cc  >> Thank you for watching  Wednesday Nite @ the Lab  tonight.  Tonight we will be having Paul  Esker, from Plant Pathology, and  the title of his seminar is  "Impact of Diseases on Field  Crops and Food."  Dr. Paul Esker is a native of  Weston, Wisconsin.  He graduated from the UW in 1998  with a Bachelor of Science in  genetics and bacteriology.  He attended Iowa State for his  Masters degree in plant  pathology, and also has a PhD  from Iowa State in plant  pathology and statistics.  After his postdoctoral position  with NSF that had him traveling  between Kansas State, Iowa  State, and the Universidade  Federale de Rio Grande de Sol,  he joined the Department of  Plant Pathology at the UW in  September 2007.  Paul currently holds an  extension research appointment  studying diseases of field  crops, small grains,  and forages.  And now I present to you  Dr. Paul Esker.  (applause)  >> Paul Esker: Thank you.  Good evening, everyone.  So what I'm going to be talking  about tonight is a little bit on  impact of diseases on field  crops and food, emphasizing  examples from Wisconsin that  have happened over the past  couple of years in particular,  because I think a lot of things  occur each year that we don't  think about and we hear about it  after the fact, and really  trying to get our heads around  it. 

 When we deal with impacts on  field crops, and I'm going to  expand to small grains also, so  we can touch on wheat a bit,  what we're really thinking about  is a quantity issue, so what we  would define as yield loss, and  also a quality issue.  In actually two of our examples,  quality is more important.  So an example from wheat and an  example from corn in particular.  So we're going to kind of walk  through some things that way.  But before we really get into  it, just think for a sec, to put  in perspective of where we're at  on dealing with field crops.  I know many of you are probably  well aware of the situation in,  say, 2007 with the food security  related issues.  But to put it all in perspective  a little bit, what did you have  to eat today?  As you think about that,  realistically, what you had to  eat today had some form of an  ingredient either from corn,  soybean, or wheat.  Maybe more interestingly, it's  what you don't know about how  some of these products are used  in that food production pipeline  that comes together.  We're going to introduce that a  little bit and then take it from  there.  So sort of the outline for the  talk, and I have an extension  appointment, so I'm used to a  very informal approach with  these talks, we're going to look  at how these three crops, corn,  soybean, and wheat, fit on the  Wisconsin agricultural  landscape. 

 Secondly, we're going to talk in  a general sense about plant  diseases and their effects on  these crops, but we can broaden  that out because really we're  talking about some variety of  things.  Lastly, sort of the latter part  of the talk is going to focus on  three very specific examples of  recent note in Wisconsin.  In wheat, we're going to touch  on fusarium head blight.  We're actually going to broaden  that out a little bit to what  happened in some ways in the  region the last year, in the --  red winter wheats.  In corn, for those in the state,  as you know, last year much of  the crop didn't come off the  field very early.  We dealt a lot with questions on  ear molds.  This was a region-wide issue.  Both of these first two examples  bring up questions about  mycotoxins, so it's a very  natural way to link these  together somewhat.  And then soybean last here.  We had a lot of problems for the  first time in about five years  with sclerotinia stem rot, also  known as white mold. 

 And this is actually a disease  that not only affects soybean,  but it affects many of our  processing vegetable crops in  this state as well.  So there's bridges with what  we're talking about tonight to  some other areas.  So some uses of these crops to  kind of think about it.  The majority of corn is grown  for grain, so about 90% to 95%.  Wisconsin is the number one  producer of corn for silage.  This shouldn't come as a shock  when we look at our primary  dairy business in the state, but  on the whole it's about 5% to  10% across the US.  This is probably just a low  number.  There is documented about over  3,500 uses for corn.  So it's not only a product that  we use for food, but it's also  one we talk about in fuel and  also fiber.  Some examples of what we might  think about. 

 Canned corn, baby food, and baby  food here isn't just mush corn,  it's ingredients and texture in  that.  Hominy, puddings, tamales,  anybody who's enjoyed those at  holiday time would understand  that quite well.  On the industrial side, we can  think of a lot of things, and  plastics are one.  We get a lot of our materials  shipped to the lab now, the  packing materials is actually  corn.  And what's interesting about it  is when you're done with that  packing material, you can  actually put it in water and it  dissolves.  So you're not building up all  these byproducts from packing  materials that way, so they're  biodegradable.  Insulating material, adhesives,  paints, pastes that are used as  binding product.  Some of the misnomers.  Corn flakes are only partially  corn flakes as we look at that.  To give you some idea, and this  is one that comes up when we  think about food security. 

