Grevilla+Robyn+Gorden

Living systems Prac 9 Sex, rewards and pollination

Group members: Sasha Clarke-Rowlands, Tram, Stacey, Jeneigh & Natalie

Plant Species: Grevillea "Robyn Gordon". Named in1969 by it cultivar Mr David Gordon in memory of his daughter who died in 1969, aged 16.

Common name: Robyn Gordon

Distribution: this is not a naturally occurring species. It was the first mass produced Grevillea hybrid. Was first cultivated in 1963 by accident, when Grevillea banksii crossed with Western Australian species Grevilla bipinnatifida in the garden of Grevillea collector David Gorden. Then result was a hybrid that was distributed in March 1968 to some nurseryman before being later made commercially available. Registered in 1973 it is similar to "Superb" cultivar which has the same parentage. Famous gardener Don Burke was pivotal in convincing David Gorden to distribute this plant and number of others her later cultivated.

Habit: Robyn Gordon is a short evergreen shrub which grows to between 45-60 high. It is a very drought torrent, hardy plant plant. It will grow in a wide range of climates and soils but prefer well drained soils and semi shade to full sun.

Inflorescence: There are an average of 66 pisti per inflorescence. Average length of pisti is age dependent (Fig1.1). Pollen Presenter at 10x magnification

Flowers It blooms all years round, and was cultivated because of it very large and numerous red flowers that change as the pisti open (fig 1.2).

The flowers a very attractive to pollinators including insects like bees and butterflies, mammals such as possums and in particular a while range of honey/nectar eating bird. However due to the shape of the flowers and the high of the pollen presenter insects are nectar thieves while the larger animals are pollinators as the brush against the presenter as they collect the nectar.

The average sucrose percentage in the nectar of the pisti is 71%, almost pure sugar and very attractive to animals for its high simple sugar levels. Pollen Pollen is large triangular and yellow in shape,with straight edges surrounded by irregular flange. they have wort like verrucate surfaces They are located on the curve of the floral segment. Fruit This plant has no fruit as it in infertile. Seed: This plant never set seeds, all propagation has been by vegetative means. It pollen is less an 1% fertile (while the parent species are more than 95%)

Pollen at 10x magnification