indehiscent

Indehiscent is an adjective used in botany to describe fruits or seed cases that do not split open at maturity to release their seeds. In contrast, dehiscent fruits rupture or separate along designated lines to disperse seeds when ripe. In indehiscent fruits, the seeds remain enclosed within the pericarp or seed coat throughout ripening, so dispersal relies on external agents or on the fruit’s dispersal structures rather than internal opening.

Common examples include fleshy indehiscent fruits such as drupes (for example peaches, plums, and olives) and berries (grapes, kiwifruit, blueberries). In these fruits the seeds stay inside a closed, usually fleshy pericarp. Dry indehiscent fruits include nuts (acorns, hazelnuts), grains or caryopses (wheat, corn, rice), and many achenes such as sunflower seeds, whose seed lies inside a simple, closed outer layer. Each type has adaptations for dispersal: drupes and berries often rely on animals; nuts may persist on the plant or detach with their tough shell; grains rely on wind or mechanical dispersal, and achenes may be dispersed by animals or weather.

The term indehiscent derives from Latin in- “not” and dehiscere “to gape, open” and is used to distinguish these fruits from dehiscent fruits, such as legumes, siliques, and capsules, which rupture to release seeds.