 If you look at one box of corn  flakes, about 8% of that weight  is corn.  So in the box, it's still a  small amount, relatively  speaking.  Less than 5% of that price  reflects the corn price.  So on the whole, it's all the  other aspects of the food  production process that adds  price to some of these products.  In a similar light, we can look  at soybean.  Corn is used predominantly  domestically, it is exported.  Soybean on the other hand is our  number one export field crop in  the United States.  The Asian market is very big for  it, something we deal with on  the whole.  Soybean is primarily used as an  oil and also for meal, so  shortening, margarine, cooking  oil, salad dressings.  All of these have some sort of  soy-based product. 

 Breeding for soybean often  emphasizes looking for oil as a  defined content in what the  breeding process wants to be.  High protein meal, or soy flour,  is also something we use it for.  Vegetable protein in many food  sources.  Industrial paints, varnishes,  inks.  Many products that way.  Just to give you an idea, if you  don't think you eat soy, it's  not just tofu.  Lecithin, which is a fatty acid,  is an extract from soybean and  is an emulsifier and lubricant.  So most of us have probably had  a candy bar.  This is actually the binding  agent that helps hold chocolate  and cocoa butter together in  candy bars.  So you can see it's a diverse  use in the food system. 

 So corn and soybean have a  pretty broad use.  If we contrast that a little bit  with wheat.  This is actually more or less  primarily a human food crop.  About 20% of the world food  calories come from this.  Rice is the number one staple in  many places, this is closely  behind.  What makes wheat important in  the food chain is, gluten  protein enables leavened dough  to rise, so any bakery items  that we deal with, this is why  wheat is so popular.  It's also why people have an  intolerance to wheat a little  bit, they can't handle the  protein.  Wheat is used differently in  what we term different food  classes for how we would deal  with wheat.  So here there's some shorthand  I'll use.  I'll explain it a little bit  because this is a function of  when wheat is in the ground, and  we'll look at it specifically  for Wisconsin versus some of the  other areas. 

 If you think of breads, the two  primary types are hard red soft  wheat or hard red white wheats.  These are the wheats that often  come from the Great Plains, like  North Dakota, South Dakota.  Pastas come from Durum wheat, so  if you look, if we go west from  Wisconsin, most of the Durum  wheat is grown that way.  I went to Iowa State as an  example.  Barilla pasta has a large  processing plant there, because  it's well-established on the  train routes to get wheat in  from the western Great Plains.  Soft red winter wheat, which are  what is predominantly grown in  Wisconsin in this part of the  US, cakes, biscuits, and pastry  flours.  And lastly, soft white wheat,  which are locally, the closest  probably grown is mostly in  Michigan, pastry flours, the  shredded, puffed breakfast  foods, so some of the shredded  wheat you would find in the  store.  One of the difficulties with the  soft whites, however, is they're  prone to what is called  "pre-harvest sprouting," which  means they actually sprout in  the field and they have no  market that way post-harvest,  especially when we're talking  about a food source.  So these are some of the sort of  uses of wheat, corn, and  soybean.  They're slightly different, but  they slightly have some  similarities that way. 

 To give you a backdrop, wheat in  Wisconsin was the number one  crop, if we go back all the way  to 1860.  If you think about the movement  of wheat across from the east to  the west, as you established a  new area this was an excellent  crop to go in that way.  29 million bushels, as you'll  see, coming up with our data.  We're nowhere near that level at  this point, and so to put it in  perspective, here's the annual  production of our three main  crops.  We break this out, the blue line  is from Wisconsin.  We put US data in it for  comparison, because there are  some differences in our  production.  To orient everybody a little  bit, if we look here on the  Y-axis to our left, harvest  acres in the US.  On the right are harvest acres  in Wisconsin.  There are some parallels.  To kind of look over the last 30  years, corn production in the  state mirrors national trends  over time. 

