农业生物技术学报-2004

《农业生物技术学报-2004》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、农业生物技术学报JournalofAgriculturalBiotechnology2004,12(3):237~246(专家论坛(柑橘体细胞杂种及其核质遗传研究进展*刘继红徐小勇邓秀新"华中农业大学作物遗传改良国家重点实验室’国家农作物分子育种中心’武汉430070%摘要：原生质体融合能够克服柑橘多胚$雌和/或雄性败育等生殖障碍’为柑橘"Citrusspp.%品种改良提供新的途径&柑橘原生质体融合主要采用)叶肉原生质体+胚性愈伤组织原生质体*和)胚性愈伤组织原生质体+胚性愈伤组织原生质体*两种模式’融合方式主要有对称和非对称融合&通过原生质体融合已获得200余个组

2、合的体细胞杂种’杂种倍性多样’绝大多数为异源四倍体’其次为叶肉亲本型二倍体’此外还获得了一些其它倍性的杂种植株&体细胞杂种在柑橘品种改良上的应用主要是砧木改良和用作倍性杂交培育无核三倍体的亲本&柑橘体细胞杂种的鉴定方法有细胞学$形态学和遗传标记&柑橘体细胞杂种核质遗传研究表明’四倍体体细胞杂种核主要为双亲之和’二倍体体细胞杂种核来自叶肉亲本’叶绿体DNA表现出单向或单亲分离’在个别组合中有双亲叶绿体DNA共存现象+线粒体DNA主要来自悬浮系亲本’仅在少数组合中观察到重组或丢失现象&关键词：柑橘+体细胞杂种+核+线粒体DNA+叶绿体DNA+品种改良Advanceson

3、CitrusSomaticHybridsandInheritanceofTheirNuclearandCytoplasmicComponents*LIUJi-HongXUXiao-YongDENGXiu-Xin(NationalKeyLaboratoryofCropGeneticImprovement,NationalCenterofCropMolecularBreeding,HuazhongAgriculturalUniversity,Wuhan430070,China)Protoplastfusioncancircumventreproductivebarrie

4、rsfacingcitrus,suchaspolyembryonyandfemaleand/ormalesterility,andpaveswayforcitruscultivarimprovement.Twokindsoffusionpatternswereemployedforcitrus,leaf-derivedprotoplasts+embryogeniccallusprotoplastsandembryogeniccallusprotoplasts+embryogeniccallusprotoplasts.Morethan200casesofsomatic

5、hybridshavebeenobtainedviasymmetricandasymmetricfusions,mostofwhichareallotetraploids,followedbyleaf-parent-typediploidsandplantsofotherploidy.Thesomatichybridsholdgreatpotentialforcitrusrootstockimprovementandcanbeusedasstaminateparentsforinterploidycrossesaimingtoproduceseedlesstripl

6、oids.Thesomatichybridscanbeidentifiedbycytology,morphologyandgeneticmarkers.Nuclearandcytoplasmicgenomescharacterizationofthesomatichybridsdemonstratedthatthetetraploidsomatichybridspossessedadditivenuclearcomponentsfrombothfusionparents,whereasonlyleafparents'nuclearpatternsweredetect

7、edinthediploidsomatichybridswithmorphologysimilartotheleafparent.UnilateraloruniparentalsegregationofcpDNAwasobservedinmostofthesomatichybridswiththeexceptionofcpDNAco-existenceinfewcases.AsfarasmtDNAismainlyconcernedtheorganellederivedfromtheembryogenicparentswhichpresentedinthesoma