Seeds of South Australia
Swainsona dictyocarpa (Leguminosae)
Coondambo pea
List of species for Swainsona
Display more images
Click on an image to enlarge it
Seed collecting:
October to November
Herbarium region:
Gairdner-Torrens
NRM region:
South Australian Arid Lands
IBRA region
Kingoonya (GAW05)Gawler
 Endangered   (IUCN: EN B2ab(i,ii,iii))   (Definite Decline)   [needs EPBC nomination, no recent records, endemic to SA]
RSCA map:
Regional Species Conservation Assessments per IBRA subregion. Please click the thumbnail map.
AVH map:
Australian distribution map (external link)
SA Census:
Census of South Australian plants (external link)     [genus Swainsona]
Name derivation:
Swainsona named after Isaac Swainson (1746-1812), an English scientist and horticulturalist who had a private botanic garden near London. Dictyocarpa from the Greek 'dictyon' meaning network and 'carpos' meaning fruit; referring to the net-like veins on the fruit.
Distribution:
Endemic to South Australia and found only in a restricted area near Bitter Well, Coondambo in red sandy plain.
Status:
Native. Very rare in South Australia.
Plant description:
Small erect or ascending herb  to 15cm tall with several smooth stems arising from a taproot. Leaves 2-4 cm long with 3-7 leaflets. Flower purple.
Fruit type:
Dark brown papery pod 10-15mm long, smooth with a raised reticulate pattern on the surface.
Seed type:
Light brown to orange, semi-flat reniform seeds to 3mm long with a wrinkled surface.
Embryo type:
Bent.
Seed collecting:
Collect mature pods, those turning brown and contain hard seeds. Mature pods can be found lying on the ground next to the plant.
Seed cleaning:
Place the pods in a tray and leave to dry for a week. When dried the pods can become hard and difficult to open. Use a rubber bung to rub the pods or break the pods open with your fingers to dislodge the seeds. Use a sieve to separate the unwanted material. Store the seeds with a desiccant such as dried silica beads or dry rice, in an air tight container in a cool and dry place
Seed viability:
From one collection, the seed viability was high, at 80%.
Seed germination:
This species has physical dormancy that need to be overcome for the seed to germinate (e.g. nicking or softening the seed coat).
Seeds stored:
LocationNo. of seeds
(weight grams)
Number
of plants
Date
collected
Collection number
Collection location
Date
stored
% ViabilityStorage
temperature
BGA 
MSB
13500 (34.7 g)
6200 (16 g)
200+4-Oct-2010DJD1930
Gairdner-Torrens
1-Jan-201280%-18°C
Location: BGA — the seeds are stored at the Adelaide Botanic Gardens, MSB — the seeds are stored at the Millennium Seed Bank, Kew, England.
Number of plants: This is the number of plants from which the seeds were collected.
Collection location: The Herbarium of South Australia's region name.
% Viability: Percentage of filled healthy seeds determined by a cut test or x-ray.
Germination table:
DateResultT0T50Pre-treatment | Germination medium | Incubator: Photoperiod / Thermoperiod
April 201198%5d5d Seed coat nicked
70mm glass petri dishes on 1% w/v agar
Incubated under spring/autumn conditions
Result: Maximum percentage of germination observed.
T0: Number of days before first germinant observed.
T50: Number of days to achieve 50% germination.
Pre-treatment: The initial treatment that the seeds received prior to placement on germination media.
Germination medium: The substrate that seeds were placed on for the duration of the germination experiment.
Incubator conditions:
Photoperiod: The duration of light exposure that the seeds were subject to during a 24 hour period.
Thermoperiod: The constant or diurnal temperatures that seeds were subject to during a 24 hour period.
Winter conditions: 15°C 20 h (3am→11pm); 5°C 4 h (11pm→3am) / 10 h light (8am→6pm); 14 h dark (6pm→8am)
Spring/Autumn conditions: 22°C 12 h (8am→8pm); 10°C 12 h (8pm→8am) / 12 h light (8am→8pm); 12 h dark (8pm→8am)
Summer conditions: 30°C 14 h (6am→8pm); 15°C 10 h (8pm→6am) / 14 h light (6am→8pm); 10 h dark (8pm→6am)