Question

Though the plant is not diseased, yet we find the stem of plant is swollen, is the reason any damage or blockage in xylem and phloem tissue

Answer 1

There can be several reasons for this condition. The presence or invasion by any microorganisms can also leads to the tumor condition which make it appear like swollen or it may be due to any diseased condition or possibly due to the blockage in xylem and phloem tissue.