 And that's actually at the  highest level there, those are  the circles.  You can see blips going up, but  when national production goes  up, Wisconsin production sort of  follows.  Typically in a given year with  harvest, about 3% to 5% of the  US corn crop would be from  Wisconsin.  In terms of soybean, that's our  upside-down triangle a little  bit.  Nationally, you can see some  parallels.  The gap between the US  production and a relative metric  and Wisconsin, less of the US  acreage, about half a percent to  2% per year, but as you can see,  they still mirror in trends with  a significant increase coming in  the mid-'90s with some changes  in technology, such as --  soybean.  Wheat on the other hand has  shown an opposite trend in the  United States.  If we look here from about 1980  with a closed square, over that  30 year period, we're actually  seeing a decrease in production  and it's going down again in  2010 for some very specific  reasons with the late harvest we  saw in corn and soybean, as well  as some concern with scab in  many of the soft red winter  wheat areas.  In Wisconsin, while it looks  relatively flat, if you put it  in a relative scale, since about  2000 we have almost doubled our  acres back in the state.  We're right around 300,000. 

 So relatively speaking, we don't  have a large proportion of the  US crop, less than a percent,  but I think what you'll see  coming up is, the value of that  crop is actually fairly  significant to the growers in  this state.  In terms of annual yield, and  this is one of the questions  that comes up with regards to  the impact of diseases because  it will influence production  practices.  If we look here, yields in  bushels per acre.  Corn is significantly higher  than our other crops, that's  normal, but what you should  focus on over the last 30 years  is you see a continual trend in  a positive direction.  Corn yields continue to break  records even with the late  harvest last year in much of the  corn belt.  Yields were at record levels in  many of the states.  I believe in Wisconsin we had  our second largest harvest, if I  remember correctly, on average.  Soybean yield mirrors again US  and Wisconsin trends.  But if you look at those lines,  they're fairly flat, and this is  a question producers ask.  Why should I grow soybean when I  see the yields going up in corn?  That has an impact on how we  manage the disease, because it  will change some of the  production practices. 

 One of the flips we see in  Wisconsin, our wheat production  and the yields we can get coming  off those wheat acres are much  better than the US average on a  whole.  We don't have as much of the  acres.  We're not as prone, with some of  our production, to drought in  many situations.  Our major wheat acres are in the  southern part of the state to  the eastern part.  You get a different microclimate  occurring out there, so there  are some variations out there,  but it also raises some concern  for the diseases.  We were actually out in the  field the past couple days,  we're already seeing some  evidence of -- diseases a little  bit earlier than we had in the  past couple years.  Production value, and this is  one that does drive the  economics of everything.  If you look there, it's quite  bouncy.  It takes into account some of  the drought years and the flood  years that we've seen in the  region.  If you look at corn, since about  2005 we've seen a fairly  dramatic increase in the total  value. 

 This has been driving some of  the questions and what it means  is, we're seeing more corn on  corn acres in many areas.  From a pathology perspective,  that's something we're concerned  with, from the risk perspective.  Soybean acres and the production  value are trending up, but  they're not as dramatic.  So again, these questions come  back of, what crops should we  put out there?  At the end of it all, wheat is  still a significant value on the  whole.  Yes, sir.  >> (inaudible)  >> Esker: So, the question is,  the sharp spike that's  about 2007 in the corn  price, was that a function  of ethanol?  That was the period when we  heard most about food security.  We saw the largest increase in  ethanol plants and production.  We also saw a dramatic increase  in the number of acres.  So in 2007, we were  approximately 85 to 90 million  acres in the United States.  A couple factors were driving  that out. 

 It's sort of steadied back down  to what we would expect.  The value stayed high, the price  stayed high a little longer, but  the acres have come back down  accordingly.  So it's a function both of  increase in acres, demand for  corn across these different  areas, as well as the price  going up as demand changed and  shifted, so it's a couple  factors.  A very good question, though.  Again, what you see in Wisconsin  on the whole, about 3% to 5% of  that annual production, so our  production mirrors the  economics.  Soybean and wheat, if you  remember the percentages we were  talking about, on the top end,  we can often see annual  production that's a larger, even  thought it's small, it's larger  in the US because our yields can  be better oftentimes than the  national average.  So there are a couple factors  driving that.  What does this all mean?  And I think the question that  was just asked ties into it.  There is increased volatility.  A good friend and colleague from  Scotland was just floored when  you look at a year like 2007,  how plastic production can shift  going up tens of millions of  acres in one crop, that has to  come from somewhere else. 

