Germination characteristics of flower species

Transcription

13 June 2011
ISTA GERMINATION SEMINAR
RITA ZECCHINELLI - ISTA FLOWER SEED TESTING COMMITTEE
Lu
ca
GERMINATION
CHARACTERISTICS
OF FLOWER SPECIES
Flower species in
the ISTA Rules:
 352 species
 192 genera
 55 families
13 June 2011
RITA ZECCHINELLI
DICOTYLEDON FAMILIES
Family
MONOCOTYLEDON FAMILIES
Family
N°genera
N°species
Amaryllidaceae
1
1
Asparagaceae
1
2
Asphodelaceae
1
1
Liliaceae
1
1
Poaceae
2
2
13 June 2011
N°genera
N°species
Acanthaceae
1
1
Aizoaceae
1
Amaranthaceae
N°genera
N°species
Hypericaceae
1
1
1
Iridaceae
1
1
3
6
Lamiaceae
14
21
Apiaceae
3
4
Linaceae
1
4
Apocynaceae
1
1
Malvaceae
6
7
Araliaceae
2
2
Nyctaginaceae
1
1
Asclepiadeaceae
1
1
Onograceae
2
4
Asteraceae
49
86
Papaveraceae
3
7
Balsaminaceae
1
2
Plumbaginaceae
4
8
Begoniaceae
1
2
Polemoniaceae
3
5
Boraginaceae
6
10
Polygonaceae
1
1
Brassicaceae
11
22
Portulaceae
1
1
Campanulaceae
3
13
Primulaceae
3
12
Capparidaceae
1
1
Proteaceae
1
1
Caryophyllaceae
6
16
Ranuncolaceae
7
20
Chenopodiaceae
1
1
Resedaceae
1
1
Cistaceae
1
1
Rosaceae
2
3
Convolvulaceae
2
5
Rutaceae
1
1
Crassulaceae
1
3
Saxifragaceae
1
1
Dipsacaceae
1
2
Scrophulariaceae
10
22
Fabaceae
4
8
Solanaceae
9
15
Gentianaceae
1
1
Tropaeolaceae
1
3
Geraniaceae
2
2
Valerianceae
1
1
Gesneriaceae
2
2
Verbenaceae
2
4
Hydrophyllaceae
3
4
Violaceae
1
3
Family
RITA ZECCHINELLI
What flower species have in common?
 ornamental use
 fast changing trends in the market
 for seed testing laboratories
- less experience in standardized methods
- lower number of samples/species
than for agricultural species and vegetable
- accreditation: all flower species in one crop group
13 June 2011
RITA ZECCHINELLI
GERMINATION METHODS IN THE ISTA RULES
Only one temperature for germination:
Agricultural species: 172 species/326 (53%)
Flower species: 35 species/352 (10%)
Three temperatures for germination:
Agricultural species: 18 species/326 (5,5%)
Flower species: 54 species/352 (15%)
Flower species:
higher variability within the species
lower degree of standardization
lower degree of knowledge and experience
13 June 2011
RITA ZECCHINELLI
SEEDLING EVALUATION ACCORDING TO GROUPS
(ISTA HANDBOOK ON SEEDLING EVALUATION)
Seedling Type
Seedling Group
A
A-1-1-1-1
Liliaceae
B
A-1-2-1-1
Asphodelaceae
C
A-1-2-2-1
Asparagaceae
D
A-1-2-3-1
Poaceae
A-1-1-1-1
Amaryllidaceae
A-2-1-1-1
Acanthaceae, Aizoaceae, Amaranthaceae, Apiaceae, Apocynaceae, Araliaceae,
Asclepiadeaceae, Asteraceae,
Asteraceae Begoniaceae, Boraginaceae, Brassicaceae, Campanulaceae,
Capparidaceae, Caryophyllaceae, Chenopodiaceae, Cistaceae, Convolvulaceae, Crassulaceae,
Dipsacaceae, Fabaceae (Galega, Mimosa), Gentianaceae, Geraniaceae, Gesneriaceae,
Hydrophyllaceae, Hypericaceae, Lamiaceae,
Lamiaceae Linaceae, Nyctaginaceae, Onograceae,
Papaveraceae, Plumbaginaceae, Polemoniaceae, Polygonaceae, Portulaceae, Primulaceae
(Anagallis, Primula), Proteaceae, Ranuncolaceae, Resedaceae, Rosaceae, Rutaceae,
Saxifragaceae, Scrophulariaceae, Solanaceae, Verbenaceae, Valerianceae, Violaceae
A-2-1-1-2
Balsaminaceae, Malvaceae
A-2-1-4-3
Primulaceae (Cyclamen
Cyclamen)
F
A-2-1-2-2
Fabaceae (Lupinus
Lupinus)
G
A-2-2-2-2
Fabaceae (Latyrus), Tropaeolaceae
E
13 June 2011
RITA ZECCHINELLI
Type C
Seedling Group A-1-2-2-1
Monocotyledons
Hypogeal germination
Epicotyl elongation
Primary root essential
A. densiflorus
The seedling part that grows towards the light
and turns green is the epicotyl
with the terminal bud
A. densiflorus
Asparagus spp.
