What is the meaning of vexillary or papilionaceous aestivation?

What is the meaning of vexillary or papilionaceous aestivation?
  1. When the margins of sepals or petals overlap one another but not in any particular direction
  2. When sepals or petals overlap one another in a particular direction
  3. When the largest petal overlaps the two lateral petals which in turn overlap the two smallest anterior petals
  4. When sepals or petals just touch one another at the margin, without overlapping

Solution

Vexillary or papilionaceous aestivation refers to a situation where there are five petals in a flower, and the largest petal (standard) overlaps the two smallest anterior petals.

Asked in: NCERT

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