 When you talk to somebody from  Europe where there's a much more  stable market, this is  interesting from that respect.  Corn yields continue to increase  faster, leading to questions  about what we should be putting  in the ground.  And nationally, wheat production  is trending downwards.  So really, our tie to the  disease aspect, this is for a  couple of reasons.  In this current climate going  into 2010, a lot of large acres  not planted in the Midwest in  2010, we had late harvest corn  and soybean, and we also had  fusarium head blight, and I'll  be passing around some things we  look at to rate for things like  scab accordingly, and I'll talk  about that in more detail.  In terms of bringing the  pathology into this, the shifts  raise some of the questions in a  general sense.  What we do is, we study the  causes of disease due to a  pathogen, much like we get  infected as humans.  We look at it on various levels.  We're talking here on a  population scale, so in a field  setting, but we can look at it  at a molecular, cellular, and  whole-plant sort of level.  We're trying to understand how a  plant responds, so the data we  look at to try to provide the  best information out is based on  this. 

 How pathogens move from field to  field or from plant to plant is  an example.  The environment is one we have  little control over, so some of  the diseases we're talking about  are directly affected by that  environment.  And also then, what can we do to  manage these to keep those  yields up or pushing the  envelope a little better?  We deal with different types.  All our examples today are fungi  but these are organisms that are  usually filamentous, or  threadlike and heterotrophic.  Bacteria are ones we're more  familiar with, probably many of  us on the human side.  These are microscopic organisms  that are usually single-celled.  Viruses are another one that  come up, so again, some  parallels to the human sides.  Some microscopic organisms that  are obligates, so they need a  host at least to keep alive.  And lastly, we deal with  nematodes, and there's nematodes  in humans, also, so  non-segmented roundworms, these  are animals.  So as you can see, we have very  different scales of interactions  among these pathogens with the  plants that we deal with. 

 To put it all a little bit, to  give you an idea, if you hold  out your hand and think of just  a handful of soil, so you're  gardening at home.  In that one handful of soil  there's anywhere from  300 million to 50 billion  bacteria,  500,000 to 100 million fungi,  1,000 to 10,000 nematodes,  and about 0 to 2 earthworms.  There's a size issue, of course,  with the earthworms.  But there's tremendous diversity  in that soil.  Not all of these organisms  affect plants adversely.  There's complex interactions  going on, but really what we  deal with on the pathology side  is to try to understand those  that do cause the diseases.  But what we do to manage those  will have an impact also on  what's already there, so it's  sort of a balance between  everything.  Disease does not just occur  because we have a pathogen and  we happen to have a crop there,  or a host there.  The disease triangle concept is  one we teach in all our  introductory courses and we  teach in our extension program.  We have to have the host, we  have to have the pathogen, but  we also have to have a favorable  environment. 

 And this varies by the diseases  we deal with in field crops.  So when all three really come  together, that's when we get  disease.  So here one is missing,  everything breaks down  accordingly.  So we tackle managing these  diseases on all levels.  We group diseases in a variety  of ways, so we're going to be  talking about some things we can  see typically in the field  tonight, but they're based on  symptoms which are local or  systemic.  Sometimes we can't see them with  our naked eye, so we have to use  other methods to look at them.  Might be based on the plant  organ affected, so it could be  the root, which means visually  in the field, guess what, we  don't see anything going on,  it's all happening underneath.  Tubers, if you remember last  year, we had issues in potatoes  with late blight coming back  into the state a little bit.  That has a direct affect on  harvest material.  Stems, we will talk about one of  those diseases tonight. 

 Leaves and heads, we will also  talk about some of the head  problems and how we define it.  Based on the type of plant,  vegetable crops, field crops,  ornamentals, they have some  similar characteristics, but  some very different ones as  well.  And based on the type of  pathogens we've already  described.  And interestingly enough in the  area we're all moving into, it's  how do these different pathogens  work together or work against  one another in this whole  process?  What are the impacts?  So really that's kind of the  driving question tonight.  In a classical sense, what we're  trying to do is understand loss.  And loss is not just always  quantity, but we're looking at  the relationship between the  attack by harmful organisms and  the resulting yield, or yield  loss is maybe more apropos of  crops.  So what it means is,  disease-yield relationship, so  the effect of the disease on  that plant is a part of this  whole concept.  Because it's not always a  disease.  Insects do the same thing, weeds  can compete in the same way,  abiotic factors, drought, these  all drive that.  What we will be talking about,  quantity, so physical reduction  in amount, but maybe more  importantly is the quality at  times, for the impact on food. 

