新引进果蔗品种宿根矮化病菌检测

Detection of Leifsonia xyli subsp. xyli,Causal Bacterium of Sugarcane Ratoon Stunting Disease for Introduced Cultivars of Fruit Cane

采用PCR和巢式PCR技术对6个新引进果蔗品种黔蔗08-1497,黔糖5号,云南红皮,广东黄皮,黔蔗08-688,黔糖3号和广东主栽果蔗品种黑皮果蔗(Badila)进行宿根矮化病菌检测,并对其中广东黄皮、云南红皮、黔糖3号及黑皮果蔗(Badila)的巢式PCR第二轮扩增产物(编号依次为Lxx-Gd-gz1、Lxx-Gd-gz2、Lxx-Gd-gz3及Lxx-Gd-gz4)进行核苷酸序列测定及分析。结果表明,PCR检测,仅黔蔗08-688甘蔗宿根矮化病菌检出率为20%(1/5),其余6个果蔗品种的宿根矮化病菌检出率均为0%;巢式PCR检测,黔蔗08-1497及黔糖5号宿根矮化病菌检出率为0%,广东黄皮检出率为75%;云南红皮、黔蔗08-688、黔糖3号及黑皮果蔗(Badila)检出率均为100%。Lxx-Gd-gz1、Lxx-Gd-gz2、Lxx-Gd-gz3及Lxx-Gd-gz4基因组相应区段核苷酸序列同源率为100%,均与巴西、澳大利亚、美国路易斯安娜州、中国云南、中国福建及广东湛江株系核苷酸序列同源率均为99%。表明该病菌遗传稳定性极高,变异极小。

PCR and nested-PCR were used to detect Leifsonia xyli subsp. xyli（Lxx）,the causal bacterium of sugarcane stunting disease（RSD） were collected from seven different cultivars of fruit cane,including Qianzhe 08-1497,Qiantang No. 5,Yunnan hongpi,Guangdong huangpi,Qianzhe 08-688,Qiantang No. 3 and Badila,and the nucleotide sequence determination and analysis in fruit cane cultivars of Guangdong huangpi,Yunnan hongpi,Qiantang No. 3 and Badila（isolate number followed Lxx-Gd-gz1,Lxx-Gd-gz2,Lxx-Gd-gz3 and LxxGd-gz4） amplified products of nested-PCR in the second round were made. The results showed that RSD bacteria detection rate was 20 %（1 /5） only in Qianzhe 08-688,and Lxx detection rate was 0 % in the remaining six fruit cane cultivars by using PCR detection; However,Lxx detection rate was 0 % only in Qianzhe 08-1497 and Qiantang No. 5,Guangdong huangpi detection rate was 75 %; Yunnan hongpi,Qianzhe 08-688,Qiantang No. 3 and Badila detection rate was 100 % by nested-PCR detection. The intergenic transcribed spacer（ITS） region of 16s-23 s r DNA of Lxx-Gd-gz1,Lxx-Gd-gz2,Lxx-Gd-gz3 and Lxx-Gd-gz4 isolates shared almost 100 % nucleotide identity each other and shared almost 99 % nucleotide identity with Brazil,Australia,USA（Luisanna）,China（Yunnan Province,Fujian Province and Zhanjiang City,Guangdong Province） isolates. It was that the genetic stability of Lxx was extremely high,and the variation was minimal.