Fertility Restoration in Garlic

EU project “Garlic and Health” - Work Package 2

Rina Kamenetsky and Haim D. Rabinowitch

Idit London, Marina Baizerman, Ada Harazy and Amit Shiftan

Garlic (Allium sativum) is a completely

sterile plant, propagated only

vegetatively

Increase of genetic variation occurs only

via random or induced mutations,

new cultivars are bred by clonal selection

Allium longicuspis from Central Asia, a

member of the garlic taxon, is probably

the most primitive one.

Background information

Sterility was assumed to result from (Etoh & Simon, 2002)

• Nutritional competition between floral and vegetative buds in the

developing inflorescence (Koul and Gohil, 1970)

• Degeneration of the tapetum (Novak, 1972)

• Degenerative-like disease (Konvicka, 1973)

• Chromosomal deletions (Etoh, 1985)

• Hormonal imbalance and competition for resources between

the simultaneously forming bulb, growing cloves and

developing inflorescence (Pooler & Simon, 1994)

Garlic clones are classified according to their ability to bolt:

1. Complete bolting: long stalk with many flowers and topsets

2. Incomplete bolting: thin short stalk with a few large topsets

3. Nonbolting: producing only cloves inside incomplete scape

(Takagi, 1990)

Missions to Central Asia in 2000 and 2001, resulted in a collection of 241 accessions, including wild populations and land-races.

Incomplete-bolting accession

Bolting accession

Bolting garlic

J. Am. Soc. Hortic. Sci. (2004) Developmental Physiology

Environmental Control of Garlic Growth and Florogenesis

Rina Kamenetsky, Idit London Shafir, Hanita Zemah, Amalia Barzilay and H. D. Rabinowitch

1 - 8 9 10 11 12 13Weeks of experiment

20/120C

23/150C

20/12C20/12C

SD

LD

LD

SD 23/15C23/15C

20/120C 23/15CLDLD

SD

SD

SD

SD

SD

20/12C20/12C20/12C20/12C

SD

SD

SD

SD

23/15C23/15C23/15C23/15C

SD

SD

SD20/120C

20/120C

Fig. 1. Phytotron thermo- and photo-period treatments in 2001-2002 experiments. Propagation bulbs were subjected to 60 days of constant storage temperature at 40C prior to planting. Short days (SD) = 10 hrs insolation; Long days (LD) = 10 hrs sunlight followed by 10 hrs of incandescent light.

1

3

2

5

6789

10111213

4

Treatmentnumber

Plants under continuous SP did not

bolt and produced numerous axillary

leaves

Following stratification, seeds were sown in November

Garlic nursery: A general view Individual garlic seedling, accession No. 500

March, 2002

TreatmentLeaf number prior to floral

initiation

Maximum scape length

Sprouting cloves

Dormant cloves

SD - LD1054.310

SD 13010

LD757.410

SD - 1 w LD - SD1031.510

SD - 2 w LD - SD1354.79

SD - 3 w LD - SD1260.59

SD - 4 w LD - SD1356.09

Growth temperatures 20/12 – 23/150C

incomplete-bolters

5

10

15

20

Coun

t Axis

9 10 11 12 13 14 15 16 17 18

100.0%

99.5%

97.5%

90.0%

75.0%

50.0%

25.0%

10.0%

2.5%

0.5%

0.0%

maximum

quartile

median

quartile

minimum

17.670

17.670

17.582

15.670

14.830

11.585

10.330

10.000

9.365

9.330

9.330

Quantiles

Mean

Std Dev

Std Err Mean

upper 95% Mean

lower 95% Mean

N

12.62214

2.42410

0.37405

13.37754

11.86674

42.00000

Moments

mean leaf no.

Distributions

bolters

5

10

15

Coun

t Axis

8.5 9 9.5 10 10.5 11 11.5 12 12.5

100.0%

99.5%

97.5%

90.0%

75.0%

50.0%

25.0%

10.0%

2.5%

0.5%

0.0%

maximum

quartile

median

quartile

minimum

12.000

12.000

12.000

11.653

11.000

10.330

9.830

9.347

8.670

8.670

8.670

Quantiles

Mean

Std Dev

Std Err Mean

upper 95% Mean

lower 95% Mean

N

10.41571

0.80401

0.09610

10.60743

10.22400

70.00000

Moments

mean leaf no.

Distributions

semi bolters

mean leaf no.

No.

of

accessio

ns

Mean leaf number

bolters

5

10

15

20

Coun

t Axis

9 10 11 12 13 14 15 16 17 18

100.0%

99.5%

97.5%

90.0%

75.0%

50.0%

25.0%

10.0%

2.5%

0.5%

0.0%

maximum

quartile

median

quartile

minimum

17.670

17.670

17.582

15.670

14.830

11.585

10.330

10.000

9.365

9.330

9.330

Quantiles

Mean

Std Dev

Std Err Mean

upper 95% Mean

lower 95% Mean

N

12.62214

2.42410

0.37405

13.37754

11.86674

42.00000

Moments

mean leaf no.

Distributions

bolters

5

10

15

Coun

t Axis

8.5 9 9.5 10 10.5 11 11.5 12 12.5

100.0%

99.5%

97.5%

90.0%

75.0%

50.0%

25.0%

10.0%

2.5%

0.5%

0.0%

maximum

quartile

median

quartile

minimum

12.000

12.000

12.000

11.653

11.000

10.330

9.830

9.347

8.670

8.670

8.670

Quantiles

Mean

Std Dev

Std Err Mean

upper 95% Mean

lower 95% Mean

N

10.41571

0.80401

0.09610

10.60743

10.22400

70.00000

Moments

mean leaf no.

Distributions

semi bolters

mean leaf no.

T F

Frequency distribution of scape length (42 accessions)

0

2

4

6

8

10

12

14

0 1 2 3 4 5 6 7

scape length (cm)

freq

uenc

y

40-50 60-7050-60 90-10080-9070-80

T

F

Leaf Scape Flower/topset Pollen

number length, cm index germination, %

Early (15/5 - 5/6) 10.6±0.17 61.2±1.75 T 0

Mid (5/6 - 25/6) 13.4±0.46 80.7±2.7 F 94.74

Late (25/6 - 5/7) 15.7±1.02 78.4±6.8 F 100

Date of spathe breaking

Physiological parameters of bolting garlic (42 accessions)

Newly-formed bulbs from seeds varied by…

1 cm1 cm

skin colour

1 cm1 cm

bulbing ability 1 cm1 cm

bulb size and clove formation

Publications:

• Kamenetsky, Rina and H. D. Rabinowitch (2001).Floral development in bolting garlic. Sexual Plant Reproduction 4, 235-241

• Kamenetsky, Rina, Idit London Shafir, Hanita Zemah, Amalia Barzilay and H. D. Rabinowitch (2004). Environmental control of garlic growth and florogenesis. J. Am. Soc. Hort. Sci. (in press)

Ada Harazy

Amit Shiftan

Amalia BarzilayMarina Baizerman

Yizhak Forer

Hanita Zemah

Idit London Shafir

SPECIAL THANKS