 Because you go to the grocery  store, blemish on a fruit, you  may bypass it.  Not that there's anything wrong  with that fruit, it's a personal  choice on some level, but you're  looking at the quality aspect,  so there may have been something  going on.  In the field crops, we're as  much or more concerned with  toxins in our food supply.  And that's something we do deal  with occasionally in the state,  and a couple of our examples  touch on that.  One of the key points is we have  to estimate this taking in the  cost management.  Put yourself in a grower's  perspective.  If the cost of management is  more than the crop's worth,  you're probably not going to do  anything, so there is a  competitive balance and  realistically, this is my  disclaimer, we really don't know  how to estimate a lot of this in  terms of loss.  We try our best, but you isolate  single disease host systems, you  miss a lot of other things.  So it is a complex sort of set  of interactions that we have to  deal with in this whole concept.  Management takes on many levels  and we'll see some of those in  our example. 

 Exclusion, so we can quarantine  to keep it out, or inspections.  Actually our department of  agriculture handles the  inspection side.  We can try to eradicate or  reduce inoculum out there.  This may or may not work.  If you're talking about the  number of acres we were talking  about already, for these three  crops, that's probably not  realistic for over 5 to 6  million acres.  Host resistance is one, but it  varies by some of the example  we'll touch on.  Biological control, so using  another organism against it.  Chemical control such as  pesticide, like a fungicide,  falls under that.  And often we have to combine  strategies into those situations  to make it most effective.  What are the conditions in our    field crops that are changing  that influence or favor the  occurrence of a disease?  And our three examples will  touch on that. 

 One is hybrid, if we're talking  about corn or cultivar  susceptibility.  You put something out there  that's susceptible, you're run  down, the virus particle infects  you, you get sick, it's the same  sort of thing.  If you're in a weakened state  already, you're more likely to  become sick.  We do see an increased  production of corn following  corn.  Those 2007 spikes in production  and the economics are driving  some of these decisions.  Growers are asking questions.  I can get more bang for my buck  growing corn on corn.  That can be a negative.  We put more residue out there,  we have some other issues that  way.  Luckily, in many areas of  Wisconsin, we have a very  diverse cropping system between  the different crop types. 

 This can help us, or works in  our favor.  We don't talk about alfalfa  here, there's another crop we  can add to the mix on the field  crop side.  Conditions that also favor, what  we're seeing with some of our  examples.  High likelihood of inoculum in  many fields.  A couple examples, sclerotinia  stem rot of soybean.  I'll pass around what that  inoculum sort of looks like, or  the survival structure.  Soybean cyst nematode is one.  This would be one of these  working underneath that we may  not see above ground until the  effects have taken hold.  From an environmental  perspective, increase in  no-tillage or minimum tillage.  Good for erosion control, but it  increases inoculum. 

 Many of these pathogens have to  survive from season to season on  a host plant and so the inoculum  in that field provides a source  of inoculum for the next season.  And one of the interesting  things in a climate like  Wisconsin, this residue doesn't  break down very fast.  So you can go out two years  later and still see a lot of  corn debris in certain fields  depending on that hybrid.  So let's really, this is what we  want to talk about and the  impact on food in various ways.  Some specific examples.  These are all examples that have  occurred since about 2008  through the last year.  An example from wheat, an  example from corn, and I'm going  to pass around some of these.  With the corn, I would advise  those in the audience maybe not  to breathe too deeply when you  look at these samples, just from  the mold deposit.  And sclerotinia stem rot or  white mold in soybean, and I'll  pass around a plate that shows  you what we look for that way.  So fusarium head blight damage  might be a little difficult to  see. 

 What we look for as we come into  maturity is actually a bleaching  of the heads.  So I have some example here of  just what a wheat head would  look like.  We'd actually be looking for  pinkish discoloration or  bleaching on those heads.  That's an indicator that scab's  in that field.  Going back two years, we had a  lot more reports.  We actually had dockage at the  elevators for scab.  Just this past year in Illinois,  Kentucky, down in some areas in  that same production, soft red  winter wheats as we grow in  Wisconsin, areas with high  mycotoxin contamination.  So a really large effect.  From a grower's perspective, the  loss is not only in terms of  yield, but it's a quality  effect.  So they can get docked for a  couple things. 

 Low quality in test rates, high  mycotoxin contamination.  That grain can also be rejected  outright.  So there's an impact from the  baseline all the way through.  Our concern in the food source  is the mycotoxin aspect.  Little backdrop on winter wheat.  In the state we planted already  last fall.  What's coming out now is  actually ahead.  We've had very nice spring  conditions, temperature and  timely rainfall, so we're ahead  of the curve.  We're really in this period  right now of emergence, pre-flag  leaf emergence.  What we're going to be talking  about with scab is towards the  latter part of the growing  season at the end of the day. 

