Dark parches with bumps on stem

https://www.gardeningknowhow.com/edible/vegetables/tomato/white-growths-on-tomato-plants.htm i'd wager it;s similar to this. Are they hard little bumps? if tehy don't easily rub off (compared to adventitious roots), i'd wager it's not fungal or microbial cuases and moe likely just a little oddity in the plant... maybe high RH in these faily dark areas? any condensation at night? dark and moisture will cause roots to form... even if above ground. if it is clearly superfical and growig on the plant vs growing out of it, then take some h2o2 and rub it off. 3%, undiluted. satuate area.. might discolor it a bit but it will not kill the plant or limb. if they are hard nodules, i'd ignore them, though. fungus creates a mycelium network below surface.. so cleaning surface does not "clean" the plant of fungus. it's still there. you just can't see the parts that remain. this is why bud washing WPM-infected buds doesn't do what ppl think... bud washing can clear off stuff from surface, but will not rid the plant of an infection that involveds anything below the surface.