Pollination Defn.?

Pollination Def’n: transfer pollen from stamen to stigma Carpel = pistil

Life Cycle Sporic meiosis: Gametophytes make gametes BY MITOSIS Sporophyte makes meiospores BY MEIOSIS Two bodies/one cycle: alternation of generations Spore: cell grows into organism w/o joining with another cell

Life Cycle Overview:

Life Cycle Overview: Fertilization: union sperm with egg to form zygote

Floral variation Parts may be fused Like parts: connation (ex., petals to petals) Unlike parts: adnation (ex., stamens to petals) Snapdragon flower Anisacanthus (Acanthaceae) flower

Floral variation Flower with stamens and pistil: perfect flower Another kind of perfection….

Floral variation Some flowers imperfect. Pistillate or staminate Pistillate flowers Sagittaria Staminate flowers Sagittaria

Floral variation Pistillate & staminate flowers on separate individuals: Dioecy (MUST outcross) Monoecy: both sexes on same individual. Flower missing one or more sets parts: incomplete flower All imperfect flowers incomplete! Who am I?

Floral variation Some flowers grouped: inflorescence Special type: head. Ex, sunflower Often: ray & disk flowers ray flowers disk flowers

Pollination as Mutualism Most flowers pollinated by animals Exceptions: wind pollinated (anemophily) water pollinated (hydrophily) Usually mutualism (+,+) Plant: pollen transferred Animal: “reward” Animal Reward…

Rewards Pollen: high protein Renewed by: Also lipids, minerals, starch sequential anther dehiscence (multiple stamens) poricidal anthers (buzz pollination)

Rewards Nectar: sugary fluid produced by nectaries Renewable reward! 10-60% mono- or disaccharides amino acids too (butterfly flowers) Renewable reward! Plant benefit?

Pollination Benefits animal pollination (to plant) 1) Directed dispersal pollen: Floral cues and attractants Learning decreases “handling time” “Floral constancy:” visit single species on foraging trip Bumblebee visits to touch-me-not

Pollination Benefits of animal pollination stigma style ovary 2 ovules 2) Style as “selective racetrack” 1 pollen grain fertilizes 1 ovule Pollen grains stigma style ovary 2 ovules

Pollination Benefits of animal pollination stigma style ovary 2 ovules 2) Style as “selective racetrack” Pollen tubes How many can fertilize an ovule? Pollen grains stigma pollen tubes style ovary 2 ovules

Pollination Benefits of animal pollination stigma style ovary 2 ovules 2) Style as “selective racetrack” Pollen tubes haploid (1n) 1 allele for every trait Pollen grains stigma style ovary 2 ovules

Pollination Benefits of animal pollination stigma style ovary 2 ovules 2) Style as “selective racetrack” So, fittest (fastest) pollen grains mate Pollen grains stigma style ovary 2 ovules

Pollination Evidence? Coyote melon: U.S. deserts Seeds from over-pollinated flowers produce more vigorous seedlings

Outcrossing Major benefit sexual reproduction is ___________ Enhanced by mating with others (outcrossing) How favor Outcrossing?

Outcrossing Favor outcrossing: 1) Dioecy

Outcrossing Favor outcrossing: 2) Floral morphology Heterostyly: Distyly and tristyly

Outcrossing Favor outcrossing: 3) Floral phenology Protandry: anthers dehisce first Protogyny: stigma becomes receptive first Protandry

Outcrossing Favor outcrossing: 4) Self-incompatibility: prevent germination self pollen or slow self pollen tube growth

Pollinator Specialization May be learned May be species-specific Monolecty: Flowers of 1 plant species visited Oligolecty: Flowers of few plant species visited Polylecty: Flowers of many plant species visited

Pollination syndromes Disclaimer: We make broad generalizations and exceptions exist to most statements!

Pollination syndromes Bee pollination Bees: intelligent, agile good eyesight (including UV light) good smellers day-active Halictid bee Leafcutter bee Bumble bee

Pollination syndromes Bee flowers: Colorful (not red) Landing platform: where bee lands on flower Often nectar guides: patterns help bee orient Petals in visible light (top) and UV (bottom)

Pollination syndromes Moth pollination Moths: Poor vision (nocturnal) Excellent smellers Long coiled tongue Some (hawkmoths) hover

Pollination syndromes Moth pollination Moth-pollinated flowers Open night Sweet fragrance White/light colored Nectar in tube Nectar spur story

Pollination syndromes Angraecum orchid (Madagascar) Nectar spur almost 1 foot long!

Pollination syndromes Angraecum orchid from Madagascar. Nectar spur almost 1 foot long! Tongue…

Pollination syndromes Tongue Magazine, Gene Simmons fans. Family Guy: “Kiss saves Santa” Gene Simmons from KISS

Biotic Pollination Mutualism: (+,+) interaction Do cheaters prosper?? Sometimes…..

Pollination syndromes Flesh fly pollination Lay eggs in meat

Pollination syndromes Some fly-pollinated flowers No reward: flies fooled. Stapelia flower

Pollination syndromes Sexual mimics: Males attempt to mate (pseudocopulation) No reward supplied A male wasp “mating” with an Ophrys flower (how embarrassing...)

Pollination syndromes Another trick flower Grass pink orchid (Calopogon): pitcher plant bogs SE US Fake stamens on labellum Cattleya orchid (flower made right side up) Calopogon orchid (flower made upside down!)

Biotic Pollination Do cheaters prosper?? Floral robbers! Cool robbers…

Biotic Pollination Floral Robber: Remove rewards (nectar, pollen) but do not pollinate Ex, snapdragon Is robbing bad for plant?

Biotic Pollination Do cheaters prosper?? Yucca moth story Yucca: Agave family Ex, Yucca filamentosa

Biotic Pollination Pollination by yucca moth: Behavior Question: What do you call a female yucca moth?

Biotic Pollination Question: What do you call a female yucca moth? A pistil-packing momma………. Granny Glock

Biotic Pollination What if moth cheats (lays too many eggs?)