torquill: A sweet potato flower (gardening)
You really do see everything in this job. Tomatoes are my crop of choice: they give clear signals of illness or health, their requirements are pretty simple and easy, and the results are really very rewarding. So I've seen a lot of things happen with tomatoes, and I understand how they function in most situations.

I got sent some pictures today by the help desk, which has been stumped for a week by a diagnosis problem. I did have a reply, but only after my eyebrows hit my hairline. I'd never seen edema on tomatoes before -- technically, just about any dicot can get it, but while I've encountered it on a host of plants (citrus is particularly prone) this is a first for me. Edema presents differently on every plant, but if a tomato were to get it, I can believe that's what it would look like.

It wasn't just the lumpy stems that looked like they were ready to sprout adventitious roots across 75% of their surfaces (but no roots were growing). It was the combination of cold rain (thus wet conditions) alternating with bright hot sun *and* a fertilizing regime of 19-19-19 every two weeks. Bingo!

On the plus side, they'll be fine, as long as the gardener lays off for a while. It's left me shaking my head, though... I guess now I know what it takes to spur widespread edema lesions on tomatoes.
torquill: Coveralls with the patches "Henry's Garage" and "Forensics" (henry)
So the Chronicle ran an article this week about the Berkeley sick plant clinic. Oh boy, thought I; we had been hoping for a few more people, but having an article on the front page of Wednesday's Datebook section is just asking for it. Meanwhile, our lead pathologist is on a trip to China at the moment, so I'm all we've got for pathology. I braced for impact as best I could.

It started heavy and stayed that way. I gave up on a tally almost immediately, but Alice was running logistics and managed to keep one between new arrivals; it shows about 44 people came in. The heaviest month I can recall in recent years was 15, and it usually runs closer to 9. I shunted as many people as I could to the entomologists, bless Emma and Nick both; Emma also took a bunch of basic pathology questions alongside the bug queries. It was Nick who jumpstarted my response on the last customer's problem, because my brain was starting to drip out my ears. Fortunately, control measures for leaf spot diseases have been drilled into me for so many years now I can recite them in my sleep, so all it took was his mention that it was probably "that leaf spot disease that shows up on ornamental pears all the time" for me to snap into focus and start talking about Entomosporium and sanitation measures. Though I admit, I had never seen it on fruiting quince before.

I think I did well in my "trial by fire", as Emma calls it, though it felt like a three-hour practical exam. Looking over my responses, they all seem reasonable. It was a day of bad news (oak root fungus and viruses) and good news (edema and cause for hope in a maple with Verticillium). We may have saved a fifty-year-old cherry tree, and taught a lot more people about codling moth. Not a bad morning at all, and worth the eyestrain and the sense that my brain had been pulped. Next time maybe there will be enough of a break for me to go to the bathroom and eat breakfast. :)

For now: don't wanna think for a while.
torquill: Art-deco cougar face (dork)
You know you're a plant pathologist when you get excited over a really good picture of grey wall disorder in tomatoes.* Not to mention the chance to diagnose it, after endless rounds of Alternaria blight and blossom end rot... even if the solution is to throw up the hands and say "we really don't know why it happens". At least it's unusual, not fatal, and not contagious.




* But there are so few good pictures of it on the web!
torquill: A sweet potato flower (gardening)
This is really only of interest to gardeners, but if you are one and you've been told that some of your favorite plants have been dying from the oak root fungus (Armillaria mellea), the foremost question in your mind is "how do I deal with it?" Resistant plants are about the only answer.

Unfortunately, the UC guidelines for susceptibility are about 20 years out of date, and the updated list Dr. Bob Raabe created after several years of research has never been published. Since people need this information, I converted the PDF to HTML and posted it here: Plants Resistant to the Oak Root Fungus. You will find easy-to-read tables of resistant and susceptible plants there, and a link to the PDF for download.

It's currently hosted on my personal server; it may move to a spot on the UC Botanical Gardens site or one of the Master Gardener websites if we figure out where it would be best. I didn't want to delay getting it out there any longer, however. If it moves, I'll provide a redirect so you can still find it at the above link.
torquill: Art-deco cougar face (dork)
I just upped my plant bio geek credentials.

I don't expect anyone here to buy these, but perhaps I can peddle them to the other plant path folk... The joke is just a little too odd for anyone else, sadly. :)
torquill: Art-deco cougar face (mad science)
I now know so much about the mechanism behind making transgenic (GMO) food crops that I can no longer engage in public discussion about it. Sigh.

Let it be noted, however, that after all this education, my only objection to crops modified to resist pests and diseases is the public reaction... there is no scientific basis I can determine for blocking such transgenic-resistance plants. Ditto for making plants used in pharm-acology. I'm not so sanguine about Roundup-Ready crops, which seem largely like a bid by Monsanto to lock in their Roundup market without a huge impact in effectiveness... but that's the minority of modifications looking for approval. Most of them are either used solely in lab research (for genomics and such), modified to make a foreign substance (such as a medicine), or given a gene conferring resistance to a disease or insect. And in almost all cases, the benefits outweigh the drawbacks (many of which exist even with normal crops).

