Lab 5: Plant-Insect interactions: Pollination

What are the three major plant parts?

1. Perianth = sepals + petals

2. Androecium = male parts (filaments + anther = stamen)

3. Gynoecium = female parts (stigma + style + ovary = carpel//pistil)

What is the difference between bisexual and unisexual flowers?

Bi = has both male and female parts = perfect

Uni = only has either male or female parts = imperfect

How is pollination specially evolved?

To encourage visitors by pollinators; this is though scent, rewards, shelter and more.

What is pollination?

The process by which pollen grain are transported to receptive carepel of the flower for fertilization

What are a few pollination systems?

• Wind

• Water

• Animal

What are two kinds of coevolution?

1. Antagonistic

2. Mutualistc

What do bee pollinated flowers look like?

• Blue or yellow with a fragrant odour

• Nectar guides

• Large nectaries

• Landing platforms

What do lepidopteran pollinated flowers look like?

• Brightly coloured (especially for butterflies)

• Large nectaries

• Elongated corolla

• Fragrant odour

What do beetle and fly pollinated flowers look like?

• Dull coloured

• Fruity, musty or rancid odour

What is eusociality?

An system of organization that involves the cooperation among individuals in each generation. This results in the division of labour and formation of castes

What are the castes of bees like?

There are two castes

1. Workers = nurses, housekeepers, guards, foragers and scouts

2. Reproductive = queens and drones

What does haplodiploidy look like in bees?

Fertilized eggs produce female queens and workers

Unfertilized eggs produce male drones

T/F queens have the same food source as workers and drones?

False

They eat royal jelly and workers consume bee bread

How does the queen communicate with the wokers?

Using queen mandibular pheromone (QMP)

It concentration is correlated to fertility; when it is low the workers produce new queen cells

How is cell size linked to bee caste?

Small size = workers

Large = queen and drone

What are the two main forms of communication with bee dancing?

1. round dance = <50 m

2. waggle dance = >150 m

How does dancing convey information between bee workers?

• Angle = upward distance to R or L

• Tempo and duration of buzzing = distance to food source

• Information about resource = taste and smell

What percent of Canadian honey is produced in Alberta?

40%

4 million flower visits = 1kg of honey — 40 trillion flower visits

What are the four key honey bee diseases?

1. Nosema disease (microsporidia)

2. Foulbrood (bacteria)

3. Parasitic mites

4. Colony collapse disorder

What are the two species that cause Nosema disease?

1. Nosema apis

2. Nosema ceranae (recently detected in Alberta in 2007)

What does Nosema disease do?

It impairs digestive process causing premature aging and death of worker bees

It spreads through spores in bee feces

In queen bees it causes the degeneration of ovaries

What are the two kinds of mites in Canadain bees?

1. Varroa mite = Varroa destructor

2. Tracheal mite = Acarapis woodi

What do parasitic mites do to bees?

They feed on haemolymph of larvae and or adult bees

—> This causes weight loss, abnormal developement and even death

What are the main foulbrood diseases?

1. American foulbrood causes by Paenibacillus larvae

2. European foulbrood causes by Melissococcus pluton

3. Chalkbrood

4. Sacbrood

Which is the most severe foulbrood disease?

American foulbrood

How does American foulbrood impact bees?

The bacteria spread when the larvae ingest the spores

Toxins released by the bacteria kill the larvae

T/F We don’t know the cause of Colony Collapse disorder?

True

There are many theories as to what causes it

What happens to the bees in colony collapse disorder?

The bees leaves their hives and never come back

What groups do honeybees belong to?

Apis mellifera

Hymenoptera: Apiadae

What group do Bumble bees belong to?

Bombus impatiens (E) and B. occidentalis (W)

Hymenoptera; Apidae

What is the key differentiation of bumble bees from honey bees?

BB nest in the ground and have annual conolies

Only the fertilized queen overwinters

They don’t use honey combs but cups

What is buzz pollination?

Also called sonication

They grasp onto the flower and make rapid wing movemnts which shakes the flower and dislodges the pollin

T/F Bumble bees are the most used in greenhouses?

True

They are really good pollinators but very cheap

What is a unique bumble bee disease not shared with honey bees?

Trypanosome parasite crithidia bombi

What are the two bumble bee parasites we discus?

1. Cuckoo bumble bee (Psithyrus species)

2. American wax moth

What species of fungi causes nosema disease in bumblebees?

Nosema bombi

How do cuckoo bumble bees infiltrate the bee colony?

They kill the founding queen and usurpes the workers to feed her and her offspring

What groups do leaf cutter bees belong to?

Mehachile rotunda

Hymenoptera: Megachilidae

What are the characteristics of leaf cutter bees

• solitary bees

• Females nest in small cavities; cut leaves and petals to make cells

• Use haplodiploidy

• Use trip pollination

What is trip pollination?

Relases the stamen / stigma from keel petals

What is an agricultural application of leaf cutterbees?

Use for Canadian Alfalfa seed production

They use trip pollination; very effective pollinators of this crop

Need alternate crops to make cells

What are the two main leafcutter bee diseases?

1. Parasitoid wasp = Pteromalus venustus

2. Chalkbrood = Ascosphaera aggregate

How does Chalkbrood affect leafcutter bees?

Turns the developing larvae into a mummary