Tuesday, December 22, 2009

Monday, November 9, 2009

Corn Ear Mold Update

I just wanted to provide an update on corn ear molds. We are getting a lot of questions here in the clinic regarding Fusarium and the potential for mycotoxins. We are seeing Fusarium on corn, but whether or not it will lead to mycotoxins is debatable. The information we are gathering says it depends on the moisture content of the corn going into storage. Amy Ziems, Diagnostician from the University of Nebraska, has posted the following to our GPDN listserv: "In Nebraska we are experiencing a tremendous amount of grain mold. Currently the harvest is approximately 3 weeks behind due to all the wet weather we have been experiencing the past 2 months also majority of the corn in the field is testing between 18-40% moisture. In the lab we have been seeing a few of the common ear molds such as Diplodia and Fusarium ear rots, however we are seeing a lot of corn with green/black sporulation on the ears and cobs. The green/black sporulation is a combination of several different saprophytic fungi including Alternaria, Pithyomces and Ulocladium. Attached are a couple of photos of the "moldy" corn. Our current recommendation here is dry the corn below 15% within 24 hrs after harvest prior to storage. We are feeling that these fungi have the potential to cause some major damage during storage if the moisture levels are not dropped significantly. We are also receiving a lot of questions regarding mycotoxin testing with the fusarium ear molds being detected." Amy has also provided a list of companies that do mycotoxin testing. If you are interested in having your corn tested, please feel free to contact me at the diagnostic clinic and I will be happy to provide you with the list or I can direct your sample to the nearest lab for you.
Additionally, Tamra Jackson, Extension Plant Pathologist & Corn Specialist at UNL, has posted a video talking about corn ear molds as well as a newsletter explaining corn ear molds. The video can be viewed at http://marketjournal.unl.edu/103009, scroll down to corn ear mold/Tamra Jackson to view the specific video. The newsletter can be found at http://cropwatch.unl.edu/web/cropwatch/archive?articleID=1904835.

Friday, October 30, 2009

Updated Mountain Pine Beetle Information

Irene Shonle, Director of Gilpin County Extension, in cooperation with the Northern Front Range Mountain Pine Beetle Working Group, has just put together a 12-page newspaper-style publication on mountain pine beetle (MPB). It is a pretty thorough, up-to-date document on what homeowners can do with infested trees. It also includes information on the likely transition to the Ponderosa Pine zone and how treatment options should differ in lodgepole and ponderosa. The contact information contained in the document is specific to the Front Range of Colorado, but the rest of the document is applicable anywhere.
If you are a home- or land-owner in an area that is being affected by MPB, this publication will provide the best research-based information available. The link below will open up a PDF file with the document that can be printed or saved to your own computer for future reference.

Mountain Pine Beetle Infomation (PDF)

Monday, October 26, 2009

Update on 2008 wheat virus survey

Last week, the blog mentioned the wheat virus survey from 2008. http://www.apsnet.org/online/feature/virus/ is the url for the entire article, but I thought I would post a bit of the pertinent data here. "A total of 754 wheat samples were collected in the nine Great Plains states during the 2008 survey (Table 1). Due to various factors a small number of the samples were not tested for all five viruses. Therefore, results were standardized and presented as the percentage of the plant samples tested for each virus. The number of samples from each state varied from 21 to 307 (Table 1). The predominant virus detected in each state was WSMV, and this virus was detected in 47% of the plant samples (Table 1). WMoV (19%) and TriMV (17%) were the second and third most commonly detected viruses (Table 1). The aphid-transmitted viruses BYDV-PAV (7%) and CYDV-RPV (2%) were infrequently detected compared to the mite-transmitted viruses. Co-infection of a single plant by WSMV plus WMoV (13%) or WSMV plus TriMV (13%) was the most common co-infection detected. Five percent of samples were co-infected by all three mite-transmitted viruses and only 0.4% of samples were co-infected by both aphid-transmitted viruses." The table referenced is available at the url previously listed. Hopefully by next spring, we should have the data from 2009 compiled and ready for publication.

New Service at the Diagnostic Clinic

For all those interested in having plants or soil tested for herbicide damage, I have found a lab that can test for almost any type of chemistry. The one thing needed is that we need to know what chemistry to test for as they don't have a 'chemical screen'. It is rather expensive for this testing (and they only test for one chemistry at a time), but if you or your client needs this information, it may be worth the cost in order to have a definitive answer. Here at the diagnostic clinic, we can ship your sample to the testing lab, invoice you or your client for the cost of testing and shipping and forward the report(s) to either you or your client.

If you have any comments or would like answers to frequently asked questions, please feel free to leave a message. We'll try to get you an answer.

Monday, October 19, 2009

Hi! Welcome to the newly created CSU Plant Diagnostic Clinic blog. In an attempt to use more of the available technology to increase our visibility and to keep folks informed about old and new plant problems, we have created a blog. Our hope is that we will be able to post about once a week or so on diseases/insects that we are seeing in the clinic as well as new information that may be of use to our clients.

This time of year is generally considered our slow time so we are slowly catching up on data entry and getting ready for our winter fungicide trials. Again this year we will be actively seeking participants for our winter wheat virus survey. Growers, extension agents, and crop consultants are encouraged to send symptomatic plant material to the Plant Diagnostic Clinic for free virus screening. The viruses we are screening for are WSMV, CYDV, BYDV-pav, WMV (formerly HPV) and TriMV. If you have a request for any other virus testing be sure to let us know and we can probably accommodate that request. As always, we appreciate any information that you can send us with the samples (location, variety, name of submitter, etc.). The data from the 2008 growing season was compiled by Mary Burrows at Montana State University and published in Plant Health Progress. Mary is again compiling the data for the 2009 growing season and will be publishing the results soon. Your help in providing samples for testing is appreciated.