Durable resistance to Phytophthora cactorum in strawberry and apple

The oomycete pathogen Phytophthora cactorum causes disease in over 250 plant species, including causing economic losses in cultivated strawberry (Fragaria x ananassa) and apple (Malus x domestica). P. cactorum is the causative agent of crown rot and leather rot diseases in strawberry, as well as crown rot, collar rot and root rot diseases in apple. Extensive work has been carried out at NIAB EMR identifying resistance quantitative trait loci (QTL) in response to isolates of P. cactorum from strawberry (Nellist et al. 2018), as well as sequencing 19 isolates of P. cactorum from both strawberry and apple. Isolates of P. cactorum from apple are unable to cause disease in strawberry, and so further work is required to explore non-host (broad-spectrum and durable) resistance to these isolates. In addition to this, apple rootstock germplasm is to be screened for resistance/susceptibility to isolates of P. cactorum from apple and QTL mapping will be performed. Pathogenicity screens with isolates of P. cactorum from strawberry are to be performed and non-host resistance in apple to these isolates are to be explored.

References
  1. Nellist CF, Vickerstaff RJ, Sobczyk MK, Marina-Montes C, Brain P, Wilson FM, Simpson DW, Whitehouse AB, Harrison RJ. (2018) Quantitative Trait Loci Controlling Phytophthora cactorum Resistance in the Cultivated Octoploid Strawberry (Fragaria x ananassa). https://www.biorxiv.org/content/early/2018/01/18/249573
  2. Lee H-A, Lee H-Y, Seo E, Lee J, Kim S-B, Oh S, Choi E, Choi E, Lee SE and Choi D. (2017) Current understandings of plant nonhost resistance. Molecular Plant-Microbe Interactions 30:1, 5-15. https://apsjournals.apsnet.org/doi/abs/10.1094/MPMI-10-16-0213-CR