 So we are monitoring everything  at this moment to try to get a  grasp on what's occurring in  other ways.  This is a lot of material to  digest, we're not going to focus  on it.  But to tie some things together  on fusarium head blight.  There is an inherent link  between wheat and corn in this  situation.  The same pathogen that can cause  scab can cause a stock rot and  ear rot in corn.  So the rotation of those two can  lead to that continual sort of  disease risk out there.  What I am going to pass around,  which ties into some of what we  term as tombstone kernels, or  bleached kernels, I have some  examples here for people in the  audience that you can look  through that give you some  differences in sort of the  bleached appearance in the  kernel.  Why that's a concern, because  it's a quantity issue, you have  lower quality of the grain, but  it's also an issue because  that's what tips us off to that  we may be at risk for some  mycotoxins.  Compounding that is the fact  that the appearance of symptoms  on the head does not necessarily  correlate very well with  mycotoxin, so there are  differences in the wheat  varieties.  We use these for grading in our  own programs, so there's  different percentages in each of  the plates being passed around. 

 For infection to occur, and  we're going to look at some maps  how we try to predict the risk,  we need to have a susceptible  variety.  More or less in our wheat crop  in the US, nothing is completely  resistant to scab.  We have to have inoculum present  at flowering, that's a critical  timing.  And we have to rain, high  relative humidity, and  reasonably warm temperatures.  So for us, we're talking about  June when all this takes off.  And so by building up inoculum  in there and some of the links  with corn, this is something if  the weather comes into play at  the right time, can put us at  risk.  Flowering here, some examples of  it.  Why this is critical is from a  management perspective, for a  grower, most of the fungicides  that are currently labeled in  wheat, when we see flowering  there, are no longer labeled for  use.  Which means they have fewer  options.  Plus we have a very tight window  to do everything. 

 Flowering occurs over about  seven days, that's about the  same period you have to make a  decision for management.  So one of the reasons scab, when  it occurs on a wide scale, is so  problematic and of concern from  the mycotoxin perspective, is  that there's very little a  grower can do if they can't get  out into the field.  How we deal with this in  Wisconsin.  There is a winter wheat variety  trial program that we try to  provide information to.  This is run through the UW  Agronomy Department.  This is multi-location.  This just shows you how kind of  data are tabulated.  What we try to do for the  growers to improve their  knowledge of selection is, we're  working in a way to rank the  relative merits of a variety  against some of the reactions.  So what we show here is what's  termed fusarium head blight  severity.  So if we look at a wheat head,  we actually go out and we count  the number of kernels on that  head that are infected to give  you that measure. 

 And what you'd be looking for as  a grower is everything in this  lower quadrant.  On the yield perspective it was  a high-end yielder.  From the disease perspective, it  was relatively low.  We use a couple types in the  state based on what growers are  producing as references for  them.  Some are public, some are  private, some have high  resistance.  And so what the grower can take  away from this is, they can  compare what they might be  growing in their field to help  reduce some of that risk.  Now, similarly, what's being  passed around is what we would  define as fusarium damaged  kernels, to try to rank those.  We do the same things.  And you can see examples of  varieties that do well in the  field, but after harvest they  break down a little bit.  So some varieties do shift in  what we see there, and so the  grower has to take that into  account. 

 Now, there is a federal program  for mycotoxin testing for many  of the states with this.  One of the difficulties is the  time delay to get those results  out in a timely fashion.  It often takes about a year to  run so many samples from so many  states with a few defined labs  that way.  So this is real-time data that  we try to provide to growers to  move forward.  There's also forecasting, which  is handled through Penn State  University.  This is a weblink if you're  interested in looking at it.  Just to illustrate what we try  to do with this to provide  information back to the growers.  You can see during what would be  our critical flowering periods  often in the state, this is a  very basic low, medium, high  risk system that's based on  weather data, so the humidity in  particular, relative humidity in  the area.  So a grower can go in and look  at if they're under a high risk,  and that may help that producer  hedge their bets in terms of how  best to manage for this disease.  In terms of mycotoxins, and  we're going to bridge here with  our corn examples, these are  toxic substances produced by  fungi or molds that grow on  grain, feed, or food, anybody's  left something in their  refrigerator knows that very  well. 

