Institute for Crop Science and Plant Breeding
1
Bavarian State Research Center for Agriculture Institute for Crop Science and Plant Breeding 50% 60% 70% 80% 90% 100% combination I combination IIa combination I combination IIb location PU location AES Cross-pollination rates 90.0% n=107 79.6% n=104 94.3% n=88 90.7% n=43 vertical line = standard deviation Cross-pollination rates 90.0% n=107 79.6% n=104 94.3% n=88 90.7% n=43 vertical line = standard deviation 1 2 3 4 5 6 7 8 9 Vitality during germination and seedling cultivation (scoring marks, 1 = very weak to 9 = very strong) R² = 0.918 I 1 -lines 2012 I 2 -lines 2013 I 3 -lines 2014 I 4 -lines 2015/16 vertical line = standard deviation; n = 8 (highly) inbred parents open pollination Seeds produced by cross-pollination plant population in the field seed fraction F 1 > inbred lower vitality, reduced growth inbred descendant F 1 - Inbreed Michael Penzkofer, Stefan Seefelder, Heidi Heuberger What is the percentage of cross-pollinated seeds respectively inbred seeds in cross-pollinated populations? Is an inbreeding depression identifiable for inbred lines, that is, do inbred plants exhibit lower vitality? A B A B A B Contact: Bavarian State Research Center for Agriculture (LfL), Institute for Crop Science and Plant Breeding (IPZ3d), Vöttinger Str. 38, 85354 Freising, [email protected], www.LfL.bayern.de. • Selected valerian plants (elites) were propagated in-vitro (cloning). • Homozygously present DNA-based marker bands (AFLP) were examined in the first inbred generation (I 1 ). • Six elites were identified that differ in at least one homozygous band and were used in three pair combinations (I-IIa/IIb). • The mating clones were planted together in a poly-cross-system at two locations (PU-AES). • The seeds were taken separately from each plant and eleven descendants from each plant were analyzed. • In several steps, inbred lines with different levels of inbreeding (I 1 to I 4 ) were generated. • At each level of inbreeding a performance test was carried out in the field, evaluating the characteristics e.g. vitality during germination and seedling cultivation, crop coverage and vitality in field, as well as rootstock weight. B A References: BECKER, B., 2011: Pflanzenzüchtung. Eugen Ulmer, Stuttgart BERNÁTH, J., 1997: Cultivation of Valerian. In HOUGHTON, P. H. (ed.), Valerian The Genus Valeriana, harwood academic publishers, United Kingdom, 77-100 HEEGER, E. F., 1956: Handbuch des Arznei- und Gewürzpflanzenbaues. Deutscher Bauernverlag, Berlin. The observed high cross- pollination rates show the preference for cross-pollination, however autogamy is possible. (Similar reported in HEEGER, 1956 and BERNÁTH, 1997). Thus, the first and important condition for a hybrid variety from open pollination, without male-sterility system would be met. The detected inbreeding depression in inbred lines means that possibly formed inbred descendants will 'disappear' in field, saying that they will take a small fraction in the harvested material. Hybrid-breeding can only be exploited fully, if inbred lines are used (BECKER, 2011). Therefore, another inbred step in the F1 hybrid seed production will probably create plants with a much higher inbreeding depression. Basically the validity applies only for the tested clone combinations. Most likely, other clones or lines will behave similarly; however, in the end, the cross pollination rate of the developed hybrid variety must be determined.
Transcript of Institute for Crop Science and Plant Breeding
Bavarian State Research Center for Agriculture
Institute for Crop Science and Plant Breeding
50%
60%
70%
80%
90%
100%
combination
I
combination
IIa
combination
I
combination
IIb
location PU location AES
Cross-pollination rates
90.0%n=107
79.6%n=104
94.3%n=88
90.7%n=43
vertical line = standard deviation
Cross-pollination rates
90.0%n=107
79.6%n=104
94.3%n=88
90.7%n=43
vertical line = standard deviation
R² = 0,9176
1
2
3
4
5
6
7
8
9
1 2 3 4 5
Vitality during germination and seedling cultivation
(scoring marks, 1 = very weak to 9 = very strong)
R² = 0.918
I1-lines
2012
I2-lines
2013
I3-lines
2014
I4-lines
2015/16
vertical line = standard deviation; n = 8
(highly) inbred parents
open pollination
Seeds produced by cross-pollination
plant population in the field
seed fraction F1 > inbred
lower vitality, reduced growth
inbred descendant
F1-
In
breed
Michael Penzkofer, Stefan Seefelder, Heidi Heuberger
What is the percentage of cross-pollinated seeds respectively inbred seeds in cross-pollinated populations? Is an inbreeding depression identifiable for inbred lines, that is, do inbred plants exhibit lower vitality?
A
B
A
B
A B
Contact:
Bavarian State Research Center for Agriculture (LfL),
Institute for Crop Science and Plant Breeding
(IPZ3d), Vöttinger Str. 38, 85354 Freising,
[email protected], www.LfL.bayern.de.
• Selected va ler i an p l an ts (e l i tes) w ere propagated in -v i t ro (c loning ) .
• Homozy gous ly present DNA - based marker bands ( AFLP) w ere examined in the f i rst inbred generat ion ( I 1) .
• Si x e l i tes w ere ident i f ied that d i f fer in at least one h omozyg ous ba nd an d w ere used in three pa i r combinat ions ( I - I Ia / I Ib) .
• The mat ing c lones w ere p lant ed together in a poly - cross - system at two locat ions (PU - AES) .
• The seeds w ere taken separate ly f rom each p l ant an d e leven descendants f rom each p lant w ere analyzed .
• In seve ra l s teps , inbred l ines w ith d i f ferent leve ls of inbreeding ( I 1 t o I 4) w ere generated .
• A t each leve l of inbreeding a performance test w as carr ied out in the f ie ld , eva lu at ing the character ist ics e . g . v i ta l i ty dur ing germinat ion an d seedl ing cu lt ivat ion, crop coverage and v i ta l i ty in f ie ld , as w el l as rootstock w eight .
B
A
References: BECKER, B., 2011: Pflanzenzüchtung. Eugen Ulmer, Stuttgart BERNÁTH, J., 1997: Cultivation of Valerian. In HOUGHTON, P. H. (ed.), Valerian The Genus Valeriana, harwood academic publishers, United Kingdom, 77-100 HEEGER, E. F., 1956: Handbuch des Arznei- und Gewürzpflanzenbaues. Deutscher Bauernverlag, Berlin.
The observed high cross-pollination rates show the preference for cross-pollination, however autogamy is possible. (Similar reported in HEEGER, 1956 and BERNÁTH, 1997).
Thus, the first and important condition for a hybrid variety from open pollination, without male-sterility system would be met.
The detected inbreeding depression in inbred lines means that possibly formed inbred descendants will 'disappear' in field, saying that they will take a small fraction in the harvested material.
Hybrid-breeding can only be exploited fully, if inbred lines are used (BECKER, 2011). Therefore, another inbred step in the F1 hybrid seed production will probably create plants with a much higher inbreeding depression.
Basically the validity applies only for the tested clone combinations. Most likely, other clones or lines will behave similarly; however, in the end, the cross pollination rate of the developed hybrid variety must be determined.
