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CHAPTER 6 Hybridization Breeding 杂交育种
Hybridization -Crossing v Sexual Crossing √ Asexual Crossing Distant Crossing -interspecific Crossing Intraspecific Crossing - inter-varietal Crossing In this chapter: Hybridization Breeding i.e. CROSS BREEDING
Hybridization – Crossing ✓ Sexual Crossing ✓ Asexual Crossing ▪ Distant Crossing - interspecific Crossing ▪ Intraspecific Crossing – inter-varietal Crossing In this chapter: Hybridization Breeding i.e. CROSS BREEDING
8 1 The Conception and Significance of Cross Breeding 杂交育种的概念和意义 What is Cross Breeding? P85 Crossing with different genotypes Trials for identification and selection New cultivar(s) Types of Cross Breeding Combination Breeding组合育种: Combination of diff. genes Transgression Breeding超亲育种 Accumulation of minor poly- g enes
1. What is Cross Breeding? P.85 Crossing with different genotypes Trials for identification and Selection New cultivar(s) Types of Cross Breeding: §1 The Conception and Significance of Cross Breeding 杂交育种的概念和意义 ✓ Combination Breeding 组合育种：Combination of diff. genes ✓ Transgression Breeding 超亲育种: Accumulation of minor polygenes
2. Significance of Cross Breeding The most widely used breeding method in present The most fruitful breeding method in present (p. 86) The combined use with other breeding methods
2. Significance of Cross Breeding The most widely used breeding method in present The most fruitful breeding method in present (p.86) The combined use with other breeding methods
8 2 Selection and Combination of Parents 亲本选择和选配 1. Selection of parents亲本选择 The Importance Pre-condition of successful breeding The principles p87 Large number of source materials Obvious objective characters Local popularized varieties Genetic characteristics of the objective characters
§2 Selection and Combination of Parents 亲本选择和选配 1. Selection of Parents 亲本选择 The Importance Pre-condition of successful breeding The Principles p.87 Large number of source materials Obvious objective characters Local popularized varieties Genetic characteristics of the objective characters
2. Combination of parents (1) Significance Key to successful breeding: (2)Principles 1)More advantages, less disadvantages; Complementary 2)Large genetic differences 3)High combining a bility GCA: Additive gene effects SCA: Heterosis effects(non-additive) Good cultivars are not always good parents 4)Salient objective characters in one or both parents, with a high inheritability 5)Select one locally popularized cultivar as one of the parents 3) Successful Selection and combination of parents in cross breeding Tab6-1,p.90
2. Combination of Parents (1) Significance Key to successful breeding: (2) Principles 1) More advantages, less disadvantages; Complementary 2) Large genetic differences 3) High Combining ability: GCA: Additive gene effects SCA: Heterosis effects (non-additive) Good cultivars are not always good parents 4) Salient objective characters in one or both parents, with a high inheritability 5) Select one locally popularized cultivar as one of the parents (3) Successful Selection and combination of parents in cross breeding Tab. 6-1, p. 90
s3 Modes of Cross and the Techniques 杂交方式和技术 1. Modes of Cross: Number of parents Modes of combination (1) Single Cross AXB or A/b(Cytoplasm from A) BXA or b/a(Cytoplasm from B) (2) Multiple cross 1) Three way cross (A×B)×CorA/B∥C( Cytoplasm ofA,C=1/2)
§3 Modes of Cross and the Techniques 杂交方式和技术 1. Modes of Cross: Number of parents Modes of combination (1) Single Cross A×B or A/B (Cytoplasm from A) B×A or B/A (Cytoplasm from B) (2) Multiple Cross 1）Three way cross (A×B)×C or A/B//C （Cytoplasm of A,C=1/2)
2) Double Cross (A×B)×(C×D)orA/B/C/D (A×B)×(A×C)orA/B∥AC(A=12) 3) Tetra cross A/B/C/3/D(D=1/2) 4)Convergent Cross A/B/CD/3/E/F∥G/H
2）Double Cross (A×B)×(C×D) or A/B//C/D (A×B)×(A×C) or A/B//A/C (A=1/2) 3）Tetra Cross A/B//C/3/D (D=1/2) 4) Convergent Cross A/B//C/D /3/ E/F//G/H
( 3)Backcross AB//A AB/B (4) Multiple parental cross A/B+C+D+E)
(3) Backcross A/B//A A/B//B (4) Multiple Parental Cross A/(B+C+D+E)
2. Techniques of Crossing (1)Regulation/timing of flowering stages (2)Emasculation 3)Pollination (4)Post management
2. Techniques of Crossing (1) Regulation/timing of flowering stages (2) Emasculation (3) Pollination (4) Post management