Purple+12


 * Pollination, Sex and Rewards**

Group: Purple 12

Group Members : Mackenzie Foord Lachlan Pettit Leah Miller Lock Art Zahar

Plant species : //Rhododendron x// 'George Tabor' Plant family : //Ericaceae// Common name : George Tabor Azalea

Originates in Japan, China and Korea. Leaves and nectar highly toxic. They contain cardiac glycosides and grayanotoxins. Both compounds affect sodium compounds on cell membranes. Floral formation ; 5 petals, 1 carpel consisting of stigma, style and ovary, 9 stamens consisting of anther and filaments. Possible pollinating agent : Bees and birds ( the landing site is clearly seen on the flower)

Figure 1 : Flower under UV light The insides of the flower are more fluorescent to attract insects.

__Floral Morphology__ Vernier calipers were used to measure the metrics of the sample of flowers. Sepal to petal tip was measured for height, the widest point, petal to petal was measured for flower width. After measuring the distance between stamen and carpel, each was removed and the length was measured. There seemed to be a fair amount of consistency throughout the measurements.

Measuring the flower

Figure 2 : Measuring the width of inflorescence with vernier caliper

Figure 3 : Measuring the height of inflorescence from sepal to petal using vernier calipers.



Figure 3 : Measuring the height of carpel using vernier calipers.

Figure 5 : Transverse section of the flower showing reproductive organs



Figure 6 : The reproductive structure of the flower


 * Table 1 :Average (mm) and +/- SD measurements of azalea flower structure conducted with vernier calipers ||
 * Sample || Height of Inflorescence- Sepal Base to Petal tip || Width of Inflorescence || Height of Carpel || Height of Stamen || Distance between Carpel and Stamen ||
 * 1 || 40.8 || 56.0 || 41.2 || 24.1 || 19.9 ||
 * 2 || 42.7 || 58.9 || 45.8 || 27.0 || 17.2 ||
 * 3 || 46.0 || 57.9 || 45.0 || 26.3 || 14.4 ||
 * 4 || 38.8 || 52.0 || 45.1 || 26.1 || 18.3 ||
 * 5 || 36.0 || 42.9 || 38.1 || 19.0 || 16.8 ||
 * Mean || 40.9 || 53.5 || 43.0 || 24.5 || 17.3 ||
 * SD || 3.8 || 6.5 || 3.3 || 3.3 || 2.0 ||
 * Mean || 40.9 || 53.5 || 43.0 || 24.5 || 17.3 ||
 * SD || 3.8 || 6.5 || 3.3 || 3.3 || 2.0 ||
 * SD || 3.8 || 6.5 || 3.3 || 3.3 || 2.0 ||

__Pollination__

The main animal vectors aiding pollination would be insects, usually bees and moths. As the flower fluoresces heavily under UV light this is an indication that insects are a main pollinator. Insect see well in the ultra violet spectrum, and many flowers advertise the availability of nectar and or pollen by having parts of the flower such as the petals showing at this wavelength. Interestingly, it was noted that the distance from stamen to carpel was perhaps too large for an insect pollinator. The filament however was the most prominent illuminated part of the flower under UV light and it is thought that this could be the main guide for insects which would brush past on their way to their nectar reward. The second possible vector is that of a bird or small mammal, due to the larger distance between carpel and stamens.

__Pollen:__ Figure 7 : Pollen stained with fuchsin gelatin (40x) Figure 8 : Pollen stained with fuchsin gelatin (100x)
 * Dense clusters of pollen grains, roughly 1000 per anther
 * Each pollen grain looks as though it is made up of 3 closely packed globules

__Nectar__

An attempt to extract nectar was made using glass capillary tubes, however no discernable amount of nectar collection was possible even combining nectar from multiple flowers. It is thought that the abundance of pollen may be the main attractant for bees, or perhaps the nectar quality is high. Unfortunately there was not enough nectar collected to be able to use the refractometer.