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Home , Basal angiosperms, Nymphaeaceae, Ranunculaceae

“ Angiosperms”

Plant Breeding Systems Announcements

Herbarium Tour today during lab.

Lab Quiz 2 next Monday.

Keying practice this Friday, 3-5 pm, HCK 246. Phylogeny of angiosperms Angiosperms “”

Parallel venation scattered vascular bundles 1 cotyledon Tricolpate

ANITA grade •Ambor ella • •Illicium •T rimenia vessels •Austr obaileya (Jansen et al. 2007) Phylogeny of angiosperms Angiosperms “Basal angiosperms”

Parallel venation scattered vascular bundles 1 cotyledon Tricolpate pollen

Nymphaeales is a monophyletic group including Nymphaeaceae, Barclayaceae, and vessels

(Jansen et al. 2007) Nymphaeaceae (Water lily )

http://botany.csdl.tamu.edu/FLORA/tfplab/lilyp.gif

http://www.squidoo.com/VictoriaWaterLily Nymphaeaceae (Water lily family)

8 genera, 70 species (, , )

Habit:

Ben Legler

Textbook DVD WSJ Stems:

Leaves: Nymphaeaceae (Water lily family)

Inflorescence:

Flowers:

Sex of :

Ben Legler Nymphaeaceae (Water lily family)

Flower symmetry:

Perianth parts:

http://www.missouriplants.com/Whitealt/Nymphaea_odorata_calyx.jpg # of :

# of pistils/flower:

Textbook DVD KRR & DLN # of carpels/pistil:

Ovary position:

http://sevenhillslake.com/LUTEXPUM_I020720333.jpg Nymphaeaceae (Water lily family)

Fruit type:

Textbook DVD KRR & DLN Textbook DVD JRA Phylogeny of angiosperms Angiosperms “Basal angiosperms”

Parallel venation scattered vascular bundles 1 cotyledon Tricolpate pollen

Magnoliids is a monophyletic group including Magnoliaceae, Lauraceae, Piperaceae and vessels several other families

(Jansen et al. 2007) Magnoliaceae (Magnolia family)

Textbook DVD KRR Magnolia X soulangeana Magnoliaceae (Magnolia family)

2 genera, 220 species (Liriodendron, Magnolia)

Habit: Textbook DVD WSJ Magnolia grandiflora

Leaves:

Textbook DVD WSJ Liriodendron tulipifera Magnoliaceae (Magnolia family)

Inflorescence:

Flowers:

Textbook DVD WSJ Magnolia grandiflora

Sex of plant:

Textbook DVD WSJ Liriodendron tulipifera Magnoliaceae (Magnolia family)

Flower symmetry:

Perianth parts:

# of stamens:

Textbook DVD KRR

# of pistils/flower: # of carpels/pistil:

Ovary position:

Textbook DVD KRR Magnoliaceae (Magnolia family)

Fruit type:

Textbook DVD SMK & KRR

Textbook DVD KRR Early Angiosperm Flower

•Insect-pollinated •Radially symmetric •Floral parts numerous, spirally arranged and free

•Perianth of tepals Textbook DVD KRR •Perfect flower •Laminar stamens • of simple pistils, and superior ovaries

Ben Legler Phylogeny of angiosperms Angiosperms “Basal angiosperms”

Parallel venation scattered vascular bundles 1 cotyledon Tricolpate pollen

vessels

(Jansen et al. 2007) Phylogeny of (or Tricolpates) Eudicots (or Tricolpates) “Basal eudicots”

Ranunculales is a monophyletic group including , , , and 4 other families.

