TY - JOUR
T1 - Stylosanthes is a host for several phytoplasmas, one of which shows unique 16S-23S intergenic spacer region heterogeneity
AU - De La Rue, Stephanie Jane
AU - Padovan, Anna
AU - Gibb, Karen
PY - 2001/10
Y1 - 2001/10
N2 - Stylosanthes sp. exhibiting characteristic symptoms such as little leaf, witches' broom and ̄oral abnormalities were collected from north Queensland and the Northern Territory, Australia. Previous studies have shown that sweet potato little leaf V4 (SPLL-V4), tomato big bud (TBB), stylosanthes little leaf (StLL) and pigeon pea little leaf (PLL) phytoplasmas are associated with this disease. The detection of an additional phytoplasma type, vigna little leaf (ViLL) is reported herein. The range and severity of symptoms expressed by affected plants is highly variable and is not associated with a particular phytoplasma type. Similarly, host plants infected with a complex of two phytoplasmas did not have unique or more severe symptoms. Of the phytoplasmas associated with stylosanthes little leaf disease, StLL is unique because it lacks the tRNAIle gene which is normally situated in the 16S-23S rRNA intergenic spacer region. This phytoplasma was shown to have a second operon containing the expected tRNAIle gene in all StLL samples examined. Sequence analysis suggests that the two 16S rRNA genes amplified by polymerase chain reaction from StLL samples originate from the same phytoplasma. This the first report of a phytopl- asma having ribosomal operons both with and without an intergenic tRNAIle gene.
AB - Stylosanthes sp. exhibiting characteristic symptoms such as little leaf, witches' broom and ̄oral abnormalities were collected from north Queensland and the Northern Territory, Australia. Previous studies have shown that sweet potato little leaf V4 (SPLL-V4), tomato big bud (TBB), stylosanthes little leaf (StLL) and pigeon pea little leaf (PLL) phytoplasmas are associated with this disease. The detection of an additional phytoplasma type, vigna little leaf (ViLL) is reported herein. The range and severity of symptoms expressed by affected plants is highly variable and is not associated with a particular phytoplasma type. Similarly, host plants infected with a complex of two phytoplasmas did not have unique or more severe symptoms. Of the phytoplasmas associated with stylosanthes little leaf disease, StLL is unique because it lacks the tRNAIle gene which is normally situated in the 16S-23S rRNA intergenic spacer region. This phytoplasma was shown to have a second operon containing the expected tRNAIle gene in all StLL samples examined. Sequence analysis suggests that the two 16S rRNA genes amplified by polymerase chain reaction from StLL samples originate from the same phytoplasma. This the first report of a phytopl- asma having ribosomal operons both with and without an intergenic tRNAIle gene.
KW - polymerase chain reaction
KW - phytoplasma
KW - Stylosanthes
KW - tRNA
UR - http://www.scopus.com/inward/record.url?scp=0034764699&partnerID=8YFLogxK
U2 - 10.1046/j.1439-0434.2001.00683.x
DO - 10.1046/j.1439-0434.2001.00683.x
M3 - Article
VL - 149
SP - 613
EP - 619
JO - Journal of Phytopathology
JF - Journal of Phytopathology
SN - 0931-1785
IS - 10
ER -