Publications by authors named "T D Meacham"
Potato virus Y (PVY) strains were originally defined by interactions with different resistance genes in standard potato cultivars. Five distinct strain groups are defined that cause local or systemic hypersensitive responses (HRs) in genetic background with a corresponding N gene: PVY(O), PVY(N), PVY(C), PVY(Z), and PVY(E). The nucleotide sequences of multiple isolates of PVY(O) and PVY(N) differ from each other by ≈8% along their genomes.
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- Potato virus Y (PVY) has been reported in Mexico, including variants affecting tobacco in the State of Mexico, but many areas are considered PVY-free and lack detailed strain distribution studies.
- In August 2009, a limited survey in Chihuahua collected over 900 potato samples, with only seven testing positive for PVY, primarily from specific potato cultivars like Fianna and Snowden.
- The isolated PVY-positive sample from the symptomless Fianna cultivar induced PVY symptoms in tobacco and was identified as a recombinant strain with characteristics from European PVY types, with further analysis using specific ELISA techniques confirming its classification.
A novel Potato virus Y (PVY) isolate, L26, recovered from a Frontier potato line was initially typed as a PVY(NTN) strain using multiplex RT-PCR and serological assays. However, L26 induced mosaic and mild vein clearing symptoms in tobacco rather than vein necrosis characteristic of the PVY (NTN) strain. The whole genome sequence was determined for L26 and two other PVY(NTN) isolates, HR1 and N4, from Idaho that did induce vein necrosis in tobacco.
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- Potato virus Y (PVY) significantly impacts potato production by reducing yields and quality, with management primarily relying on seed certification programs to mitigate initial virus levels.
- The ordinary strain of PVY was the most widespread in North America before 1990, characterized by clear foliar symptoms that facilitated visual inspections in seed potatoes.
- Recently, necrotic strains of PVY have emerged, causing mild symptoms that complicate detection and associated diseases like potato tuber necrotic ringspot disease (PTNRD), impacting tuber quality and contributing to the need for more sophisticated testing methods.
Potato virus Y (PVY) has become a serious problem for the seed potato industry, with increased incidence and rejection of seed lots submitted for certification. New PVY strains and strain variants have emerged in recent decades in Europe and North America, including the PVY strain that causes veinal necrosis in tobacco, and strain variants that represent one or three recombination events between the common strain (PVY) and PVY. Several reverse transcription-polymerase chain reaction (RT-PCR) assays have been described that characterize PVY isolates as to strain type, but they are limited in their ability to detect some combinations of mixed strain infections.
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