Lecture 32 Flashcards
aphids have 2 ovaries, each consisting of___ ovarioles
7
T/F - ovaries contain eggs & embryos
F - only eggs
how do aphids feed on plants?
feed on plant sap by inserting their sucking mouthparts into the tissues
what does sap contain a lot of?
carbs & water
how do aphids acquire a sufficient amount of PRO from sap?
Passes a lot of carb out with water to get enough PRO
When the plant is growing, it is immobilizing AAs
rostrum
highly modified labium
Contains a channel/gutter into which 4 stylets are fitted
2 pairs of stylets
Mandibular styles – to the side & tooth-like
Maxillary styles
Maxillary stylets are connected to the ________ _______& _________ _________
food canal
salivary duct
what protective role does saliva have for aphids?
protect the stylet when the mouthparts are emerged into the plant
T/F - aphids are always green
F
what is the role of the white material on the outside of the wooly aphid’s body?
secretes white wax to protect its body from predators & retain moisture
how many spp of aphids are in MB?
324
describe the lifecycle of aphids during the spring & summer
only female
parthenogenesis reproduction - asexual, mitosis & 2n
viviparous (live birth)
not cold-hardy
describe the lifecycle of aphids during the fall & winter
sexually produce eggs - meiosis (n)
cold hardy eggs produced
describe the autoecious lifecycle
Egg hatches in the spring, all females
Reproduces parthenogenetically until late summer
Late summer, parthenogenetic females will produce males & females to mate
lay eggs that overwinter
can produce aphids with wings
describe the heteroecious lifecycle
2 hosts:
woody host (spindle) - primary
Herbaceous (bean etc.) - secondary
eggs hatch in the spring
acquire AAs from plant, until the plant’s leaves are expanded & is no longer growing (summer)
aphids produce a winged gen during late spring/early summer that moves to the herbaceous host
undergo parthenogenesis (can produce winged if necessary)
fall - produce winged gen that moves back to the woody host
females & males mate to produce a gen of egg laying females produced to lay cold hardy eggs to overwinter
_____ ______ is the same for autoecious & heteroecious
wing production
autoecious
single host
heteroecious
2 hosts
what are the factors stimulating wing production? (6)
Time interval • Crowding • Host deterioration • Predators • Photoperiod (& temp) • Maleness
it is believed that early aphids had what type of lifecycle?
heteroecious
why do aphids move to the herbaceous host?
incres pop size
acquire AAs to facilitate the growth of the pop
why is a woody host required?
needs to be close to material it can feed on in the spring
Anholocyclic
a type of lifecycle where there isn’t sexual reproduction
lost the need to have sexual reproduction
what does it mean when the aphids change colour?
males are a diff colour, indicates that the pop switched to sexual reproduction
Describe the lifecycle of Uroleucon rudbeckiae on tall coneflowers
autoecious
8-10 days from birth –> adulthood
up to 10 young/day for 10 days
how do aphids have a high reproductive capacity?
Parthenogenesis + live birth (rapid) = telescoping of gens
large embryos have 3 embryos within them
what are the predators of aphids? (10)
lady beetle
hover fly
midge
lacewing
parasitoid wasp
digger wasp
mite
spider
birds
moose
how do hover flies harm aphids?
hover flies feed on nectar & if they see the aphids they lay their eggs there. That way their larvae have a food source
what does it mean if you see bare patches in your aphid colony?
hover fly larvae feeding
how do midges harm aphids?
Insert digestive enzymes into the aphid & then suck out the materials
what does it mean if you see aphid corpses?
midge have ate the aphids
when do lacewings feed on aphids?
larvae & adults
what does it mean if an aphid is changing colour?
have been parasitized by a parasitoid wasp
how do digger wasps harm aphids?
adults collect to feed to offspring
Sting to paralyze them (not dead)
Store them in a cell
Lay an egg in the cell
how do moose harm aphids?
eat the flowers where aphids lay their eggs
why is it important to study aphids? (4)
To understand crop pests better
To understand pop dynamics better
To understand predation better
To satisfy curiosity
