Lecture 32

Question 1

aphids have 2 ovaries, each consisting of___ ovarioles

Answer 1

7

Question 2

T/F - ovaries contain eggs & embryos

Answer 2

F - only eggs

Question 3

how do aphids feed on plants?

Answer 3

feed on plant sap by inserting their sucking mouthparts into the tissues

Question 4

what does sap contain a lot of?

Answer 4

carbs & water

Question 5

how do aphids acquire a sufficient amount of PRO from sap?

Answer 5

Passes a lot of carb out with water to get enough PRO

When the plant is growing, it is immobilizing AAs

Question 6

rostrum

Answer 6

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

Question 7

Maxillary stylets are connected to the ________ _______& _________ _________

Answer 7

food canal

salivary duct

Question 8

what protective role does saliva have for aphids?

Answer 8

protect the stylet when the mouthparts are emerged into the plant

Question 9

T/F - aphids are always green

Answer 9

F

Question 10

what is the role of the white material on the outside of the wooly aphid’s body?

Answer 10

secretes white wax to protect its body from predators & retain moisture

Question 11

how many spp of aphids are in MB?

Answer 11

324

Question 12

describe the lifecycle of aphids during the spring & summer

Answer 12

only female

parthenogenesis reproduction - asexual, mitosis & 2n

viviparous (live birth)

not cold-hardy

Question 13

describe the lifecycle of aphids during the fall & winter

Answer 13

sexually produce eggs - meiosis (n)

cold hardy eggs produced

Question 14

describe the autoecious lifecycle

Answer 14

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

Question 15

describe the heteroecious lifecycle

Answer 15

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

Question 16

_____ ______ is the same for autoecious & heteroecious

Answer 16

wing production

Question 17

autoecious

Answer 17

single host

Question 18

heteroecious

Answer 18

2 hosts

Question 19

what are the factors stimulating wing production? (6)

Answer 19

Time interval
•	Crowding
•	Host deterioration 
•	Predators
•	Photoperiod (& temp)
•	Maleness

Question 20

it is believed that early aphids had what type of lifecycle?

Answer 20

heteroecious

Question 21

why do aphids move to the herbaceous host?

Answer 21

incres pop size

acquire AAs to facilitate the growth of the pop

Question 22

why is a woody host required?

Answer 22

needs to be close to material it can feed on in the spring

Question 23

Anholocyclic

Answer 23

a type of lifecycle where there isn’t sexual reproduction

lost the need to have sexual reproduction

Question 24

what does it mean when the aphids change colour?

Answer 24

males are a diff colour, indicates that the pop switched to sexual reproduction

Question 25

Describe the lifecycle of Uroleucon rudbeckiae on tall coneflowers

Answer 25

autoecious

8-10 days from birth –> adulthood

up to 10 young/day for 10 days

Question 26

how do aphids have a high reproductive capacity?

Answer 26

Parthenogenesis + live birth (rapid) = telescoping of gens

large embryos have 3 embryos within them

Question 27

what are the predators of aphids? (10)

Answer 27

lady beetle

hover fly

midge

lacewing

parasitoid wasp

digger wasp

mite

spider

birds

moose

Question 28

how do hover flies harm aphids?

Answer 28

hover flies feed on nectar & if they see the aphids they lay their eggs there. That way their larvae have a food source

Question 29

what does it mean if you see bare patches in your aphid colony?

Answer 29

hover fly larvae feeding

Question 30

how do midges harm aphids?

Answer 30

Insert digestive enzymes into the aphid & then suck out the materials

Question 31

what does it mean if you see aphid corpses?

Answer 31

midge have ate the aphids

Question 32

when do lacewings feed on aphids?

Answer 32

larvae & adults

Question 33

what does it mean if an aphid is changing colour?

Answer 33

have been parasitized by a parasitoid wasp

Question 34

how do digger wasps harm aphids?

Answer 34

adults collect to feed to offspring

Sting to paralyze them (not dead)

Store them in a cell

Lay an egg in the cell

Question 35

how do moose harm aphids?

Answer 35

eat the flowers where aphids lay their eggs

Question 36

why is it important to study aphids? (4)

Answer 36

To understand crop pests better

To understand pop dynamics better

To understand predation better

To satisfy curiosity