烟草NtHMA4基因突变体鉴定及低镉特性研究

Identification and Low Cadmium Characteristics Research of NtHMA4 Mutant in Tobacco

该研究从中国烟草主栽品种‘云烟87’的EMS突变体库中,通过TILLING技术筛选,获得NtHMA4的EMS突变体hma4-4h12。对突变体进行测序表明,该突变体核苷酸突变方式为C152T,氨基酸突变方式为T51I。利用100μmol/L氯化镉对突变体进行镉胁迫试验表明,hma4-4h12与对照‘云烟87’相比,叶片中镉、锌、铜、砷、铅、镍含量分别降低55.48%、21.11%、20.96%、27.50%、16.23%和19.28%,铁、锰和铬含量与对照没有显著差异。hma4-4h12突变体大田农艺性状观察表明,其株高、节距、茎围等与对照相比显著变小,推测hma4-4h12中含有影响这些性状的突变位点。该研究获得的低镉突变体hma4-4h12可以作为培育低镉烟草品种的材料,但是育种中利用该突变体,后续还需要通过回交去除不利突变的影响。

EMS mutant of NtHMA4,hma4-4h12,was screened from mutant library of main tobacco cultivar‘Yunyan 87’in China by TILLING technology in this study.Sequencing of the mutants showed that the mutation of nucleotides was C152T in the hma4-4h12,and the mutation of amino acid in the hma4-4h12 was T51I.The content of cadmium,zinc,copper,arsenic,lead and nickel in hma4-4h12 leaf were decreased by 55.48%,21.11%,20.96%,27.50%,16.23%,and 19.28%respectively compared with those of control after 100μmol/L CdCl 2 treatment.hma4-4h12 was planted in the field and its agronomic traits were observed.Plant height,stem circumference and intermodal length of hma4-4h12 were decreased significantly compared with those of control.It was speculated that hma4-4h12 contained mutant loci affecting these traits.The low cadmium mutant,hma4-4h12,obtained from this study can be used as a material for cultivating low cadmium tobacco varieties.However,the use of this mutant in breeding requires further backcrossing to remove the negative mutation.