| dc.contributor.advisor | Becker, Heiko C. Prof. Dr. | |
| dc.contributor.author | Liu, Siyang | |
| dc.date.accessioned | 2016-01-06T09:43:52Z | |
| dc.date.available | 2016-01-06T09:43:52Z | |
| dc.date.issued | 2016-01-06 | |
| dc.identifier.uri | http://hdl.handle.net/11858/00-1735-0000-0028-8681-7 | |
| dc.identifier.uri | http://dx.doi.org/10.53846/goediss-5445 | |
| dc.language.iso | eng | de |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | |
| dc.subject.ddc | 630 | de |
| dc.title | Application of molecular markers in selected breeding material and plant genetic resources of Lolium perenne L. | de |
| dc.type | doctoralThesis | de |
| dc.contributor.referee | Backes, Gunter Prof. Dr. | |
| dc.date.examination | 2015-05-12 | |
| dc.description.abstracteng | Out-crossing perennial ryegrass (Lolium perenne L.) is the most
important forage grass species in temperate regions. It is also
proposed as a sustainable source of biomass for energy production.
However, the improvement of yield of perennial ryegrass in the past
years is not comparable to that of the other crops. The utilization of
hybrid breeding and the application of markers are therefore
anticipated to boost the breeding of perennial ryegrass. The objective
of the present study is to investigate the genetic diversity and the
presence of heterotic pools in selected L. perenne material by
applying molecular markers and the potential applications of molecular
markers in L. perenne hybrid breeding. For these purposes, 1384 DArT,
182 SNP and 48 SSR markers were applied to 297 perennial ryegrass
accessions. A bulk sampling strategy with 30 individuals per bulk
sample was employed and proofed to be efficient in distinguishing L.
perenne accessions. Within the 297 accessions, high polymorphism rate
was revealed for all the marker types: in DArTs, SNPs and SSRs, 1.99,
2.00 and 8.20 alleles per locus in average were obtained; The JD
(Jaccard distance) for DArT markers ranged from 0.00 to 0.73 with an
average of 0.45; the MRD (Modified Roger`s distance) for SNPs ranged
from 0.03 to 0.52 with an average of 0.34; the MRD for SSR markers
ranged from 0.26 to 0.76 with an average of 0.54. Genetic diversity
for dominant DArT and co-dominant SNP and SSR markers was found to be
0.26, 0.32 and 0.45, respectively. All the marker types are suitable
for the diversity study and DArT markers showed the highest
discriminative ability, consistency and reproducibility. The resulting
data was evaluated with different classification methods, but no clear
structure was found. Subsequently a subset of the plant material
containing nine CMS accessions and 76 pollinators was used to produce
the hybrids and conduct the field trial. Parental accessions as well
as their derivative hybrids were arranged in two sowing years (the
2010 sowings and the 2011 sowings) and FMY (fresh matter yield) and
DMY (dry matter yield) were recorded across five locations. For FMY,
the average MPH (Mid-parent heterosis) was found to be 13.88% and
3.24% for diploid hybrids in both sowings and 6.85% for tetraploid
hybrids; the average BPH (Better-parent heterosis) was 3.23% and
-1.10% for diploids in both sowings and 4.94% for tetraploid hybrids.
The pattern of DMY is similar to that of FMY. We further calculated
the correlation between MPH and genetic distances estimated from
molecular markers. In most cases, positive but weak correlations were
observed. Therefore the prediction of heterosis solely based on
genetic distances might not provide very accurate results. Our results
suggested a lack of heterotic patterns in the tested material. Further
investigations on the hybrid breeding should be aimed at the
identification of heterotic pools. The application of molecular
markers might serve as an efficient tool in assisting this process. | de |
| dc.contributor.coReferee | Isselstein, Johannes Prof. Dr. | |
| dc.subject.eng | lolium perenne | de |
| dc.subject.eng | SSR | de |
| dc.subject.eng | DArT | de |
| dc.subject.eng | SNP | de |
| dc.subject.eng | genetic diversity | de |
| dc.subject.eng | heterosis | de |
| dc.identifier.urn | urn:nbn:de:gbv:7-11858/00-1735-0000-0028-8681-7-5 | |
| dc.affiliation.institute | Fakultät für Agrarwissenschaften | de |
| dc.subject.gokfull | Land- und Forstwirtschaft (PPN621302791) | de |
| dc.identifier.ppn | 845367714 | |