Question

What is the family of Rhubarb ?

• A. Apiaceae
• B. Euphorbiaceae
• C. Convolvulaceae
• D. Polygonaceae

Hint:

Rhubarb (Rheum species) belongs to the Polygonaceae family. Key characteristics of this family often include swollen stem nodes and a sheathing stipule (ocrea) at the leaf base. Other common members are buckwheat and sorrel.

Answer 1

The Correct Option is D

Rhubarb (genus Rheum) is a perennial vegetable known for its fleshy, tart leafstalks (petioles), which are used in cooking, often for desserts like pies and crumbles. To identify its family, we need to know its botanical classification:
(1) Apiaceae (Carrot family): Characterized by umbel inflorescences (e.g., carrots, parsley, celery).
(2) Euphorbiaceae (Spurge family): A diverse family, often with milky latex and unique flower structures (cyathia) (e.g., poinsettia, castor bean).
(3) Convolvulaceae (Morning glory family): Mostly climbing plants or shrubs with funnel-shaped flowers (e.g., sweet potato, morning glory).
(4) Polygonaceae (Buckwheat or Knotweed family): Characterized by swollen nodes on the stems and often by the presence of a membranous sheath called an ocrea at the base of the petiole. Rhubarb (Rheum spp.) belongs to this family. Other members include buckwheat, sorrel, and knotweed. Therefore, the family of Rhubarb is Polygonaceae. Polygonaceae

Answer 2

Relative-based recall:
Instead of matching family descriptions one by one, this can be solved by recalling which common plants share Rhubarb's family. Rhubarb (Rheum rhabarbarum) belongs to the same family as sorrel, dock and buckwheat - all in Polygonaceae, easily identified by their swollen, jointed stem nodes and papery ocrea (a sheath wrapping the stem at each leaf base).

None of the remaining families - Apiaceae (umbel-flowered herbs like carrot), Euphorbiaceae (latex-bearing plants) or Convolvulaceae (twining vines like morning glory) - share this nodal/ocrea feature, so they can be ruled out directly.

Hence, the family of Rhubarb is Polygonaceae.