Propidium monoazide combined with qPCR to differentiate live and dead conidia of Neofabraea actinidiae

  • Lucia Ramos Plant & Food Research
  • I.P. Shamini Pushparajah Plant & Food Research
  • M. Shahjahan Kabir Plant & Food Research
  • Bethan E. Parry Plant & Food Research
  • Kerry R. Everett Plant & Food Research

Abstract

Neofabraea actinidiae can occasionally cause post-harvest rot in kiwifruit. Quantitative polymerase chain reaction (qPCR) analysis represents a feasible and accurate option for identifying and quantifying this rot but is limited because qPCR results do not differentiate live and dead conidia. Propidium monoazide (PMA) is a photoreactive dye that penetrates into the damaged cell-wall membranes of dead conidia binding to the DNA and thus suppressing its amplification by qPCR. A commercial kit containing PMA was trialled for differentiating between live and dead N. actinidiae conidia. The most suitable conditions were 1 μM PMA with 10 min light emitting diode (LED) exposure, and could clearly distinguish high concentrations of live from similar concentrations of dead conidia when tested separately and as a mixture. Low concentrations of live N. actinidiae conidia could be distinguished from dead ones when tested separately, but not as a mixture. Additional work is needed to optimise the effectiveness of the PMA binding and apply this concept in the orchard.

Published
2018-07-30
How to Cite
Ramos, L., Pushparajah, I. S., Kabir, M. S., Parry, B., & Everett, K. (2018). Propidium monoazide combined with qPCR to differentiate live and dead conidia of Neofabraea actinidiae. New Zealand Plant Protection, 71, 348. https://doi.org/10.30843/nzpp.2018.71.218
Section
Vol 71 Poster Abstracts 2018