Fruit and Seeds

• Fruits


  Mature ovaries or pistils of flowering plants and any associated accessory part

  
• Accessory part


  Attached to the fruit but not derived directly from the ovary or ovaries
• Pericarp


  Fruit wall, derived from the mature ovary wall. Sometimes divisible into layers: endocarp, mesocarp, and exocarp

  
• Fruit types based on fruit development


  • Simple (derived from a single pistil of one flower)
  • Aggregate (derived from multiple pistils of a single flower, thus having an apocarpous gynoecium)
  • Multiple (derived from many coalescent flowers)

  
• Unit fruit


  The component derived from an individual pistil in aggregate or multiple fruits

  
• Infructescence


  A mature inflorescence in fruit

  
• Criteria for classifying simple fruit types and unit fruit types


  • Whether fleshy (succulent) or dry at maturity
  • Whether indehiscent (not splitting open at maturity) or dehiscent (splitting open along definite pores, slits, or sutures)
  • If dehiscent, the type (e.g., location, shape, and direction) of dehiscence
  • Carpel and locule number, including presence of septa
  • Seed/ovule number
  • Placentation
  • Structure of the pericarp wall
  • Ovary position

  
• Achene


  One-seeded dry indehiscent fruit with the seed attached to the pericarp at a single point

  
• Achene


  • Unit fruit of sunflower
• Anthocarp or Diclesium


  Achene/nut, surrounded by the persistent and accrescent perianth
• Anthocarp or Diclesium


  • Pontederia or Nyctaginaceae

  
• Grain or Caryopsis


  One-seeded dry indehiscent fruit with the seed coat adnate to pericarp wall

  
• Germ


  Embryo of grain crops
• Bran


  Pericarp and seed coat together
• Grain or Caryopsis


  • All Poaceae (grass) are this fruit type

  
• Nut


  A one-seeded, dry indehiscent fruit with a hard pericarp, usually derived from a one-loculed ovary

  
• Nutlet

  A small nutlike fruit, for example, the mericarps of the Boraginaceae and Lamiaceae

  
• Samara


  A winged, dry, usually indehiscent fruit

  
• Samara


  • Acer (maple) and Ulmus (elm)
• Tryma


  A nut surrounded by an involucre that dehisces at maturity
• Tryma


  • Carya (pecan)
• Utricle


  A small, bladdery or inflated, one-seeded, dry fruit; they are essentially achenes in which the pericarp is larger than the mature seed

  
• Utricle


  • Atriplex (salt bush)
• Capsules


  Generally dry (rarely fleshy), dehiscent fruits derived from compound (multicarpeled) ovaries

  
• Types of capsules based on dehiscence


  • Loculicidal (longitudinal lines of dehiscence radially aligned with the locules)
  • Septicidal (longitudinal lines of dehiscence radially aligned with the ovary septa)
  • Circumscissile (transverse line of dehiscence typically forming a terminal lid or operculum)
  • Septifragal or valvular (valves break off from the septa)
  • Poricidal (dehiscence occurring by means of pores)
  • Acrocidal (dehiscing by means of apical slits)
  • Basicidal (dehiscing by means of basal slits)
• Follicle


  A dry, dehiscent fruit derived from one carpel that splits along one suture

  
• Follicle


  • Unit fruits of Magnolia

  
• Legume


  A dry, dehiscent fruit derived from one carpel that splits along two longitudinal sutures, the diagnostic fruit type of the Fabaceae (the legume family)

  
• Loments


  Legumes that have become secondarily modified to split transversely into one-seeded segments

  
• Indehiscent legumes


  Legumes that do not split open at all (e.g., peanut)

  
• Silicles and siliques


  Dry, dehiscent fruits derived from a two-carpeled ovary, dehiscing along two sutures, with an outer rim (the replum) and a persistent, thin partition (the false septum). Silicle is about as broad or broader than long, silique is longer than broad. Characteristic fruit types of the Brassicaceae, the mustard family.

  
• Schizocarp


  A dry, dehiscent fruit type derived from a two or more loculed compound ovary where the locules separate at maturity. The individual unit fruits containing each locule can be defined based on other simple fruit types.

  
• Schizocarp of follicles


  A fruit where the (generally two) carpels of a pistil split at maturity, each carpel developing into a unit follicle

  
• Schizocarp of follicles


  • Asclepias, milkweed
• Schizocarp of mericarps


  The carpels of a single ovary split during fruit maturation, each carpel developing into a unit mericarp
• Schizocarp of mericarps


  • Apiaceae

  
• Mericarps


  Portions of the fruit that separate from the ovary as a distinct unit completely enclosing the seed(s), in the Apiaceae the two mericarps are attached to one another via a stalk like structure called the carpophore

  
• Schizocarp of nutlets


  A single ovary becomes lobed during development, the lobes developing at maturity into nutlets, which split off
• Schizocarp of nutlets


  • Boraginaceae and most Lamiaceae, which have gynobasic styles attached between the ovary lobes
• Berry


  The general, unspecialized term for a fruit with a succulent pericarp, as in Vitis, grape