摘要
远缘杂交及多倍化是物种形成和种质创新的基础,将陆地棉与野生瑟伯氏棉进行远缘杂交及染色体加倍获得可育杂种。旨在将瑟伯氏棉的有益农艺性状转移到陆地棉中,拓宽陆地棉的遗传基础。以陆地棉为母本,瑟伯氏作父本进行远缘杂交合成杂种F_(1),并进行染色体加倍,获得异源六倍体,对F_(1)及异源六倍体进行形态学、细胞学、生理生化及SSR分子标记鉴定。形态学鉴定结果表明,异源六倍体植株整体与杂种三倍体相似,介于双亲之间,异源六倍体的雄蕊多于亲本及F_(1),有淡红色的花斑,与亲本及F_(1)都不同。细胞学鉴定表明,随着倍性的增加,气孔密度呈下降趋势,而气孔长度、叶绿体数和花粉粒直径均呈上升趋势;杂种三倍体(F_(1))和异源六倍体的减数分裂行为表明,二者的减数分裂均有正常和异常行为,三倍体中的多分体较多,而六倍体正常四分体明显增多。三倍体的多分体中,正常四分体占比为24.33%;六倍体的多分体中,正常四分体占比为82.17%,表明六倍体的育性在恢复。生理生化结果表明,酶的活性随不同世代倍性的增长而升高。SSR鉴定结果表明,三倍体杂种和异源六倍体既扩增出了父母本的条带,同时也扩增出了新的特异性条带,表明远缘杂交过程中产生了染色体重组现象。通过远缘杂交成功合成陆瑟杂种,通过染色体加倍成功获得了可育的异源六倍体。
Distant hybridization and polyploidization are fundamental processes for the development of new species and germplasm innovation.In this study,we obtained fertile offsprings by interspecific distant hybridization and chromosome doubling between Gossypium hirsutum and Gossypium thurberi.The objective is to penetrate beneficial agronomic traits of G.thurberi into G.hirsutum and expand the genetic diversity of G.hirsutum.In this study,we obtained hybrid F_(1)by synthesizing the female parent G.hirsutum with the male parent G.thurberi,and had allohexaploid cotton by chromosome doubling.And then we examined the morphology,cytology,physiology,biochemistry and SSR molecular markers of the F_(1)and allohexaploid.The results of morphological identification showed that the allohexaploid plant was similar to the heterotriploid,with mid-parents'characters.The allohexaploid had more stamens than the parent and F_(1)had,with reddish spots,which were different from the parents and F_(1).Cytological identification showed that stomatal density was in a decreasing trend with the increase of ploidy;while stomatal length,chloroplast number and pollen grain diameter all showed an increasing trend.The meiotic behavior of heterotriploids and allohexaploids revealed that both normal and abnormal tendencies,with more polyploids in triploids and significantly more normal tetrads in hexaploids.In triploids,the percentage of normal tetrads was 24.33%,while the percentage of normal tetrads was 82.17%in the polyploid hexaploids,indicating the recovery of hexaploid fertility.Physiological and biochemical results showed that the activities of enzymes increased with the increase of ploidy in different generations.The SSR molecular marker identification results revealed that distant hybridization led to chromosomal recombination in triploid hybrids and heterohexaploids,resulting in the amplification of both parental bands and new specific bands.The comprehensive results show that hybrids are successfully synthesized by distant hybridization and fertile heterohexaploids are successfully obtained by chromosome doubling,which provides valuable materials for cotton germplasm innovation and further genetic research.
作者
候林慧
郑赟
荣二花
吴玉香
HOU Lin-hui;ZHENG Yun;RONG Er-hua;WU Yu-xiang(College of Agriculture,Shanxi Agricultural University,Taigu 030801)
出处
《生物技术通报》
CAS
CSCD
北大核心
2023年第12期128-135,共8页
Biotechnology Bulletin
基金
山西省基础研究计划(自由探索类)(20210302124154)
国家自然科学基金项目(31171599)。
关键词
瑟伯氏棉
远缘杂交
异源六倍体
形态性状鉴定
生理生化鉴定
细胞学鉴定
SSR
G.thurberi
distant hybridization
allohexaploid
character identification
physiological and biochemical index
cytology identification
SSR
