FRUITS AND SEEDS Fruits z Part of sexual

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FRUITS AND SEEDS

FRUITS AND SEEDS

Fruits z. Part of sexual reproduction unique to angiosperms z. Develops from fertilized ovary

Fruits z. Part of sexual reproduction unique to angiosperms z. Develops from fertilized ovary z. Protect the enclosed seeds and aids in seed dispersal z. Widely utilized as a significant food source

Fruit wall or Pericarp z. Develops from the ovary wall z. Composed of three

Fruit wall or Pericarp z. Develops from the ovary wall z. Composed of three layers youter exocarp ymiddle mesocarp yinner endocarp z. Appearance of these three layers varies among different fruit types

Fruit Types I: Simple Fruits z. Derived from the ovary of a single carpel

Fruit Types I: Simple Fruits z. Derived from the ovary of a single carpel or several fused carpels z. Can be fleshy or dry

Type I. a: Simple fleshy fruit z. Derived from the ovary of a single

Type I. a: Simple fleshy fruit z. Derived from the ovary of a single carpel or several fused carpels z. Often soft and juicy z. Seed dispersal occurs when an animal eats the fruit z. Types of simple fleshy fruits y. BERRY y. DRUPE -HESPERIDIUM -POME -PEPO

Berry z Thin exocarp z Soft fleshy mesocarp z Endocarp with one to many

Berry z Thin exocarp z Soft fleshy mesocarp z Endocarp with one to many seeds z Tomatoes, grapes and dates

Hesperidium z Berry with a tough leathery rind z Oranges, lemons, and other citrus

Hesperidium z Berry with a tough leathery rind z Oranges, lemons, and other citrus fruit. S

Pepo z Tough outer rind that has both receptacle tissue and exocarp z Mesocarp

Pepo z Tough outer rind that has both receptacle tissue and exocarp z Mesocarp and endocarp are fleshy z All members of the squash family (pumpkins, melons, and cucumbers)

Drupe z Thin exocarp z Fleshy mesocarp z Hard stony endocarp which encases the

Drupe z Thin exocarp z Fleshy mesocarp z Hard stony endocarp which encases the seed z Cherries, peaches, and plums Exocarp Mesocarp Endocarp

Pome z Fleshy part develops from the enlarged base of the perianth (calyx and

Pome z Fleshy part develops from the enlarged base of the perianth (calyx and corolla) that is fused to the ovary wall z Apples and pears

Accessory fruits z. Contain flower parts other than the ovary z. Both the pepo

Accessory fruits z. Contain flower parts other than the ovary z. Both the pepo and pome are example

Type I. b: Simple dry fruits z. Derived from the ovary of a single

Type I. b: Simple dry fruits z. Derived from the ovary of a single carpel or several fused carpels z. Pericarp may be tough and woody or thin and papery z. Two types: xdehiscent xindehiscent

Dry dehiscent fruits z. Split open at maturity to release seeds z. Wind often

Dry dehiscent fruits z. Split open at maturity to release seeds z. Wind often aids seed dispersal z. Types characterized by how they open: * Follicle - splits open along one seam (magnolia and milkweed) * Legume - splits open along two seams (beans and peas) * Capsule - several pores or slits (cotton and poppy)

Legume - pea z Legume pod splits along two seams to disperse seeds

Legume - pea z Legume pod splits along two seams to disperse seeds

Capsule z Cotton fruit is a capsule splitting open along five lines z Seeds

Capsule z Cotton fruit is a capsule splitting open along five lines z Seeds are covered with long hairs (trichomes) which are the commercial cotton fiber

Indehiscent fruits z. Do not split open to release seeds z. Common types y.

Indehiscent fruits z. Do not split open to release seeds z. Common types y. Achene y. Samara y. Grain y. Nut

ACHENES SAMARAS z One-seeded fruit z Pericarp free from the seed z Sunflower “seeds”

ACHENES SAMARAS z One-seeded fruit z Pericarp free from the seed z Sunflower “seeds” z Winged achenes z Dispersed by wind z Fruit in maple trees and ash trees

Grains z. Also called caryopsis z. Single seeded fruits z. Pericarp fused to seed

Grains z. Also called caryopsis z. Single seeded fruits z. Pericarp fused to seed coat z. Fruits of all cereal grasses: wheat, rice, corn and barley

