Change of Goals
Well I know I've not been keeping up on this blog very regularly but I'm going to post an update. I have been thinking long and hard about my career goals and I have come to the decision that I do not need a Phd to do what I want to do after graduate school. After a very stressful year I have decided that I don't want to get a Phd but I will write up my thesis for a masters and I hope to defend it this coming spring.
Long time no post
I've just built some irrigation in a hoop house at the farm. Here are two photos of the trial I have running currently to test the set up. I'm hoping the central plant (inoculated with warm season phytophthora spp) will spread their infection to the surrounding healthy Rhodies.
Southern Red spider mites
More mites! Since southern red spidermites were found on Pieris plants in the chamber I had to toss all those plants and order more. The chamber has since been completely cleaned out and decontaminated.
mite outbreak
We found spider mites which feed on cultures in some phytophthora plates so we had to throw out a lot of cultures and decontaminate the incubators. This has set things back a little bit in the lab. I have instead been getting going with some data analysis of my field experiments which have been running for a year now. It's nice to see the seasonal differences in the species of phytophthora which do best at different temperatures. I now have more ideas about what to move forward with and I can repeat a second year of data to gain more confidence in my results.
Koch's Postulates
Activation of isolates was successful with almost all isolates so I am now able to move on to carry out Kochs postulates with them. The aim of Koch's postulates is to confirm a diagnosis that a particular suspected organism is causing the observed disease. The steps were first described by Robert Koch in 1882 and later added to by Erwin F Smith in 1905. The steps are as follows:
1. determine the suspected pathogen is consistently associated with the disease
2. isolate the suspected pathogen from the diseased plant and grow it in pure culture on artificial media and describe it.
3. Inoculate the isolated organism onto a healthy plant of the same species to see if it causes the same disease symptoms.
4. Re-culture the pathogen and determine that it is the same as the original isolate.
Steps one and two have already been completed so I am now going to work on steps 3 and 4.
1. determine the suspected pathogen is consistently associated with the disease
2. isolate the suspected pathogen from the diseased plant and grow it in pure culture on artificial media and describe it.
3. Inoculate the isolated organism onto a healthy plant of the same species to see if it causes the same disease symptoms.
4. Re-culture the pathogen and determine that it is the same as the original isolate.
Steps one and two have already been completed so I am now going to work on steps 3 and 4.
Isolate activation
I am hoping to 'activate' some isolates by inoculating them into rhododendrons and then re-isolating them from the plant after infection has occurred in an attempt to remind the isolates how to be virulent. Some times we have isolates that have been maintained for so long in culture that they start to behave strangely or they stop sporulating for example. This is a technique to re-activate them before using them in experiments.
Soil inoculation relative success
I have been trying to inoculate rhododendron roots with Phytophthora spp for a while and Kim and I have tried several methods that are reported in the literature. I set my latest trial up in the mist chamber to maximise the water availability and finally I seem to have symptoms all be it in only one rep out of three and on only one species out of 7 but never the less I have symptoms yay. See the wilting plant on the right compared with happy plant on the left.
Detached leaf experiment
I ran another repeat of my detached leaf inoculation where I dip inoculate leaves in zoospores suspension and incubate them without wounding for 2 weeks. I spent 8 hours on Labor Day doing this and it looks as though it hasn't worked. This is the fourth time I have set this experiment up and the other 3 times I got good data, although the trends don't exactly match what I expected at least the leaves got infected. This time I was meticulous so I can't figure out why only 9 leaves out of 150 developed lesions. Gah! At least this shows the expected trend but there are so many misses I can't really use this as quantitative data. Perhaps I can just note the observations. So disheartening.
In case you haven't already noticed I have joined twitter and I'm having my tweets posted to the gadget in the right column of this blog so if you want to get an insight into what I am doing on a daily basis this will contain little snippets. You can follow me on twitter - @claret84
New photos of farm inoculation
are available to view through Picasa as a slide show on my photography blog.
Plants inoculated in the mist chamber
P. citricola
P. citrophthora
P. citrophthora
P. syringae
P. cinnamomi
P. nicotianae
googly eyes
I posted a little video at the bottom of this page, just for fun. It is a sketch from Saturday Night Live. The site that hosts the video streams an advert before the video begins. It's pretty funny I think.
beautiful drip spread lesions
Here are some new photos from today in the mist chamber, the Phytophthoras are doing nicely in there where it is all wet.
