The modification of the stem for support is in the form of stem tendrils, which are found in plants like gourds (cucumber, pumpkin, watermelon) and grapevines.
Chrysanthemum: The stem is modified where lateral branches arise from the basal and underground part of the stem, grow horizontally under soil, and emerge obliquely as leafy shoots (not for support).
Maize and Sugarcane: These plants have modified roots(Stilt roots) for support.
Rhizophora: This plant exhibits a root modification for respiration. Potato and Colocasia: These are underground stem, modified for storage of food.