| Abstract | 第6页 |
| Abbreviations | 第7-9页 |
| 1 Introduction | 第9-11页 |
| 2 Literature review | 第11-21页 |
| 2.1 Types of chromosome manipulation in citrus | 第11-12页 |
| 2.2 The importance of polyploidy manipulating for citrus genetic improvement | 第12-14页 |
| 2.3 Mitotic-chromosome doubling in plant tissues | 第14-18页 |
| 2.3.1 Mitosis division: as a target of antimitotic doubling agents | 第14-15页 |
| 2.3.2 The antimitotic agents induce the chromosome manipulation | 第15-17页 |
| 2.3.3 Application methods of antimitotic agents for chromosome duplication | 第17-18页 |
| 2.4 Identification methods of the chromosome-duplicated plants | 第18-21页 |
| 2.4.1 The stomatal analysis | 第18-19页 |
| 2.4.2 Chromosome counting | 第19页 |
| 2.4.3 Morphological and developmental characteristics | 第19-20页 |
| 2.4.4 Flow cytometry (FCM) analysis | 第20-21页 |
| 3 The objective | 第21-22页 |
| 4 Materials and methods | 第22-29页 |
| 4.1 Plant materials and growth conditions | 第22页 |
| 4.2 Preparation of plant materials | 第22-23页 |
| 4.3 Colchicine treatments | 第23-24页 |
| 4.4 Ploidy level assessment | 第24-25页 |
| 4.5 Morphological observation | 第25页 |
| 4.6 Stomatal analysis | 第25-26页 |
| 4.7 Anatomy analysis | 第26-27页 |
| 4.8 Photosynthesis measurement | 第27页 |
| 4.9 Statistical analysis | 第27-29页 |
| 5 Results | 第29-40页 |
| 5.1 Effects of in vitro colchicine application on the treated tissues | 第29-30页 |
| 5.2 Effects of in vivo colchicine treatment on the treated tissues | 第30-31页 |
| 5.3 Ploidy examination of regenerated shoots | 第31-32页 |
| 5.4 Stomatal comparison between the regenerated shoots | 第32-34页 |
| 5.5 Histological comparison between leaf blades of the regenerated shoots | 第34-35页 |
| 5.6 Morphological comparison between 2x and 4x plants | 第35-36页 |
| 5.7 Gas exchange comparison between diploids and tetraploids | 第36-38页 |
| 5.8 Chlorophyll a fluorescence comparison between 2x and 4x | 第38-40页 |
| 6 Discussion | 第40-45页 |
| 6.1 The polyploidy of P.trifoliata increases the photosynthesis efficiency | 第40-43页 |
| 6.2 The in vivo colchicine application in citrus efficiently produce tetraploids | 第43-45页 |
| 7 References | 第45-51页 |
| ACKNOWLEDGEMENTS | 第51-52页 |