(Asparagaceae)
A. setaceus
ISTA Germination methods
A. setaceus
13 June 2011
Substrate
Temperature
(°C)
TP; BP; S
2030; 20
Counts
First
(d)
Final
(d)
7-14
35
Breaking
dormancy
Soak in water
for 24 h
RITA ZECCHINELLI
Asparagus: development of the seedling during the test
•Start of germination: the primary root pierces the seed coat, followed by a short hypocotyl
and the basal part of the cotyledons (the upper part remains in the seed coat and absorbs
reserves from the endosperm)
- A. setaceus: has a very stout primary root;
secondary roots don’t normally develop (A)
- A. densiflorus: secondary roots normally develop;
one of them serves as a water storage organ (B)
terminal
bud
•The epicotyl emerges from the basal part of the cotyledon;
it bears several small scale-leaves,
the top ones form the terminal bud
small
scale-leaves
epicotyl
basal part
of cotyledon
hypocotyl
secondary roots
(one serving as a
water storage organ)
A
primary root
B
1
13 June 2011
2
3
B
4
RITA ZECCHINELLI
Asparagus densiflorus: abnormal seedlings
Normal seedling
Abnormal seedlings
1
1
2-3
4-5
6
7- 9
10
2
3
4
5
6
7
8
9 10
- 12/01 Secondary root serving as water storage organ weak or missing
- 11/04 Primary root missing
- 21/05 Epicotyl missing
- 12/01; 21/05 Secondary root and epicotyl missing
- 11/03; 11/04 Primary root retarded or missing
- 00/09 Seedling as a whole decayed as a result of primary infection
13 June 2011
RITA ZECCHINELLI
Asteraceae
Type E
Dycotiledons
Epigeal germination
Without epicotyl elongation
Dahlia pinnata
is the hypocotyl with two cotyledons
attached that turn green
13 June 2011
Substrate
Temperature
(°C)
TP; BP
2030; 20; 15
Counts
First
(d)
Final
(d)
4-7
21
Breaking
dormancy
Prechill
RITA ZECCHINELLI
Dahlia: development of the seedling during the test
•Start of germination: the primary root pierces the seed coat (1)
•The primary root elongates rapidly (2)
•The hypocotyl elongates and raises the cotyledons (3)
•The cotyledons become green and start photosynthesis (4).
During the test period, the seedling rarely develops secondary roots. The epicotyl
doesn’t develop and the terminal bud is hardly visible between the cotyledons.
