When repotting my one. sick plant, I noticed that many of the roots looked dead and darkened. I stripped the sheaths off and found that the fine root fibers looked healthy enough. So I did this with all the dead sheaths and left the inner root. Was this a correct procedure?
That “strand” in the middle is the vascular bundle.
If there is viable, living tissue at the end, it will continue to grow and function - at least for a while. That bundle is pretty durable, but it has less ability to fend off pathogens than does a fully functioning root - but less tissue to be vulnerable, as well.
If the bundle is all that is left, it will function primarily as a mechanical stabilizer, as it’s ability to absorb water is limited, as well.