Current Activities
I'm helping to compile data from a study looking at a potential new species of Phytophthora, and conducting kochs postulates on several isolates in collaboration with another lab. I'm also pulling together the data from my poster to put into a paper written by a post doc in our lab to try to get that published too. I'm running a mist chamber inoculation concurrently with my field work to compare findings at 2 different temperatures under very moist conditions. I will also be repeating a detache leaf inoculation using P. ramorum as I obtained rather strange results last time.
that's all for now
that's all for now
APS meeting
Here I am at the American Phytopathological Society Meeting in Portland OR earlier this week. I presented this poster on the pathogenic fitness of the clonal lineages of Phytophthora ramorum.
Disease spread
The first photo shows P. syringae spreading aerially, probably by rain splash during winter. The second photo shows P. nicotianae spreading within the plant during late spring/early summer.
research in the news
Here is an article from February of last year on the Salem news website, talking about the importance of research on Phytophthora spp. and other pathogens for the nursery industry in Oregon which recently exceeded $1bn in sales value. Several people I work with are mentioned and my project on the epidemiology of Phytophthora spp on Rhododendron is mentioned.
Field experiment
Finally I am having some success at inoculating my field experiment. Here is a graph showing my initial data. There are significant differences between species and between cultivars and as expected P. syringae (7) is the most aggressive pathogen so far. 
This photo shows a Rhododendron inoculated with Phytophthora syringae as part of my field experiment. You can see how the infection has spread aerially by rain splash to near by leaves and has dripped down on to the two leaves below the inoculated leaf.
This photo shows a Rhododendron inoculated with Phytophthora syringae as part of my field experiment. You can see how the infection has spread aerially by rain splash to near by leaves and has dripped down on to the two leaves below the inoculated leaf.
trip to the state capitol
On Friday I went to the capitol building in Salem to testify in favour of house bill 2508 for the abolition of fees for graduate students with a tuition waiver. I went along with other members of the Coalition of Graduate Employees (CGE) the union for the grads on OSU's campus, and the GTFF which is the equivalent at the University of Oregon. The GTFF and CGE are part of the larger union, the American Federation of Teachers (AFT).
the proposed HB 2508 would stop the universities in Oregon from charging fees on top of tuition to graduate students when we have funding which provides a tuition waiver. The current situation sees 17% of my net pay go back to the university each year, last year this amounted to $2840.
Here is a photo of members of CGE and the GTFF in front of the capitol after testifying for over an hour to a concerned committee.
It was a great experience and it seemed that they committee really took on board our message although in these economic times of severe budget cuts it seems unlikely that any dramatic changes will occur in the near future but hopefully this will begin to open up conversations about how we can improve the situation for graduate students in Oregon.
The CGE has also posted remarks about Friday's trip on their blog and you can download an audio recording of the proceedings from Friday's hearing here. The hearing for HB 2508 begins 16min 29sec into the recording and I testify at 38min 15sec and it closes at 1hr 36min 26sec after 12 testimonies in favour of the bill and 1 agains the bill (someone sent to represent the university).
the proposed HB 2508 would stop the universities in Oregon from charging fees on top of tuition to graduate students when we have funding which provides a tuition waiver. The current situation sees 17% of my net pay go back to the university each year, last year this amounted to $2840.
Here is a photo of members of CGE and the GTFF in front of the capitol after testifying for over an hour to a concerned committee.
It was a great experience and it seemed that they committee really took on board our message although in these economic times of severe budget cuts it seems unlikely that any dramatic changes will occur in the near future but hopefully this will begin to open up conversations about how we can improve the situation for graduate students in Oregon.The CGE has also posted remarks about Friday's trip on their blog and you can download an audio recording of the proceedings from Friday's hearing here. The hearing for HB 2508 begins 16min 29sec into the recording and I testify at 38min 15sec and it closes at 1hr 36min 26sec after 12 testimonies in favour of the bill and 1 agains the bill (someone sent to represent the university).
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