Fruit Morphology and Development

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Fruit Morphology and Development
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Fruit develops from the flowers

• Flower parts - Perfect flower

Androecium (set of stamens)
Corolla (group of petals)
Gynoecium (set of carpels)
Calyx (group of sepals)
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Fruit develops from the flowers

• Flower parts - Imperfect flower

Male
Female
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Flower typesFloral parts arrangements

• Attachment of floral parts
• Position of ovary

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Fruit ClassificationSeed-bearing structure
derived from a flower

• Fleshy fruit
• Berry
• Drupe
• Pome
• Pepo

• Dry fruit
• Dehiscent - splits when ripe
• Indehiscent - one carpel
• Aggregate fruit
• Multiple fruit

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Fleshy fruit BerriesOne pistil (carpel) One or
many seed
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Fleshy fruit DrupesOne seededSeed within stony
endocarp

• Peach, plum, apricot, cherry
• Skin exocarp
• Eat mesocarp
• Pit endocarp

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Fleshy fruit DrupesOne seededSeed within stony
endocarp

• Almond
• Mesocarp dries and separates
• Endocarp is hard to soft
• Eat seed

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Fleshy fruit PomesLeathery carpelsEdible
portion is receptacle
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Fleshy fruit PeposInferior flower, gt 1
carpelReceptacle surrounds pericarp to form rind

• Watermelon
• Cucumber
• Squash
• Pumpkin

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Dry fruit DehiscentSplit open when ripe

• Beans
• Peas

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Dry fruit IndehiscentSingle carpelDoes not
split when ripe

• Achene
• One seeded, free from pericarp
• Strawberry, sunflower
• Nut
• Similar to achene
• Enclosed by pericarp (leathery in chestnut, woody
  in walnut)
• Husk (shuck) is fusion of sepals, bracts,
  bracteoles.

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Aggregate FruitMany ovulesOne flower
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Multiple fruitMany flowersAlong a common axis
or inflorescence
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Fruit development Definitions

• Maturation
• Process of development
• Leads to maturity ability to ripen properly
• Ripening
• Following step in fruit development
• Mature fruit becomes fully edible
• Senescence
• Final step in fruit development
• Deterioration
• Leads to death

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Fruit Growth PatternSigmoid pattern Pomes,
pecans, strawberry

• Slow
• Rapid, cell division and expansion
• Slow, leveling off of growth

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Fruit Growth PatternDouble sigmoid Peach, plum,
cherry

• Slow
• Rapid, cell division
• Slow, pit hardening
• Rapid, cell expansion
• Slow

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Fruit Growth PatternDouble Sigmoid

• Late and early ripening peaches differ in length
  of STAGE II

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Fruit Size

• Fruit size is inversely proportional to fruit
  number

This is why fruit is thinned.
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What you should learn from this lab

• Where a fruit comes from
• Flower types
• Fruit classification
• Basic fruit morphology
• Fruit development
• Terminology
• Fruit growth patterns
• Effect of seed number
• Effect of thinning
• ID of fruits and their seed

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Laboratory Procedure

• Fruit displays
• Drupes/Stone fruit - 2
• Pome fruit - 2
• Berries
• Nuts
• Multiple/aggregate fruit
• Pit and seed display
• Thinned vs. Unthinned
• Mount pressed leaves in book

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Laboratory Procedure

• Answer work sheets
• Drupes/Stone fruit - 5 pts
• Pome fruit - 5 pts
• Misc. Fruit/Seed - 10 pts
• Thinned vs. Unthinned - 5 pts
• Fruit Development Exercise on Homepage (15pts)
• Compare fruit development for pecan, pear and
  peach
• Answer questions on Homepage and submit to
  teaching assistant