That doesn't mean they should be forced down people's throats, so to speak. Public resistance is a very good reason to hold back on introducing such things to the food supply, and I think a lot of the pro-GMO folks have been ignoring that. I just wish they'd wake up and start working with the public on education and assuaging public fears, rather than screaming that the objectors are simply stupid Luddites. Until the public can have its fears rationally addressed, there's going to be backlash, and quite rightly so.
torquill: Art-deco cougar face (bean)
When I showed up at the plant clinic this morning, I was sure that it would be a long morning -- I was greeted with the news that neither of the pathologists was coming.

Now, we did have Dr. Nick, and Emma, our erstwhile entomologists... but the pathologists are the main diagnosticians, and the backbone of the plant clinic. Without them, we're kind of fumbling in the dark. Ann was on vacation, and Dr. Raabe wasn't feeling well enough yet to come, but the show must go on...

We all chipped in: the Master Gardner assistants (of which I'm one) fielded incoming supplicants as usual, and then the people were simply seen by whoever was free at the time. We had a group of Liz (an assistant who's been around for a long while but who has no formal training), Dr. Nick, and occasionally me who would brainstorm on what was laid before us, and Alice tried to assist Emma as she took on any case that came her way. I got tapped for a couple of cases and did my best, which was fortunately quite adequate for the problems that came in.

We came out of it quite grateful that the problems we saw were so straightforward: yellowing citrus, signs of lack of water, lots of scale insects, mealybugs, codling moth... lots of insects, so the entomologists were confident, and very few mysteries. Everyone seemed to come away feeling like they had an answer, whether it was positive news or not. I even saw Dr. Nick taking a stab at diagnostic questions, and he usually defers all the disease issues to the pathologists on sight.

The clinic volunteers came together and did much better than I had expected; I've been rather dreading the situation of "what if neither Bob nor Ann could make it?" Now I know. Having Dr. Nick there was reassuring, but I think we could have managed without him if we had to. The lack of a lab was frustrating -- we couldn't tell people "oh, we'll culture this and find out for sure" -- but in most cases a culture isn't really necessary. We told people what to look for in their own yards, and what to do with what they saw.

We had the weirdest thing come in -- it looked like a series of tiny champagne flutes without stems, stuck upright in the ground, maybe a centimeter tall. They had what seemed to be seedlike organs inside, but the outside looked like either a mushroom or a cell from a wasp's nest. We couldn't figure out whether they were fungal, insect-created, or a primitive sort of plant (though with the seedlike constructions I'd almost bank on the latter, with things like liverworts). The unopened buds looked like fungal fruiting bodies, but there were no hyphae at the base. We didn't manage to identify it, and several people took bits of it home.

Someone came in with a sprig of what looked like a citrus rootstock, if the 1.5" thorn was any indication, with a small green fruit on it. He said that all it produced were these small, fuzzy orbs that were more pith than fruit, though they did eventually turn orange. I took a look at the fruit (it really was fuzzy) and cracked, "It must be a fuzzy navel!" I then had to assure the man that no, really, it wasn't. (At least I thought it was funny.) We agreed that it would be excellent to use if he wanted to practice his grafting skills, as he thought he might.

I do hope Bob is feeling well enough to come soon, but he's very old and getting rapidly more fragile. I was worried that the clinic might fall apart without him... today was a good sign that it may survive even then.
torquill: Art-deco cougar face (Default)
I usually take information from the Pesticide Action Network with a grain of salt; even though I've been chemically injured and deal poorly with many of the pesticides they campaign against, their tone has always struck me as overly hysterical. That said, they sometimes do a good job of aggregating other news reports and summarizing studies, and this one seems like a good read.

Carbaryl: One Poison for Another in Urban Creeks

Read more... )
torquill: Art-deco cougar face (Default)
This caught my eye, mainly because it has to do with plant pathology. It is, however, also a tale of the same sort of corruption that pervades the current White House. Which makes sense, given who Katherine Harris is.

Pressure was put on Florida officials to test "Celestial Water" as a cure for citrus canker

I haven't researched citrus canker specifically, but I remember hearing that it's been a real scourge in Florida over the last four years or so. It's a bacterial disease, and the combination of wet weather (which helps it spread from tree to tree) and hurricanes (which injured the trees, making wounds where disease could enter) has made a serious impact on the citrus orchards. The only treatment for most cankers is to cut off the affected parts, which in many cases in Florida has meant taking out trees entirely. Everyone's looking for some other way, but I don't know of any.

When Katherine Harris, who knows absolutely zip about plant disease, hooks up with a New York Rabbi and a cardiologist to suggest a cure, it makes me angry that scientists have to comply with ignorant superstitious beliefs just because of who she is. Other quacks are brushed off with a quiet "do the research and let us know". Yet this Kabbalist dreck gets tested by the state, because a U.S. Representative is breathing down people's necks.

Gah. I get irritated by politicians messing with climate change data, but I guess when they mess with my profession, it gets personal.

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Torquill

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