B. Schneider et al., Comparison and characterization of tomato big bud- and sweet potato littleleaf-group phytoplasmas, J PHYTOPATH, 147(1), 1999, pp. 31-40
Citations number
32
Categorie Soggetti
Plant Sciences
Journal title
JOURNAL OF PHYTOPATHOLOGY-PHYTOPATHOLOGISCHE ZEITSCHRIFT
EcoRI or HindIII-restricted DNA from phytoplasmas associated with tomato bi
g bud (TBB) and sweet potato little leaf (SPLL-V4) was cloned into pBluescr
ipt and the recombinant plasmids were screened by reciprocal DNA hybridizat
ion with TBB- and SPLL-V4 DNA. Most of the recombinant plasmids hybridized
to DNA of both phytoplasmas. Southern hybridization analysis of EcoRI- or H
indIII-restricted TBB- and SPLL-V4 DNA with two TBB probes (pTBB32 and pTBB
87) gave identical restriction patterns. Southern hybridizations of HindIII
- or EcoRI digested DNA from 10 phytoplasma-positive field samples revealed
a different restriction fragment pattern in two phytoplasmas from sweet po
tato. Three TBB probes which did not hybridize to SPLL-V4 were selected for
Southern blot analysis of samples. The pTBB42 and pTBB78 hybridized to nin
e of the 10 TBB-symptomatic held samples producing identical patterns. pTBB
88 contained extrachromosomal DNA and hybridized with two phytoplasmas from
diseased sweet potato and perennial phlox;. The SPLL-V4-specific probe pH
21 hybridized to five field samples generating different restriction patter
ns. About 80 held samples were subjected to the polymerase chain reaction u
sing primers deduced from pH21, pTBB32 and pTBB88, These phytoplasmas had b
een previously characterized and grouped by their 16S/23S spacer region res
triction fragment pattern but this classification was in most cases differe
nt to the results obtained with these primers.