The Mechanism of 2n Pollen Formatiom in Populus × euramericana and P. × popularis
Speaker Jin-feng Zhang (Jennifer) zjf@bjfu.edu.cn Beijing Forestry University P.R.China
OUTLINE
1 Introduction 2 Materials and Methods 3 Results and Analysis 4 Discussion
1 Introduction
1.1 Polyploid breeding is an important part in poplar breeding
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Triploid white poplar trees Triploid and aneuploid hybrids in Populus trichocarpa × P. deltoides
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Triploidy were found in the cultivar poplar clones in section Aigeiros
1 Introduction
1.2 Mechanisms of 2n gamete formation in plant
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Premeiotic doubling Omission of the first or second meiotic division Abnormal spindle Abnormal cytokinesis Nuclear fusion
FDR ( first division restitution ) : Contains non-sister chromatids SDR ( second division restitution): Contains two sister chromatids
1 Introduction
1.3 The objective of this study
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Poplar can produce 2n gamete naturally or by artificial induction Elucidation of the cytological mechanisms of 2n gamete formation has been seldom in poplar. To detect and elucidate the mechanisms of 2n pollen formation in diploid poplar Results from this research may offer a more effective method for polyploid breeding in poplar in section Aigeiros.
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2 Materials and Methods
2.1 Plant materials
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Populus × euramericana Four male : EA1, EA2, EA3 and EA4 One female: A
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P. × popularis The offspring of (P. simonii × (P.nigra var pyramidalis + Salix matsudana mixed pollen) ) One Male: P
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The crosses
A × EA1, A ×EA2, A × EA3, A × EA4, A×P
2 Materials and Methods
2.2 Microsporogenesis observation 2.3 Flow cytometry analyses 2.4. Chromosome counting 2.5. SSR analysis
3. Results and Analysis
3.1 Cytological determination on 2n pollen formation
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Table 1 The expected and observed rate of 2n pollen grains
Sporads Code of