Wheat grain Fused seed coat and ovary wall layers

Wheat grain Fused seed coat and ovary wall layers

Nuts z One-seeded fruits z Hard stony pericarps z Hazelnuts, chestnuts, and acorns z

Nuts z One-seeded fruits z Hard stony pericarps z Hazelnuts, chestnuts, and acorns z Other things commonly called nuts that are not true nuts but are actually seeds

Fruit Types II: Aggregate fruits z. Develop from a single flower with many separate

Fruit Types II: Aggregate fruits z. Develop from a single flower with many separate carpels z. Raspberries and blackberries z. Strawberries also contain accessory tissue y. Seeds on the surface are actually separate achenes inserted on the enlarged, fleshy, red receptacle

Raspberries and Blackberries

Raspberries and Blackberries

Aggregate-Accessory Fruit z Strawberries also contain accessory tissue z Seeds on the surface are

Aggregate-Accessory Fruit z Strawberries also contain accessory tissue z Seeds on the surface are actually separate achenes on enlarged, fleshy receptacle

Fruit Types III: Multiple fruits z Result from the fusion of ovaries from many

Fruit Types III: Multiple fruits z Result from the fusion of ovaries from many separate flowers on an inflorescence z Figs and pineapples are examples of multiple fruits one of many ovaries that are fused together

Seed Structure and Germination

Seed Structure and Germination

Seeds z. Develop from the fertilized ovules z. Include an embryonic plant and some

Seeds z. Develop from the fertilized ovules z. Include an embryonic plant and some form of nutritive tissue within a seed coat z. Because of the stored nutrients many seeds are valuable foods

Dicots and monocots z. Refers to the number of seed leaves or cotyledons present

Dicots and monocots z. Refers to the number of seed leaves or cotyledons present in the seed z. Dicot seeds have two cotyledons z. Monocots have one cotyledons

Dicot seed z. Cotyledons attached to and enclose the embryonic plant z. Cotyledons occupy

Dicot seed z. Cotyledons attached to and enclose the embryonic plant z. Cotyledons occupy the greatest part of the seed z. Cotyledons have absorbed the nutrients from the endosperm which may be entirely used up

Dicot seed - Lima bean z Thin seed coat z Hilum and micropyle visible

Dicot seed - Lima bean z Thin seed coat z Hilum and micropyle visible on surface * Hilum - attachment * Micropyle - opening in the integuments z If the seed coat is removed the two large food-storing cotyledons are visible

Dicot embryo z. Consists of : y. Epicotyl - part that develops into the

Dicot embryo z. Consists of : y. Epicotyl - part that develops into the shoot; typically has embryonic leaves - also called a plumule y. Hypocotyl - portion of embryo between cotyledon attachment and radicle (between stem and root) y. Radicle - the embryonic root

Monocot seed z. Cotyledon transfers food from the endosperm to the embryo z. In

Monocot seed z. Cotyledon transfers food from the endosperm to the embryo z. In several monocot families large amounts of endosperm are present

Monocot seeds - Corn kernel z. Reminder: a grain is a one-seeded fruit in

Monocot seeds - Corn kernel z. Reminder: a grain is a one-seeded fruit in which the seed coat is fused to the pericarp z. Extensive endosperm occupies much of the seed z. Small embryo with a single cotyledon z. Presence of a coleoptile and the coleorhiza

Seed germination z Absorption of water z Emergence of the radicle z Shoot emerges:

Seed germination z Absorption of water z Emergence of the radicle z Shoot emerges: y. In dicots the hypocotyl elongates and breaks through the soil y. In monocots the coleoptile emerges protecting the epicotyl tip z Soon after the tissues are exposed to sunlight, they develop chlorophyll and begin to photosynthesize

Tomatoes z Native to Andes Mts in South America z First cultivated in Mexico

Tomatoes z Native to Andes Mts in South America z First cultivated in Mexico z Spanish Conquistadors introduced tomatoes to Europe in the 16 th century

What is in a name? z. Name among native peoples in Mexico was tomatl

What is in a name? z. Name among native peoples in Mexico was tomatl z. In Europe there were lots of names for this fruit - love apple or pomme d’amour was the French name z. Scientific name Lycopersicum esculentum (meaning edible wolf peach)

Poisonous Relatives z. Member of the family Solanaceae (called the potato or tomato family)

Poisonous Relatives z. Member of the family Solanaceae (called the potato or tomato family) z. Family known for its poisonous plants z. Also called the nightshade family because of deadly nightshade and henbane z. Also called tobacco family

