ACCase Trp-1999-Leu突变对菵草种子萌发的影响

Effects of Trp-1999-Leu Mutation in ACCase on Seed Germination of Beckmannia syzigachne

为了确定菵草(Beckmannia syzigachne)乙酰辅酶A羧化酶(acetyl-coenzyme A carboxylase,ACCase)Trp-1999-Leu突变对种子萌发的影响,采用衍生酶切扩增序列多态性法(derived cleaved amplified polymorphism sequences,dCAPS)从JS-26种群中分离出基因背景一致的1999位突变纯合子(1999Trp/Trp,RR)和野生型(1999Leu/Leu,SS),并在室内测定其种子萌发的动态差异,及在pH、水分、盐等胁迫下的萌发差异。结果表明,Trp-1999-Leu突变能够提高菵草种子的萌发率,使菵草种子在偏酸性或偏碱性条件下的萌发率降低;但能显著提高菵草种子萌发对水分和盐胁迫的耐受力,水势为-0.4 MPa时,RR萌发率比SS高23个百分点,NaCl浓度为80 mmol/L时,RR的萌发率为SS的4.4倍。

In order to ascertain the effects of Trp-1999-Leu mutation in ACCase on the seed germination of Beckmannia syzigachne,the mutant homozygotes(RR)and wild type(SS)on the 1999 site with same genetic background were purified from JS-26 population using the derived cleaved amplified polymorphism sequences(dCAPS)method.The germination differences of RR and SS were studied in controlled conditions.The results indicated that Trp-1999-Leu mutation could improve the germination rate but reduced in acid or alkaline environment.It significantly increased the germination rate under drought or salty stress.The germination rate of RR was 23 percentage points higher than that of SS when the water potential was-0.4 MPa,while that was 4.4 times when the concentration of NaCl reached to 80 mmol/L.