Seeds of South Australia
Cardamine gunnii (Cruciferae)
Spade-leaved Bitter-cress
List of species for Cardamine
Display more images
Click on an image to enlarge it
Seed collecting:
September to November
Herbarium region:
South Eastern
NRM region:
South East
IBRA region
Glenelg Plain (NCP02)Naracoorte Coastal Plain
 Endangered   (IUCN: EN B2ab(i,ii,iii,iv))   (Probable Decline)   [highly localised, Marshes & Topperwein, could be gone from Marshes]
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 Cardamine]
Name derivation:
Cardamine from the Greek 'kardamon' a name given by Dioscorides for a species of cress, an Indian spice and derived from the Greek 'cardia' meaning heart and 'damaein' meaning to blind, alluding to the reputed heart-strengthening effects of the plant. Gunnii named after Ronald Campbell Gunn (1808-1881), a British botanist and legislator in Launceston, Tasmania.
Distribution:
Found in the lower South-east in South Australia, growing in moist habitats. Currently  known only from one Native Forest Reserve in lowland redgum swamps. Was also known from Victoria and Tasmania but assumed extinct in those states.
Status:
Native. Very rare in South Australia. Presumed extinct in the other States.
Plant description:
A small weak annual herb to 25 cm high arising from a thick, tuberous perennial tubestock. It has a basal rosette of discolourous lobed leaves and an erect stem of small white flowers. Flowering between August and September.
Fruit type:
Long pale brown pods to 5 cm in length, splitting into two.
Seed type:
Small yellow flat reniform seeds to 1.5 mm long and 1 mm wide.
Embryo type:
Bent.
Seed collecting:
Collect maturing pods those turning pale brown with yellow seeds inside. Be gentle with the pods as they split open easily.
Seed cleaning:
Place the pods in a tray and cover with paper to prevent seeds from popping out and leave to dry for a week. Then rub the dried pods gently by hand 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 two collections, the seed viability was average to high, ranging from 75% to 100%.
Seed germination:
This species has physiological dormancy that need to be overcome for the seed to germinate.
Seeds stored:
LocationNo. of seeds
(weight grams)
Number
of plants
Date
collected
Collection number
Collection location
Date
stored
% ViabilityStorage
temperature
BGA 
MSB
2750 (0.5 g)
2750 (0.5 g)
50+28-Oct-2008DJD1187
South Eastern
20-Jul-2009100%+5°C, -18°C
DJD15511-Jan-2012-18°C
BGA2500 (0.448 g)30+28-Sep-2013DJD2237
South Eastern
24-Mar-201575%+5°C, -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
May-0976%21 d63 d
1% agar with 100 mg/L potassium nitrate;
/ 8 weeks spring/autumn, 5 weeks winter
May-1070%7 d33 d
1% agar with 250 mg/L gibberellic acid (pH 6.5);
Incubated under winter conditions
May-1026%11 dNA
1% agar with 100 mg/L potassium nitrate;
Incubated under winter conditions
May-0920%63 dNA
1% agar;
/ 7 weeks spring/autumn, 3 weeks winter
May-1012%11 dNA
1% agar;
Incubated under winter conditions
May-1010%15 dNA
1% agar with 100 mg/L potassium nitrate;
Incubated under spring/autumn conditions
May-1010%15 dNA
1% agar with 250 mg/L gibberellic acid (pH 6.5);
Incubated under spring/autumn conditions
May-100%NANA
1% 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)