(Jansen et al. 2007) Ranunculaceae (Buttercup family)

Yaowu Yuan Yaowu Yuan Ranunculaceae (Buttercup family)

47 genera, 2000 species (, , , Helleborus, Ranunculus)

Habit:

http://commons.wikimedia.org/wiki/File:Helleborus_orientalis2.jpg

Leaves:

Textbook DVD KRR Ranunculaceae (Buttercup family)

Inflorescence:

Flowers:

Jim Riley

Sex of plant: Ranunculaceae (Buttercup family)

Flower symmetry:

Perianth parts:

# of stamens:

Yaowu Yuan

# of pistils/flower: # of carpels/pistil:

Ovary position:

Yaowu Yuan Ranunculaceae (Buttercup family)

Fruit type:

Textbook DVD KRR Textbook DVD KRR & DLN Papaveraceae s.s. (Poppy family)

(Hoot et al. 1997) Papaveraceae s.s. (Poppy family)

http://www.missouriplants.com/Redalt/Papaver_rhoeas_plant.jpg

Textbook DVD CSC

Eschscholzia californica California poppy

Papaver rhoeas Papaveraceae s.s. (Poppy family)

23 genera, 240 species (Argemone, Eschscholzia, )

Habit:

Stems:

http://www.missouriplants.com/Yellowalt/Argemone_mexicana_plant.jpg

Leaves:

Textbook DVD WSJ Papaveraceae s.s. (Poppy family)

Inflorescence:

Flowers:

Sex of plant:

Yaowu Yuan Papaveraceae s.s. (Poppy family)

Flower symmetry:

Perianth parts:

# of stamens:

Textbook DVD DLN # of pistils/flower: # of carpels/pistil:

Ovary position:

Yaowu Yuan Papaveraceae s.s. (Poppy family)

Fruit type:

Yaowu Yuan Textbook DVD KRR

http://www.indianetzone.com/photos_gallery/1/274_poppy_seed_fruit.jpg PLANT BREEDING SYSTEMS

Diversity and Evolution of Reproduction in Angiosperms vs. Animals

• Flowering plants are generally hermaphroditic. • Use intermediary agents. • Can reproduce asexually & sexually. • Less rigidly controlled development. • Alternation of generations. • Plant breeding systems are rarely fixed & static! Asexual Reproduction

• Reproduction of genetically identical individuals from a single parent plant.

• Main type: vegetative reproduction.

• No meiosis, no fertilization, and no recombination. Modes of Vegetative Reproduction

• – underground shoots • Tillers – aboveground shoots • Bulblets – “little bulbs” • Bulbils – veg buds • Cuttings Advantages of Asexual Reproduction

• Parent plants well-adapted to local environment will have offspring with a competitive advantage. • Less reproductive effort. • Colonization with limited dispersal. • Reproductive assurance in limited cross-pollination. Disadvantages of Asexual Reproduction

• Little if any new genetic variability. – Genetically uniform populations.

• Very narrow population niche width.

• No capabilities for travel, dormancy, and establishment that exhibit. Sexual Reproduction

• Production of offspring through meiosis and fertilization. – Offspring genetically different from parents due to recombination = genetic diversity.

• Plants can be both asexual and sexual, with a variety of forms. SUCCESSFUL POLLINATION ≠ SUCCESSFUL FERTILIZATION Hermaphroditic Flowers

• Self-compatible (SC) – Capable of self-fertilization or cross-fertilization

• Self-incompatible (SI) – Only capable of cross- fertilization – Inability of hermaphroditic plant to produce zygotes w/ self pollen Self-fertilization

• Pollen transfer within or among flowers of same individual

• ~20% of angiosperms are habitual selfers

• ~40% of angiosperms can self-fertilize Advantages of Self-fertilization

• Reproductive assurance. • Selectively advantageous by transmitting both sets of genes to offspring. – Well-adapted genotypes preserved. • Only single colonizing individual needed. • Cost-saving on male expenditure. Disadvantages of Self-fertilization

• Decreases genetic variability. • Inability to adapt to changing conditions. • Increases inbreeding depression. – Reduces heterozygosity and increases homozygosity of deleterious alleles. – Loss of vigour in offspring! Loss of Heterozygosity from Selfing

Aa x Aa A a

A AA Aa 1/4 AA 1/2 Aa a Aa aa 1/4 aa

A selfed heterozygote will yield offspring that are 50% heterozygous. Loss of Heterozygosity from Selfing

Proportion of heterozygotes is 1/2 in each successive generation.

