adnation

plant anatomy

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July 23, 2026

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Adnation is a botanical term describing the fusion of plant parts that are typically unlike, such as when a calyx (sepals) is fused to the ovary. This fusion can occur along the margins of these parts.1

In angiosperms, adnation is observed when stamens fuse with the corolla (petals) to form a staminal tube, or when the calyx, corolla, and stamens fuse to create a hypanthium, which is a cuplike structure surrounding the carpels. This phenomenon is a common aspect of plant anatomy, contributing to the diverse structures found in flowering plants.23

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angiosperm
General features
…petals in the morning glory; adnation is the fusion of different organs—for example, the stamens fused to petals in the mint family (Lamiaceae). The basic floral pattern consists of alternating whorls of organs positioned concentrically: from outside inward, sepals, petals, stamens, and carpels (Figure 12). It is possible in most…
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…petals in the morning glory; adnation is the fusion of different organs—for example, the stamens fused to petals in the mint family (Lamiaceae). The basic floral pattern consists of alternating whorls of organs positioned concentrically: from outside inward, sepals, petals, stamens, and carpels (Figure 12). It is possible in most…
Read More