Double fertilization in angiosperms

Pollen tube development and ovary stigma pollen style pollen tube sperm cell veg. cell embryo sack integu- ment funicle chalaza antipodal cells central veg. nucleus egg + synergids ovary vs: vegetative cell gs: generative cell sp: sperm cell pt: pollen tube POLLEN PISTIL

Structre of embryo sac Papaver rhoeas embryo sac egg cell central vegetative nucleus (polar nuclei) antipodal cells integument

Pollen tube on pistil surface

Double fertilization (diploid vegetative cell)

Double fertilization 1st sperm cell 2nd sperm cell

Development of embryo zygote  embryo dipl. veg. cell  triploid nucleus  nutritive tissue (endosperm) 1st sperm cell + egg cell → 2nd sperm cell +

Ovule maturation into seed  fertilized egg cell  germ / embryo  fertilized veg. nucleus  inner nutritive tissue / endosperm  nucellus  outer nourishing tissue / perisperm  integument  seed coat / testa  ovary  fruit  wall of ovary  fruit wall / pericarp  seed germination: embryo  seedling

3 rye seed coat endosperm cotyledon radicle cotyledon germ embryo fruit wall seed coat endo- sperm peri- sperm 4: almond Seeds: 2: pepper 1: castor plant

A. poppy m: seed coat e: endosperm cs: germ Seeds and appendages C. common yew ar: arille (seed envelope) mh: seed coat B. greater celandine el: elaiosome

SEEDS Campanula sp. seed coat (testa) Heuchera sp. seed coat (testa)

1. gyak_Lini semen seed coat with cuticle storing ground tissue (fatty oil) embryo mucilage cells pigment cells seed of Linum usitatissimum

1. gyak_Lini semen_zsíros o. seed coat with mucilage cells pigment cells cuticle seed of Linum usitatissimum storing ground tissue (fatty oil)

Sinapis nigrae semen_4x epidermis seed of Sinapis nigra storing ground tissue (fatty oil)

THE FRUIT

Fruit types True fruits: from ovary Pseudofruits (false fruits): ovary + other flower parts (e.g. receptacle, tepals, bracts) rosehip (Rosa canina)

Fruit types Number of carpels: monocarpellary/unicarpellary polycarpellary Degree of carpel fusion: choricarpous / apocarpous (a) coenocarpous - syncarpous (b) - paracarpous (c) monocarpous follicle polycarpous capsule paracarpous syncarpous HypericumLilium /Flowers/Flower%20parts.pdf a bc

Classification of Fruits Other aspects: position of ovary dry or fleshy opens or remains closed Fruit types: I. DRY DEHISCENT FRUITS II. DRY INDEHISCENT FRUITS III. SIMPLE FLESHY FRUITS IV. COMPOUND FRUITS

I. DRY, DEHISCENT FRUITS (4 types) 1. Follicle - monocarpous, superior ovary - 1 opening (suture), multiple seeds e.g. milkweed (Asclepias syriaca), forking larkspur (Consolida regalis) 2. Legume - monocarpous, superior ovary - 2 sutures (ventral + dorsal), many seeds e.g. bean family (Fabaceae) lomente.g. Sophora spirale.g. clover one-seedede.g. sainfoin indehiscente.g. peanut

I. DRY, DEHISCENT FRUITS 3. Silique mustard family (Brassicaceae) 2 carpels superior ovary opens by 2 sutures false carpellary wall/ replum Silicle: as long as broad min. 3x longer than broad e.g. black mustard (Brassica nigra) e.g. shepherd’s purse (Capsella bursa-pastoris) oilseed rape (Brassica napus)

I. DRY, DEHISCENT FRUITS 4. Capsule 2 or more carpels, inferior or superior ovary septicidal – opens along the fusion of carpels e.g. thorn apple (Datura), Colchicum loculicidal – opens along the main vein of carpel e.g. onion (Allium cepa) septifragil – opens along the line of carpel fusion AND along the main carpel vein e.g. castor plant (Ricinus) transverse – upper part separating like lid of box e.g. henbane (Hyoscyamus) toothed e.g. primrose (Primula) poricidal – releases seeds through pores e.g. poppy (Papaver)

Capsule Types poricidaltoothed loculicidal transverse septifragil poppy (Papaver) thorn apple Datura stramonium henbane (Hyoscyamus) septicidal

II. DRY, INDEHISCENT FRUITS (8 types) 1. Grain / Caryopsis - unicarpellate, superior ovary - 1-seeded, fruit wall fuses with seed coat e.g. grass family (Poaceae) 2. Achene - 1 carpel, superior, unilocular ovary - 1-seeded - usually in fruit aggregates e.g. buttercup family (Ranunculaceae) 3. Double achene / schizocarp - 2 carpels, inferior ovary - mericarps held together by carpophor e.g. carrot family (Apiaceae) achenes of Clematis vitalba achenes of Carum carvi

Foeniculi fructus km4x shizogenous oil cavity epidermis collateral closed bundles endosperm with starch Foeniculum vulgare