1
13 June 2011
2
3
4
RITA ZECCHINELLI
Dahlia pinnata: abnormal seedlings
Normal seedling
1
3
4
1 - 11/04 Primary root missing
3 - 31/05 Cotyledons are discoloured
5 - 00/01 The seedling as a whole is deformed
13 June 2011
2
5
2 - 11/03 Primary root is retarded
4 - 31/05 Cotyledons are necrotic
RITA ZECCHINELLI
Type E
Dycotiledons
Epigeal germination
Without epicotyl elongation
Lamiaceae
Coleus blumei
Substrate
Temperature
(°C)
TP; BP
2030; 20
13 June 2011
Counts
First
(d)
Final
(d)
5-7
21
Breaking
dormancy
Light
RITA ZECCHINELLI
Coleus: development of the seedling during the test
•The hypocotyl elongates and raises the cotyledons (3)
During the test period, the seedling rarely develops secondary roots. The epicotyl
doesn’t develop and the terminal bud is hardly visible between the cotyledons.
1
13 June 2011
2
3
4
RITA ZECCHINELLI
Coleus blumei: abnormal seedlings
1
Normal seedling
2
3
Abnormal seedling
1 - 11/03 Primary root retarded
2 - 11/12 Primary root decayed as a result of primary infection
13 June 2011
RITA ZECCHINELLI
Primulaceae
Type E
Dycotiledons
Epigeal germination
Tuberous hypocotyl
Several seminal roots,
instead of a primary root
Cyclamen persicum
13 June 2011
RITA ZECCHINELLI
Substrate
Temperature
(°C)
TP; BP; S
20; 15
Counts
First
(d)
Final
(d)
14-21
35
(germination in the dark is suggested)
Breaking
dormancy
KNO3; soak
in water 24 h
Cyclamen: development of the seedling during the test
The seed of Cyclamen contains a small, straight embryo embedded in endosperm.
•Start of germination: the seed coat is pierced (1)
•The hypocotyl forms a tuber (2)
•Several seminal roots develop at the base of the hypocotyl (3)
•When the hypocotyl has completely emerged, it is followed by the petiole of one
cotyledon (4)
The blade of the cotyledon (A) seldom occurs during the test period.
The terminal bud takes place on the top of the tuber, at the base of the
cotyledon (B).
The first foliage leaf needs time to start the development.
A
B
1
13 June 2011
2
3
4
RITA ZECCHINELLI
NORMAL SEEDLINGS: examples
Unusual, but normal
13 June 2011
RITA ZECCHINELLI
ABNORMAL SEEDLINGS: examples
Normal seedling
00/01 – Seedling deformed
Normal seedling
11/08 Primary root shows negative
geotropism
Primary
root with negative
geotropism
11/02 Primary root stubby
21/02 Hypocotyl not
forming a tuber
Normal seedling
Normal seedling
13 June 2011
RITA ZECCHINELLI
ABNORMAL SEEDLINGS: examples
31/07 Cotyledon decayed as a result
of primary infection
Attention must be paid to sign of decay at the point where
the cotyledon petiole leaves the seed coat
13 June 2011
RITA ZECCHINELLI
Tropaeolaceae
Tropaeolum
peregrinum
Tropaeolum majus
Tropaeolum peltophorum
Tropaeolum spp.
13 June 2011
RITA ZECCHINELLI
Tropaeolum
spp.
Type G
Dycotiledons
Epigeal germination
Epicotyl elongation
The primary root may be
replaced by secondary roots
Tropaeolum majus
and turns green is the epicotyl with the primary leaves
Tropaeolum peltophorum
Tropaeolum peregrinum
13 June 2011
Temperature
(°C)
Substrate
TP;
BP; S
Counts
First
(d)
Final
(d)
4-7
21
Breaking
dormancy
20; 15
(and 2030
T. majus)
Prechill
RITA ZECCHINELLI
Tropaeolum majus: development of the seedling during the test
•Secondary roots soon develop (3)
•The hypocotyl is hardly discernible, the epicotyl elongates rapidly (4)
The buds in the axils of the cotyledons are usually dormant except if the terminal
bud is damaged.