 That's not necessarily a  mycotoxin risk.  There's about 400 to 500 known.  We're going to focus on just a  couple of them in particular.  And like I've already said,  presence of mold doesn't mean  you have a mycotoxin, and that's  the difficult thing here from  the food perspective is, how do  you test all this grain coming  through?  And that's a challenge for the  federal government, it's a  challenge for state governments,  and also for local producers.  Similarly, no mold does not mean  you may not have mycotoxins, and  we can see examples where that  occurs.  We're often focused on things  that are caused by what are  termed fusarium species.  One that also falls under that,  but it goes by a different name,  gibberella zeae.  Aspergillus is one we won't  touch on a whole lot because  it's usually a hot-dry and we  haven't seen always those  conditions in some of these  examples.  The main mycotoxin we're going  to focus on is vomitoxin, or --.  That's the most common one we  deal with and we'll show what it  means in the food source. 

 Zearalenone and fumonisin B1 and  T2 are also ones that have come  up more on the corn concern.  Aflatoxin, from a human  perspective, this is a problem  in Africa quite largely.  Affected by hot and dry  conditions for this organism.  It's one we occasionally see,  there are blips that come up in  various forms, but the last  couple years were focused more  on the upper ones.  What does that mean in terms of  FDA thresholds?  So if we look at this, we're  focused on use as a human, bran,  flour, germ, intended for any  use in a human, that's only one  part per million, so typically  as you know, the lower  thresholds are for human use.  But cattle is a big component of  this process as well, and you  can see that changes by what  we're dealing with.  If we're talking about grain  byproducts for ruminating beef  and feedlot cattle, again that  could end up in our food supply  in different ways.  Greater than four months old and  chicken can't exceed 50% of that  diet, ten parts per million is  the threshold.  So this grain is tested just as  well.  In swine and other animals,  again it varies how much of the  diet, the threshold's somewhere  in between, because different  animals have different reactions  to these mycotoxins and so  that's something that goes on. 

 Yes?  >> (inaudible)  >> Esker: Typically no.  So if we're talking about a  lactating animal, like a dairy  cow, typically why you don't see  as many problems with some of  this is their innate ability to  kind of bypass that.  So the ruminating process that  they go through helps to kind of  destabilize it.  We would not necessarily see it.  Now, from the animal's  perspective, if you feed a high  dose, there's a negative effect  that way and that becomes as  much a political sort of visual  issue in the food supply chain  for some of this.  Really, if we know it's going to  a human source, and much of the  wheat, in particular, is more or  less a human source, this is a  large concern that way.  The grain for ruminating beef  feedlot cattle or swine, we're  talking often about a corn grain  being fed in that, some  different situations that way,  as well.  But a very good question.  To tie into that, the late  harvest, and I will start  passing around so you can  actually have a close-up.  Feel free to open the container  for those in the audience. 

 There isn't a lot of dust  particles, but it is something  you take into account.  So that's a second side,  actually, of the process, is not  just the food supply chain, but  also the human health exposure  of dealing with a lot of molds  out there.  To give you an idea of what a  good corn coming off the field  should look like, there are some  comparison contrast that way.  This is what we'd like to see in  most years.  Not always the case with what we  deal with.  So here are some examples, and  we'll touch on the main ones for  the state.  This was a real concern this  past year.  2009, late harvest, many  questions about ear molds in  corn, not just in Wisconsin  again, but across the region.  For example, all you have to do  in any internet search engine,  and I'm not going to promote  Yahoo! to Google,  whatever you prefer, just  type in something like "ear  molds and corn and 2009" and  just see the number of articles  that talk about this.  That would put it in perspective  for you. 

 Because of that, there was high  concern that the moldy corn  that's being passed around in  the audience here today would be  contaminated with mycotoxins.  Now again, if you type in a  slightly different search, which  I was doing the other day, I  started to actually hit on legal  documents in areas of, say,  Indiana and Ohio where this is a  concern this past year.  So there are some ramifications  that way.  Because of that, there was a  state-wide survey through UW  Extension.  The results are actually posted  on the UW Extension website  listed here.  Just to kind of get a grasp on  what we're seeing in the field  necessarily.  What we can see here is our  couple dominant types and we'll  go through more details on a  couple of them.  Cladosporium and fusarium as an  example were the most  predominant.  These came from about 32 or 33  of the counties across the state  in this survey.  We do see some other things  popping up, although very  infrequent in that respect, so  we're going to focus on the  first two in more detail. 

