Lecture 26 Flashcards
pollination
plant sex
Movement of pollen from anthers (male parts) to stigma (female parts)
how is pollination accomplished? (self-pollination)
Pollen tubes grow into stigma to fertilize ovaries
Pollen goes to stigma, travels down style to reach the ovary
what kind of pollination do blueberries rely on?
insect pollination
self-pollination
pollen movement within plant
cross-pollination
pollen movement b/w plants
what form of pollination maintains genetic diversity?
cross-pollination
is cross-pollination only accomplished by insects?
no
why is wind a disadvantageous mechanism of cross-pollination?
there’s no direction of the wind so plants need to produce a lot more pollen
______ of all flowering species are animal pollinated (mostly by insects)
87.5%
how do insects know what flowers to pick to pollinate?
Many insects have floral constancy where they pick the same species of flower
_____of food we eat comes from crops that benefit from insect pollination
~35%
Insect pollination _______ the yield
increases
what type of plant commenced insect pollination?
angiosperms
early pollinators included what insects?
beetles & thrips
what is an ex of a plant & insect spp that underwent coevolution?
bees & eudicots
About _______ years ago bees originated which about the same time ______ diversified
100 million
angiosperms
how many bee spp have been described?
20,000
what characteristic of bees enables humans to farm them? how is this accomplished?
highly social
create artificial cavities for bees to nest
most bees are solitary, meaning that ____
most bees don’t produce honey
what type of development do bees have?
holometabolous
describe the lifecycle of bees
Egg –> larvae consumes nectar –> pupae –> adult
why do bees eat pollen?
to acquire PRO in order to develop eggs
pollination syndrome
match morphology of the pollinator to attract pollinators
how do insects respond to pollination syndrome?
Insects have floral consistency & visit the same spp
what is an ex of floral signal convergence (pollination syndrome) across 3 diff insect & plant spp?
hummingbird – red with deep tubes
Blue pink flowers release a chemical to attract bumble bees
white flowers that release a chemical to attract moths
how does an orchid accomplish insect pollination?
Orchid will produce a chemical equivalent to a female pheromone of a wasp or bee & the flower appears like a bee
Male will try to mate with flower & p/u pollen
how do plants attract flies for pollination?
mimic oviposition sites by releasing the smell of dead meat
what did Darwin predict about the plant A. sesquipedale ?
has very long tubes where nectar is produced
predicted a wasp with a very long tongue drank the nectar
this moth was later found
how does D. floribunda attract insects?
produces flower oils produced by bees used for offspring
Bee has unusually long front legs to access the oils
how does the Nolana blossom in Chile attract insects?
bees nest in dead plants
describe the process of how figs are pollinated by wasps
Female has pollen on her, finds immature fig, enters a special hole where there are fig flowers
Lays eggs in fig flowers & pollinates plant
Some of flowers with pollen will develop into galls
Males will emerge & mate with females in other flowers
Males will make a tunnel
Females will p/u pollen & leave trough tunnels
Males & mothers die inside the plant
what type of evolution is seen in the relationship b/w the fig & the wasp?
coevolution
Monolecty
one pollinator visits one plant species (rare)
Oligolecty
one pollinator visits several related plant species (common)
Polylecty
one pollinator visits many unrelated plant species (common)
what form of specialization is rare?
monolecty
what are the 3 forms of specialization?
monolecty
oligolecty
polylecty
what are the factors resulting in the decline of bee pops?
Varoa mites – only attacks honey bees
Pesticides
Bacterial, viral & fungal infections
Habitat loss – largest factor
what is a solution to bee declines?
providing pollinator habitats for bees
More visits to crops where pollinator habitats were present
providing pollinator habitats for bees resulted in a ____ incres in yield over ____ years
20%
4 years
how can you support pollinators?
Feed them
Native plants preferred
House them – nest
Nest in ground or holes (can make artificial ones)
Don’t kill them (no insecticides)
Use integrated pest management approach
what % of nesting bees nest in the ground?
70%
what benefits does gardening have on bees? (5)
Support biodiversity
Help slow bee declines
Enjoy wildlife in your own yard
Education
Pollination for fruits
what pollinator is used in commercial greenhouses & why?
bumble bees
for their buzz pollination (blueberries, tomatoes etc.)
why are Orchid bees attracted to their plants?
males visit plants, collect various chemicals of scents to attract females
