Team+Awesome+-+Azalea

Thuy Katherine Lydia Ashley Shirley
 * Group members:**

Plant species: most likely Kurume azaleas Genus: Rhododendron Family: Ericacae

Figure 1: Azalea Azaleas have small showy flowers and this species has more than one individual flower (normally three) attached to each sepal. They are hermaphrodites as they have both male and female reproductive organs.


 * Pollination and Fertilisation**

Vector-pollinated flowers are bright coloured, curious shapes, scented, and contain nectar and plenty of pollen to attract insects and birds. These pollen carriers (vectors) inadvertently get excess pollen on them which wipes off onto the broad, grooved, sticky stigmas of other flowers they visit. Many flowers have the arrangement of floral parts to prevent self-fertilisation.

The azalea is a vector-pollinated flower as it has bright coloured petals. It is mostly pollinated by insects, particularly bees. The bees inadvertently get excess pollen which gets wiped off onto the sticky stigmas of the other flowers they land on. The stigma of the flower is longer than the stamen, preventing self-fertilisation. After the bees have transferred the pollen on to a compatible stigma, the pollen tube will gradually grow so that the egg cell in the embryo sac can be fertilised.

Figure 2: Germinating pollen grain []

During this process, the generative nucleus divides by mitosis to produce 2 male haploid gametes. The pollen tube enters the ovule through the micropyle and penetrates the embryo sac wall. The tip of the tube bursts open and double fertilisation occurs as shown in the following diagram. 1 male gamete fuses with the egg cell to produce a diploid zygote. (2n) 1 male gamete fuses with both the polar nuclei to produce the triploid primary endosperm nucleus. (3n)



Figure 3: Fertilisation and double fertilisation Source: Living Systems lectures


 * Floral Morphology and visitations:**

Figure 4: Flower under UV light. The insides of the flower are more fluorescent to attract insects especially bees.

Table 1: Lengths of Azalea structures Group of 2-3 flowers are held together with one sepal at 120 degrees. Figure 5: Using a vernier caliper to measure floral structures
 * Variability of floral morphology:**
 * Height of inflorescence (sepal base to petal tip) || 38 mm ||
 * Width of inflorescence || 41mm ||
 * height of carpel || 31.8mm ||
 * Height of stamen || 25mm ||
 * Height of ovary || 3.8mm ||
 * Distance between carpel and stamen || 1mm ||

Figure 6: Pollen under the light microscope (40x) lengthL 200.0um
 * Pollen morphology:**


 * Nectar characterisation**

There was no nectar found in the azalea. This may be due to the season or time when the flower was collected.