Hi all

I never had a problem either with the 'plant pathology' definitions in papers. I even used them sucessfully in papers directed outside the strict 'plant pathology' community (for instance in papers in Journal of Evolutionary Biology or in Molecular Ecoiogy), provided that a precise definition was added. This is why I think the important point is to make it clear for the reader what concept is behind the term as you use it.

The same principle should apply for 'resistance', which is also highly polysemic and has been suppplemented over the years with a number of adjectives that basically add up to the confusion. The biggest problems in this case are 1) the multiple 'resistance+ adjective' combinations that designate exactly the same thing - synonymy - and 2) the use of one attribute to designate another characteristic (i.e., race-psecific resistance to designate 'non durable resistance'; which are not the same thing). It might be time for another review/meta-analysis/opinion paper to settle this once and for all - this would be a worthwhile addition to the existing literature!

Hi Jay Ram

There is a large debate regarding virulence and its definition. Indeed, plant pathologists use the term to designate infectiousness ( ie, the ability for one organism to infect another), whereas ecologists and evolutionary biologists call virulence the fitness reduction in the host caused by infection. This definition is rather close to what plant pathologists call aggressiveness.

The 'virulence= reduction of host fitness' is the one accepted by the larger community (there are far more ecologists and evolutionary biologists than plant pathologists!), and should probably be favored. However, for the plant pathologists, the whole literature corpus since Flor and Vanderplank is based on the alternative definition of virulence, and this makes it hard to change within that scientific disciplines.

The real important point, to me, is not the term being used, but to make sure that everyone is aware of the definition under which it is used. This is essential for controversial or polysemic terms like virulence.

I aklways used the two terms virilence and aggressivity  in exactly the way you addressed it, and my publications on aggressiveness of Leptosphaeria maculans on rape seed were never rejected. I like to stress, however, the point of view that Didier forwarded.

Hi all

I never had a problem either with the 'plant pathology' definitions in papers. I even used them sucessfully in papers directed outside the strict 'plant pathology' community (for instance in papers in Journal of Evolutionary Biology or in Molecular Ecoiogy), provided that a precise definition was added. This is why I think the important point is to make it clear for the reader what concept is behind the term as you use it.

The same principle should apply for 'resistance', which is also highly polysemic and has been suppplemented over the years with a number of adjectives that basically add up to the confusion. The biggest problems in this case are 1) the multiple 'resistance+ adjective' combinations that designate exactly the same thing - synonymy - and 2) the use of one attribute to designate another characteristic (i.e., race-psecific resistance to designate 'non durable resistance'; which are not the same thing). It might be time for another review/meta-analysis/opinion paper to settle this once and for all - this would be a worthwhile addition to the existing literature!

Thank you Didier, we seem to think very similar in These respects!

Thank you Didier for your clear response even while dealing with complex arguments. As for your idea on the possible paper to clarify such an issue, I will be honoured to contribute in this regard although I can't lead this task so far.

Cheers

JR

Hello all,

In my view, aggressiveness is the term that addresses the ability of a pathogen to grow and reproduce extensively on its host, regardless of the quantum of disease caused by it.