F1: 50% of offspring heterozygous from original parent (Aa). F2: 25% F3: 12.5% F4: 6.2% F5: 3.1% F6: 1.5% Disadvantages of Self-fertilization

• Decreases genetic variability. • Inability to adapt to changing conditions. • Increases inbreeding depression. • Reproductive inefficiency. Self-incompatibility (SI)

• Inability of a fertile hermaphrodite flower to produce zygotes after self-pollination.

• Involves a biochemical reaction in the stigma or style to reject self pollen or prevent pollen tube growth.

• Genetically controlled by S-locus. – opposite S alleles attract – like S alleles repel Selfers vs. Outcrossers

• SC • SI or SC • Mostly annuals • Mostly woody perennials • Small flowers (few) • Large showy flowers (many) • Unscented flowers • Scented flowers • Nectaries & • Nectaries & nectar guides guides absent present • Similar maturation of • Differential maturation of reproductive parts reproductive parts – Anthers near stigma – Anthers far from stigma – Style included – Stigma well-exserted • All mature • Only some fruits mature • Low pollen:ovule ratio • High pollen:ovule ratio Cleistogamy (CL)

• Flowers never open and only capable of self-fertilization in bud.

• Inconspicuous, bud-like apetalous flowers that form directly into capsules.

• 488 species, across 212 genera and 49 families. – Violaceae, Fabaceae, Poaceae Cleistogamy (CL)

• Mixed mating systems -can produce both CL and open flowers on an individual.

• CL fls are a “back-up” in case pollinators scarce.

• CL occur after normal flowering period. – open fls early spring and CL fls later in season. Strategies to Prevent Self-fertilization Physical Separation of Reproductive Parts (Herkogamy)

• Within flowers • Among flowers Heterostyly

• Flowers in different individuals of the same species having 2 or 3 different style lengths – With lengths varying inversely

• 25 families of angiosperms, over 18 orders, and 155 genera. Distyly

• 2 floral morphs.

• “Thrum” flower – long filaments w/ short styles

• “Pin” flower – short filaments w/ long styles

• Only pollinations between different floral morphs are successful.

• E.g.: Primulaceae, Boraginaceae Tristyly

• 3 floral morphs

• Style long, stamens short and medium

• Style medium, stamens short and long

• Style short, stamens medium and long

• Only 3 families! Temporal Separation of Reproductive Parts (Dichogamy)

• Protandry – Anthers release pollen before stigma receptive

– Common in insect- pollinated plants Temporal Separation of Reproductive Parts (Dichogamy)

• Protogyny – Stigma receptive before pollen release

– Less common than protandry Physical Separation of Reproductive Parts

• Unisexual flowers – Staminate and carpellate flowers

• Monoecy

• Dioecy Selective Pressures for Unisexuality

• Outcrossing requirement.

• Gender resource allocation.

• Physical interference between male & female function. Monoecy

• Common in large wind- or water-pollinated plants. – Betulaceae, Fagaceae, Cyperaceae, etc.

• Common in temperate regions.

• Self-pollination possible but less likely. Dioecy

• 6% of angiosperms • Common in tropical regions and oceanic islands • Gen small fl size • 100% outcrossing, but inefficient • Sometimes controlled by sex chromosomes Polygamous Flowers

• Both bisexual and unisexual fls on the same plant or in the same population.

– Androdioecy = bisexual and staminate individuals in a population. – Andromonoecy = bisexual and staminate flowers on same individual. – Gynodioecy = bisexual and carpellate individuals in a population. – Gynomonoecy = bisexual and carpellate flowers on same individual. Evolution of Breeding Systems

• Ancestral angiosperms were SC & hermaphroditic. • SI has evolved many times. • Physical and temporal separation have evolved many times. • Dioecy has evolved many times and through different pathways. • Breeding systems not fixed and often mixed!