Melgarejo Tomas A, Kon Tatsuya, Gilbertson Robert L
Phytopathology. 2015 Jan;105(1):141-53. doi: 10.1094/PHYTO-05-14-0135-R.
In the Dominican Republic (DO), jatropha plants with yellow mosaic symptoms are commonly observed in and around fields of various crop plants. Complete nucleotide sequences of DNA-A and DNA-B components of four bipartite begomovirus isolates associated with symptomatic jatropha plants collected from three geographical locations in the DO were determined. Sequence comparisons revealed highest identities (91 to 92%) with the DNA-A component of an isolate of Jatropha mosaic virus (JMV) from Jamaica, indicating that the bipartite begomovirus isolates from the DO are strains of JMV. When introduced into jatropha seedlings by particle bombardment, the cloned components of the JMV strains from the DO induced stunting and yellow mosaic, indistinguishable from symptoms observed in the field, thereby fulfilling Koch's postulates for the disease. The JMV strains also induced disease symptoms in Nicotiana benthamiana, tobacco, and several cultivars of common bean from the Andean gene pool, including one locally grown in the DO. Asymmetry in the infectivity and symptomatology of pseudorecombinants provided further support for the strain designation of the JMV isolates from the DO. Thus, JMV in the DO is a complex of genetically distinct strains that have undergone local evolution and have the potential to cause disease in crop plants.
在多米尼加共和国(DO),在各种农作物田地及其周边常见到具有黄色花叶症状的麻风树植株。测定了从DO三个地理位置采集的与有症状麻风树植株相关的四种双分体菜豆金色花叶病毒分离物的DNA - A和DNA - B组分的完整核苷酸序列。序列比较显示,与来自牙买加的麻风树花叶病毒(JMV)分离物的DNA - A组分具有最高的同一性(91%至92%),这表明来自DO的双分体菜豆金色花叶病毒分离物是JMV的株系。当通过粒子轰击将来自DO的JMV株系的克隆组分导入麻风树幼苗时,诱导了发育迟缓及黄色花叶症状,与在田间观察到的症状无法区分,从而满足了该病害的柯赫氏法则。这些JMV株系还在本氏烟草、烟草以及来自安第斯基因库的几个普通菜豆品种(包括DO当地种植的一个品种)中诱导了病害症状。假重组体在感染性和症状学方面的不对称性为来自DO的JMV分离物的株系命名提供了进一步支持。因此,DO的JMV是一组遗传上不同的株系的复合体,这些株系经历了局部进化,并且有可能在农作物中引发病害。