Agriculture Reference
In-Depth Information
he collected many new plant specimens and gave them to Kew Gardens on his re-
turn from the expeditions (Gilbert
1966
; Kew
2012
).
Sourcing new forms of plants for commercialisation can be achieved either from
plant selection from natural populations or by direct breeding.
Surveying natural populations
In the first instance sourcing variation involves
surveying natural populations to find different and unusual plants that are of inter-
est to the ardent collector, botanist and nursery person for commercialisation. A
rich diversity of plant species occurs around the world for instance. The Australian
floral kingdoms contain 19,324 species that include flowering plants (18,706), fern
and allies (498) and gymnosperms (120) (Chapman
2009
) Significant designated
biosphere reserves around the world now contain much of this diversity. Such plant
material can be found in the south west of Western Australia, the tropical rainforests
of North Queensland, South Africa's fynbos, the tropical rainforests of the Amazon
basin in South America, and in California, USA. For example The Fitzgerald River
National and Park Biosphere Reserve (Moore et al.
2001
), on the south coast of
Western Australia covers 329,039 ha and comprises only 0.2 % of Western Austra-
lia's land surface, but contains over 20 % of that State's plant species. This includes
nearly 1,800 species of flowering plants, and some 75 plant species and offers
a rich diversity of plants such as
Banksia
spp
.
, bottlebrush (
Callistemon
spp
.
),
feather flowers (
Verticordia
spp
.
), and the unique Qualup bell (
Pimelea physodes
).
Similarly a rich diversity of plants exists in the Cape Biosphere Reserve north of
Cape Town in South Africa and includes the fynbos. This park is 378,240 ha in size
and includes ca. 8,900 flowering plant species, some 6,000 being endemic to the
region. It includes a number of plants that have developed under harsh conditions
such as Sea Guarrie (
Euclea racemosa
), Cape Hyacinths (
Lachenaliai
bulbifera
),
Aspalathus callosa
and the Cape reed (
Restionaceae
). Cape heaths include the
white to mauve
Erica caffra
, the red to pink
E. mammosa
and the red
E. coccinea
,
as well as
Proteas,
Leucospermums
and
Serrurias
such as
P. repens
,
P. cynaroides,
Leucospermum conocarpodendron
and
Serrurias trilopha
that offer exciting pos-
sibilities for selection and domestication (Goldblatt and Manning
2000
; UNESCO
2005
).
Surveying natural populations involves a number of steps including locating
populations, surveying the extent of variation, the collection and propagation of ma-
terial, and evaluating the plants' performance in a cultivated environment. Locating
populations can be done through existing databases that provide historical records
of where specimens have been collected and preserved as herbarium voucher speci-
mens. In Western Australia these records and some specimens date back over 100
years. Not always but often, these records have been updated by more recent sur-
veys or from information from collectors or bush pickers. The next task is to select
from these records a location for a species, obtaining appropriate licences and visit
sites. This can be a frustrating process as often for such old sites the original flora
have long since disappeared through settlement, disturbance or herbivore and weed
infestation. Frequent visits are often necessary as different flora may dominate in
different seasons. It is usually best to visit the site during the predicted flowering
season for a particular flower. There is also the question of phases of dominance