Carvi fructus km4x Carum carvi storing ground tissue with starch shizogenous oil cavity

4. gyak_Anethi fructus shizogenous oil cavity endosperm Anethum graveolens

II. DRY, INDEHISCENT FRUITS 4. Acorn / Nut - 2 or more carpels, superior or inferior ovary - bony (sclerenchymatous) pericarp - fruit sits in cupule: formed from bracts or receptacle e.g. hazelnut, oak, beech, sweet chestnut 5. Nutlet - smaller form of nut, 2 or more carpels - sclerified exocarp protects the seeds (usually 4) e.g. mint family (Lamiaceae) borage family (Boraginaceae) acorns of sessile oak (Quercus petraea)

II. DRY, INDEHISCENT FRUITS (8 types) 6. Cypsela - 2 carpels, inferior ovary - achene-like fruit - derived from florets of capitulum - calyx often modified (e.g. pappus) – seed dispersal e.g. aster family (Asteraceae) 1 pappus dandelion (Taraxacum officinale)

II. DRY, INDEHISCENT FRUITS 7. Samara - 2 carpels, superior ovary - type of achene - pericarp → membrane-like wing e.g. elms (Ulmus), ashes (Fraxinus) 8. Double samara - schizocarp with wings - fork-like carpophor e.g. maples (Acer) double samara of Acer campestre

III. SIMPLE FLESHY FRUITS (6 types) 1. Berry - outer pericarp (exocarp): thin, leather-like - middle layer (mesocarp) and inner layer (endocarp) of fruit wall: fleshy, juicy - 1 or more seeds – e.g. grapes (Vitis) 2. Pepper fruit - inflated berry, pericarp may dry e.g. paprika (Capsicum annuum)

III. SIMPLE FLESHY FRUITS 3. Hesperidium - many carpels, superior, multilocular ovary exocarp: vivid color (yellow, orange), with essential oil cavities mesocarp: white, sponge-like parenchyma endocarp: fluid-filled vesicles (hairs/trichomes) e.g. orange, lemon (Citrus sp.) grapefruit (Citrus paradisi)

Citrus termésfal km4x epidermis lysigenous oil cavity ground tissue pericarp of lemon

Aurantii pericarpium_10x epidermis pericarp of orange lysigenous oil cavity ground tissue

Capsici fructus_4x epidermis collateral closed bundle pericarp of paprika giant cells ground tissue

III. SIMPLE FLESHY FRUITS 4. Pepo - usually from 3 carpels, inferior ovary - hard-rind pericarp e.g. cucurbit family (Cucurbitaceae) exocarp: leather-like mesocarp: collenchyma, juicy parenchyma endocarp: fleshy partition walls and seeds pumpkin (Cucurbita pepo)

III. SIMPLE FLESHY FRUITS 5. Stone fruit / Drupe 1 or 2 carpels, superior or half-superior ovary exocarp / skin: leather-like, colored mesocarp / flesh: juicy, fleshy endocarp = shell/stone: stone cells (sclereids), seed within endocarp e.g. plum, sweet cherry, sour cherry, peach (Prunoideae), walnut (Juglans), olive (Olea europaea) plum (Prunus domestica)

Dió termés szőrök40x epidermis multicellular glandular trichomes head stalk pericarp of walnut ground tissue

III. SIMPLE FLESHY FRUITS 6. Pome - false fruit (receptacle, sepals take part in fruit formation) - many carpels, inferior ovary, apocarpous - cartilage-like endocarp around seed- cavities, surrounded by fleshy mesocarp e.g. apple (Malus), pear (Pyrus) seeds original fruit wall around seeds (endocarp in false fruit) quince (Cydonia oblonga) apple (Malus domestica)

IV. COMPOUND FRUITS (6 types) 1. Aggregate of follicles -apocarpous, superior ovary e.g. hellebore (Helleborus) 2. Aggregate of drupelets - apocarpous ovary e.g. raspberry, blackberry (Rubus sp.) AGGREGATE FRUITS ← 1 FLOWER : Helleborus odorus 2. 1.

IV. COMPOUND FRUITS 3. Aggregate of achenes - apocarpous ovary - fleshy receptacle with achenes on its outer surface e.g. strawberry (Fragaria) -fleshy, cup-like receptacle with achenes inside e.g. rose hip (Rosa canina) receptacle achenes receptacle Fragaria vesca

Rosae pseudofructus_10x epidermis collateral closed bundle (p: phloem, x: xylem) p x Ca(COO) 2 crystals pseudofruit of rose hip trichomes

Juniperi pseudofructus_4x epidermis lysigenous oil cavity ground tissue pseudofruit of juniper

IV. COMPOUND FRUITS 2. Multiple of achenes single achene fruits surrounded by fleshy inflorescence axis e.g. fig (Ficus carica) 3. Multiple of berries fleshy fruits (berries) surrounded by fleshy bracts e.g. pineapple (Ananas comosus) 1. Multiple of nutlets nutlets covered by fleshy tepals e.g. mulberry (Morus) MULTIPLE FRUITS ← INFLORESCENCE