Solanum lycopersicum 'Brandywine Pink'

My bf planted our tomatoes in smaller pots this yr ( did with what we had) over fed them which burnt the leaves & roots but it retook & wondering if whats seen on the stem is new exposed roots? Thought aphids at 1st.

yes new roots. i plant in a 4" deep trench leaving only top out. the whole stem grows roots allowing for a vigerous plant with many tomatoes. more roots more tomatoes. roots grow in top 4-6" of soil