Suspect Plant z. Because of the poisonous relatives, tomatoes were suspected by many as

Suspect Plant z. Because of the poisonous relatives, tomatoes were suspected by many as poisonous z. Hard reputation to live down z. In 1820 Col. Robert Johnson ate a bushel of tomatoes in front of a crowd to prove they were safe

Popular “vegetable” z. Although botanically it is simple fleshy fruit (a berry), in 1893

Popular “vegetable” z. Although botanically it is simple fleshy fruit (a berry), in 1893 the Supreme Court ruled it was a vegetable z. Widely used in fresh, canned, dried, pickled, and processed varieties z. Also a favorite experimental tool - used in space shuttle, genetic engineering, and cloning experiments

Apples - Malus pumila z Family Rosaceae z Long history of use z One

Apples - Malus pumila z Family Rosaceae z Long history of use z One of the first trees cultivated z Native to Caucasus Mts of western Asia z Many legends associated with apples

Apple Varieties z. Pome - simple accessory fruit z. Hundreds of varieties exist but

Apple Varieties z. Pome - simple accessory fruit z. Hundreds of varieties exist but only a few dominate the market y. Delicious, Rome, Gala, Mc. Intosh z. Most apple trees are produced by grafting rather than by seeds z. Grafting creates thousands of identical copies with the desired traits

Citrus Fruits

Citrus Fruits

Citrus Fruits - Oranges z. Members of the family Rutaceae z. Fruit is a

Citrus Fruits - Oranges z. Members of the family Rutaceae z. Fruit is a hesperidium z. Rind impregnated with oil glands (oils important for perfumes and cosmetics) z. Individual carpels filled with one-celled juice sacs z. Fruits high in Vitamin C

Citrus Fruits z. Most citrus are native to southeast Asia z. Citrons first citrus

Citrus Fruits z. Most citrus are native to southeast Asia z. Citrons first citrus fruit introduced to Mediterranean countries during Greek and Roman times z. Sweet oranges not introduced till 16 th century

Introduction to New World z. Spanish and Portuguese explorers introduced citrus to New World

Introduction to New World z. Spanish and Portuguese explorers introduced citrus to New World z. Sour oranges grown in Florida by 1565 z. Sweet oranges introduced after 1821 grafted onto sour orange rootstock z. Florida remains leading orange-producing state for juices z. Grapefruit developed in Caribbean (pummelo x orange)

Pummelos

Pummelos

Navel Orange z. Seedless orange - propagated asexually z. First developed in Brazil by

Navel Orange z. Seedless orange - propagated asexually z. First developed in Brazil by an American missionary in 19 th century z. Two seedlings introduced to California in 1873 - believed that all navel oranges today are descendants of these two trees

Chestnuts - Castanea dentata z Member of the Fagaceae - Oak Family z Nuts

Chestnuts - Castanea dentata z Member of the Fagaceae - Oak Family z Nuts have a long history of use z Nuts produced in groups of 3 surrounded by spiny burr (actually bracts)

Spiny bracts Individual nuts

Spiny bracts Individual nuts

Chestnuts z American chestnut tree was once one of the most abundant trees in

Chestnuts z American chestnut tree was once one of the most abundant trees in North American forests z Wood widely used for furniture, shingles, poles, ships masts

Chestnut Blight z. Fungal disease first reported in 1904 in New York z. Spread

Chestnut Blight z. Fungal disease first reported in 1904 in New York z. Spread throughout range from Atlantic Coast to Mississippi River z. Estimated 1 billion chestnut trees died z. Chestnuts can resprout from roots but eventually will succumb to disease z. Research on blight resistant trees

Durian z Fruit native to southeast Asia, Malaysia, Thailand, Indonesia z Called “King of

Durian z Fruit native to southeast Asia, Malaysia, Thailand, Indonesia z Called “King of Fruits”

Durians z. Large fruits - 10 -15 lbs z. Often collected from wild although

Durians z. Large fruits - 10 -15 lbs z. Often collected from wild although cultivation is spreading z. Not available outside of Asia z. Custard-like pulp that is said to be heavenly

Durians z. Said to be the most delicious fruit on Earth and the worst

Durians z. Said to be the most delicious fruit on Earth and the worst smelling z. Sold in open markets but prohibited in many cities z“No durians allowed”