2.19 Nectary Guides Flashcards
What are Nectary Guides?
Patterns on the petals pointing to the inside of a flower
Usually at the blue and yellow end of the visible spectrum, many only visible under UV light
Five ways flowers communicate to bees that they are ready to provide pollen/nectar
ACNTT
*Aroma - The bees’ sense of smell is better than their vision and will detect flowers from further away.
*Colour - Bees have poor vision at the red end of the spectrum but are sensitive to UV light
*Nectary Guides - many flowers have veins along the petals which show up in the near UV to guide the bees to the nectaries.
*Texture - the texture of the petals may influence the readiness of bees to land
*Taste - higher sugar contents will be more attractive to bees and will encourage them to visit similar flowers.
All five are liable to change once the flower has been fertilised signalling to the bees that their services are no longer required.
Nectary Guides - Forget-me-not
Tiny flowers are bee blue in colour and have a yellow corona at the centre.
This attracts the bees to the centre of the flower.
Once the flower has been pollinated and matures the central yellow corona fades to white.
Nectary Guides - Horse Chestnut
Not all the flowers in a spike open at once so that the flowering period is prolonged.
Once a flower has been pollinated, its colour changes from yellow to red as a warning to visiting bees not to bother with it!
Nectary Guides - Red clover
Florets wither and drop after pollination
Nectary Guides - why?
• Bees have poor vision at the red end of the spectrum but are sensitive to Ultra Violet (UV) light.
Many flowers have veins along the petals which show up in the near UV andact as a guide to direct the bees to the nectaries.
• Honey bees are loyal to a particular plant species and the pattern of the nectar guides helps them move quickly from one plant to the next.
• It also helps with efficient cross pollination of the nectar providing plant.
