Many devastating oomycete pathogens utilise effector proteins to enter plant cells and promote virulence. Effector proteins can manipulate plant processes to the advantage of the pathogen- they can alter the physiology, development and immune system of the host cell.

One such effector is known as an RxLR effector. Evidence suggests that RxLR effectors are required for translocation into the plant cell.

Preliminary evidence indicates that one oomycete species, Phytophthora pluvialis, could potentially have over 100 RxLR effector proteins.

Phytophthora pluvialis is the causative agent of Red Needle Cast, a destructive disease of radiata pine and Douglas-fir. To understand the disease-causing mechanism of P. pluvialis, a radiata pine yeast two-hybrid (Y2H) cDNA library has been constructed to identify putative host protein targets of effector proteins.

Our understanding of the infection process of P. pluvialis at a molecular level is rudimentary compared to other Phytophthora species. Knowledge on P. pluvialis effectors and their targets will define, for the first time, the plant immune receptors/R genes in Pine.

Understanding the key mechanisms of infection is vital as it gives insight into development of preventative measure such as targeted breeding strategies, forestry strategies, or development of chemical treatments.