1
13 June 2011
2
3
4
RITA ZECCHINELLI
Tropaeolum majus: abnormal seedlings
1
Normal seedling
4
2
5
1 - 00/01 Seedlings deformed
2 - 00/09 Seedling decayed as a result of primary infection
3 - 11/03 Primary root retarded
5 - 21/01 Epicotyl short and thick
6 - 21/03 Epicotyl deeply cracked
7 - 21/12 Epicotyl decayed as a result of primary infection
13 June 2011
3
6
7
RITA ZECCHINELLI
Fabaceae
Lupinus spp.
Lupinus nanus
Lupinus polyphyllus
Lupinus hartwegii
Lupinus hybrids
13 June 2011
RITA ZECCHINELLI
Lupinus hartwegii
Lupinus spp.
(flower species)
?
Type F
Dycotiledons
Epigeal germination
Epicotyl elongation
The primary root may be
replaced by secondary roots
and turns green is the hypocotyl with two cotyledons
And the epicotyl with the primary leaves
Temperature
(°C)
Substrate
Lupinus nanus
13 June 2011
Lupinus polyphyllus
TP;
BP; S
2030;
20
Counts
First
(d)
4-7
Final
(d)
21
Breaking
dormancy
L. hartwegii: pierce
seed; or file
fragment off testa at
cotyledon end;
prechill
RITA ZECCHINELLI
Lupinus polyphyllus: development of the seedling during the test
•Start of germination: the primary root breaks through the seed coat (1)
•The primary root elongates rapidly (2) and soon produces numerous secondary roots
•The hypocotyl elongates and the cotyledons are freed from the seed coat (3)
?
1
2
3
Substrate: paper
4
13 June 2011
RITA ZECCHINELLI
Lupinus polyphyllus vs Lupinus albus
Type F - Seedling Group A-2-1-2-2: secondary roots soon produced?
Lupinus polyphyllus (flower)
Lupinus albus (vegetable)
NO
any secondary roots produced
YES
(or only a few and very late)
secondary roots produced
Substrate: sand
13 June 2011
RITA ZECCHINELLI
Lupinus polyphyllus
Type F - Seedling Group A-2-1-2-2
Dycotiledons
Epigeal germination - Epicotyl elongation
The primary root may be replaced by secondary roots
→ YES
→ YES
→?
The seedling part that grows towards the light and turns green is the hypocotyl with two cotyledons
and the epicotyl with the primary leaves
Change to:
Type F - Seedling Group A-2-1-2-1 (new) ?
Change only the description of the
Development of the seedling during the test?
The other flower species of Lupinus
should be also investigated.
Looking for seeds!
13 June 2011
RITA ZECCHINELLI
Lupinus poliphyllus: abnormal seedlings
1
2
3
2 - 42/03 Primary leaf shredded or otherwise deformed
3 - 00/09 Seedling decayed as a result of primary infection
13 June 2011
RITA ZECCHINELLI
ISTA Flower Seed Committee
Flower species: there is some work to do
WORKING GROUPS
1) ISTA Flower Seed Testing Handbook
2) Validation study for Felicia heterophylla
(germination method/s)
3) Validation study for Alcea rosea
(germination method in sand)
4) Sample size for flower species (Tab. 2A
part 3)
5) Identification of Helianthus species by
seed
… Seedling evaluation in flower species of
Lupinus (NEW! To be still discussed)
Anyone willing to co-operate is welcome!
13 June 2011
RITA ZECCHINELLI
Photos of seeds and seedlings
Sylvie Ducournau
Zita Ripka
Digital Atlas of Economic Plants (http://www.plantatlas.eu/)
USDA Plant Database (http://plants.usda.gov/java/)
Digital collection of INRAN-ENSE Laboratorio Analisi Sementi, Italy
ISTA Handbook on Flower Seed Testing 1st Edition 2008
ISTA Handbook on Seedling Evaluation 3rd Edition 2003
ISTA Handbook on Pure Seed Definitions 3rd Edition 2010
Acknowledgements
Fabio Ferrari, Alessandra Arioli and colleagues
Sylvie Doucournau
Joël Léchappé
and
Luca Frigerio, the young artist of the drawing
‘Germination of a seed of violet’
And thank you for your attention!

Germination characteristics of flower species

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