甘蓝型油菜抗茎倒材料的筛选与候选基因挖掘

Selection of Germplasm Resources and Digging for Candidate Genes of Stem Lodging Resistance in Brassica napus L.

该研究采用茎秆抗折力指标评价了200份甘蓝型油菜种质资源抗茎倒伏能力,据此筛选出极端抗茎倒材料和不抗茎倒材料各1份,随后测定了2份材料成熟期茎秆的理化组分含量,并对2份极端抗茎倒差异材料蕾苔期、盛花期茎秆进行转录组测序分析,为甘蓝型油菜抗茎倒伏的遗传改良奠定基础。结果表明:(1)200份甘蓝型油菜种质资源的茎秆抗折力和茎粗均为正态分布,均属于数量遗传性状,并依据茎秆抗折力和农艺性状筛选出生育期相近,株型相似,茎秆粗度差异不显著,但茎秆抗折力差异显著的极端不抗茎倒材料GY172和抗茎倒材料GY199。(2)GY199的韧皮部比GY172更加致密,而GY172成熟期茎秆中的半纤维素、木质素、中性洗涤纤维及总可溶性糖含量均显著高于GY199,而其纤维素含量极显著低于GY199,即成熟期茎秆纤维素含量与这2个材料的茎秆抗折力呈正相关。(3)蕾苔期、盛花期茎秆转录组测序发现,碳代谢、碳固定、磷酸戊糖途径、氨基酸的生物合成、糖酵解/糖异生等途径的14个基因(BnaA10G0056100ZS、BnaC08G0455100ZS、BnaA08G0262400ZS、BnaC08G0239700ZS、BnaA07G0362300ZS、BnaC02G0081300ZS、BnaC04G0273000ZS等)以及纤维素合成相关的9个基因(BnaA05G0152200ZS、BnaA01G0411100ZS、BnaA03G0018900ZS、BnaA03G0037800ZS等)在抗茎倒材料GY199中显著上调表达,这些基因可能参与调控了茎秆强度性状,可作为油菜抗茎倒候选基因。

In this study,we used the stem bending resistance index to evaluate the resistance to stem lodging of 200 Brassica napus germplasm resources,based on which,one extreme stem lodging resistance material and one non stem lodging resistance material were screened,and then we measured the content of physical and chemical components in the stems of the two materials at maturity,and carried out the transcriptome sequencing analysis of the stems of the two extreme stem lodging resistance materials at the bud stage and full flowering stage,for laying the foundation for genetic improvement of stem lodging resistance in Brassica napus.The results showed that:(1)the stem breaking resistance and stem diameter of 200 Brassica napus germplasm resources were all normal distribution,which belonged to quantitative genetic traits.The extremely non resistant stem fall material GY172 and anti stem fall material GY199,which had similar birth dates,plant types and stem diameter,but significant differences in stem breaking resistance,were screened based on stem breaking resistance and agronomic traits.(2)The phloem of GY199 was denser than that of GY172,while the content of hemicellulose,lignin,neutral detergent fiber and total soluble sugar in the mature stem of GY172 was significantly higher than that of GY199,while the content of cellulose in the mature stem was extremely significantly lower than that of GY199.The content of cellulose in the mature stem was positively correlated with the stem bending resistance of the two materials.(3)Sequencing of stem transcriptome at bud moss stage and full bloom stage revealed that carbon metabolism,carbon fixation,pentose phosphate pathway,amino acid biosynthesis 14 genes(BnaA10G0056100ZS,BnaC08G0455100ZS,BnaA08G0262400ZS,BnaC08G0239700ZS,BnaA07G0362300ZS,BnaC02G0081300ZS,BnaC04G0273000ZS,etc.)were resistant to stem.The expression was significantly up-regulated in metamaterial GY199,these genes may be involved in regulating stem strength traits and serve as candidate genes for stem lodging resistance in rapeseed.