated. Essentially the only other thing that causes distortions such as these is herbicide injury, which you have ruled out.
In the seedling that is sliced open, there is brown tissue inside the lowermost part of the shoot inside the kernel, which is due to disease invasion (a secondary problem that goes along with chilling injury). Chilling injury usually doesn't kill the tissue outright, but instead weakens it sufficiently for it to succumb to invasion by pathogens. This is likely what occurred to the kernel in 'scan0001' in your post at 20:24 -- the radicle [first root] was injured and became infected and died, although the secondary roots survived and look normal. (Incidentally, the coleoptile [shoot] is going the same direction as the secondary roots, a result of the 'confusion' created by the lateral slit of the cross-slot opener.)
Apparently the seed lot was low vigor, which greatly increases the susceptibility to outcomes such as these.
Fertilizer damage would look different -- there wouldn't be abnormalities (or very few), but there would be kernels that died soon after exserting a radicle or coleoptile, or before any sprout is visible. In a few cases, depending on how and where the fertilizer was applied, along with certain weather conditions, the seeds will germinate okay but will have some root die-back from fertilizer toxicity -- but there will be a distinct pattern (the roots only die back on the side where the fertilizer was located), and without any growth abnormalities. | |
|
Corn Germination problems
