园艺植物生物技术第五章选编.ppt

Plant chromosomal engineering植物染色体工程;Plant chromosomal engineering;Part 1 Production of Haploids;①monohaploids单元单倍体 即具有来自二倍体中染色体数目一半的单倍体，如玉米，大麦等； ②polyhaploids多倍单倍体 即具有来自多倍体中染色体数目一半的单倍体，如马铃薯，小麦等。 ;3. Production methods ;3．1 ANDROGENIC METHODS 雄核发育方法;;外植体选择;;3.1.2 Microspore Culture小孢子培养;花药培养、花粉培养的异同点： 培养目的相同，均获得小孢子植株 花药培养属于器官培养；而花粉培养属于细胞培养 花粉培养没有药壁组织干扰；可计数小孢子产胚率；可观察雄核发育的全过程；单倍体产量高，但技术更复杂;3.1.3 The various factors governing the success of androgenesis 影响雄核发育的因素;3.1.4 Process of androgenesis雄核发育过程; 胚状体发育途径;芸苔属小孢子培养;愈伤组织发育途径;愈伤组织转接种到再生培养基;3．2 GYNOGENIC HAPLOIDS雌核发育单倍体;Factors affecting gynogenesis影响单雌生殖的因素;4. The ploidy level and chromosome doubling倍性水平和染色体加倍;5. Diploidization二倍化;6. Significance and uses of haploids单倍体的意义和应用;;7. Problems;1. High level of management and expertise is required to operate the tissue culture production of haploids. 2, Diploids and tetraploids often regenerate at the same rate as the haploids. 3. Selective cell division must take place in the haploid microspores and not in other unwanted diploid tissues. This selective cell division is often impossible. 4. Callus formation whether it has arisen spontaneously or has been induced by regulators is usually detrimental.5. The relatively high incidence of albinism in some types of anther and pollen culture. 6. The lack of selection of traits during the derivation of haploid material. 7. There is little chance of isolating a haploid from a mixture of haploids and higher ploidy levels since latter ones are easily outgrown. 8. The doubling of a haploid does not always result in the production of a homozygote.;Part 2 Production of polyploid;;1.1 polyploid： 体细胞中含有3个或3个以上染色体组的生物体 同源多倍体（autopolyploid）：指多倍体的几个染色体组来源于同一物种。 如：AAA--同源三倍体；AAAA--同源???倍体 异源多倍体（allopolyploid）：指来自不同种属的染色体组成的多倍体（染色体组来源不同）。　　　　AABB--异源四倍体（又叫双二倍体），类似于二倍体的远缘复合物。;a.巨大性： 一般表现在叶大；茎粗；花大，色浓；果实、种子、细胞、气孔、花粉都大 如三倍体、四倍体葡萄粒大；四倍体萝卜主根粗大;b.育性低： 一般同源多倍体结实率低 原因：同源多倍体由于在减数分裂时，染色体间配对不正常，易出现多价体，致使多数配