Is anyone out there able to shed some light on what this might be?

if those root like extensions are on the main stem, primarily, they're called root primordia or adventitious roots and are completely normal.

If they were in contact with soil roots would form.

Carolyn

I agree with Carolyn thatÂs exactly what they are I have them on one of my yellow pear tomatoes that are on the stems 7 ft in the air. Not a thing in the world to worry about.

Worth

I HAVE WHAT LOOKS LIKE BLISTERS ON THE STEM OF MY TOMATOE PLANTS. MY PLANTS ARE IN 5 GALLON CONTAINERS AND HANGING UPSIDE DOWN. SO YOU THINK THIS IS NORMAL? THANKS, VICKIE