 Fusarium ear rot.  For those in the audience  looking through, you probably  could see some of this  symptomology on those ears.  Different species of this cause  it.  These are different organisms  from what causes scab in wheat,  but we will talk about the  overlapping one.  They vary, so if you looked at  those ears, not all of them were  uniform.  They'll vary on the genotype,  the pathogen, as well as the  host, the environment, last year  we just stayed cold, disease  severity in the field, was there  lodging in the field that put  the ears down on the soil line?  They're a whitish-pink to  lavender growth on the kernels,  which you probably can see in  the samples being passed around.  A starburst sort of symptom  where it just looks like a  starburst on that kernel grain,  is another common one.  Usually associated with physical  damage, and so we had some hail  in the state in 2009, I saw  results from Iowa where they had  multiple hail events, very  different results coming out.  And a key one here, like we  talked about in wheat, you can  have asymptomatic, so no  symptoms on the kernels.  These are the ones in most years  what we would be dealing with. 

 Gibberella ear rot, this is the  organism that ties us together  back to wheat a little bit in  that process.  In the ears being passed around  you probably could see that  whitish-pink color at the tip,  very tight looking almost, like  a glue on there.  This is the same organism that  causes scab or fusarium head  blight in wheat.  That's a concern we deal with.  There's another name for it,  again it kind of grows tip  downward.  If infected early, the entire  ear may rot and have pinkish  what we would term mycelium.  But the husks will adhere  tightly.  These are the sort of ears, if  you were in a field, you'd go to  yank them off and they seem to  not want to come with you.  They're very bound to the plant.  It's rare to see an entire ear  colonized, although if it's  infected early it just never  develops normally, so in theory  it's the entire ear affected,  but the ear is very small. 

 Cladosporium ear rots, the ones  that have the black  discoloration on there, this was  one of our more predominant  things we dealt with.  Couple different species deal  with it.  Darkish, greenish black,  blotched, or streaked kernels.  It does look similar to another  pathogen we deal with, although  this trichoderma, which is a  rapidly growing organism was  found mostly where there was  hail damage and not in  Wisconsin.  Often scattered across the ear.  If you were brave enough to kind  of touch it, actually that kind  of growth on there wipes off  fairly easily, so what it means  is there's another stress in the  system to affect it.  And it's often associated with  injury.  This past year, frost damage.  We had early freezes in 2009 in  September.  With the cool conditions, that's  what brought everything sort of  together. 

 A lot of different things were  noted that we deal with.  All the red Xs up there, those  are organisms that do not cause  mycotoxins.  The fusarium species can cause  mycotoxin.  Monitoring over the winter, as  indicated, we haven't had a lot  of reports, which is a good  thing.  But again, within a diversified  crop that can go for both food,  fuel, and fiber, it is something  we keep in mind.  Actually many ethanol plants  have a threshold that's even  lower for testing because that  process concentrates mycotoxin.  These are very stable components  in that system.  So we pay attention to this  because it has effects in the  food system, but also elsewhere.  Our last example, and I'm going  to pass around three different  plates so you can kind of look.  You can differentiate the  soybean seed to what we'll be  talking about, the survival  structure on this, to give you  an idea. 

 Sclerotinia stem rot, white  mold, is something that affects  soybean and other things.  These images may be a little  difficult to see with the lights  in here tonight, but what you  actually see is fields that look   dead way too early.  So I'm talking here late August  in our production situations.  The image in the middle, again,  it's a little difficult to see  in the audience.  That field is more or less brown  looking and it was a fence line  to fence line field.  So what this translates from a  quantity perspective, fields  that are heavily infected, you  can see large reductions.  So a field that may normally  yield 40 or 50 bushels could  yield 10 or 20.  And this is a concern in certain  areas and something we deal  with.  Driven as much by weather as  also inoculum that we deal with.  Again, July 2009, how many wore  shorts and that, outside a lot  last year?  Not too many, it was the coldest  on record. 

 So white mold was very actually  observed in a lot of areas of  the United States when normally  that would not occur.  What does this mean?  It's an organism with worldwide  distribution, has a very wide  host range.  So crops that are relevant to us  in Wisconsin, soybean, snapbean,  pea, there is some sunflower, if  we go to the Dakotas, that's a  big one, canola, lentil,  chickpea.  The leguminous crops are things  we deal with.  So it has effect across a broad  sort of food source for many of  us.  What's being passed around is  the survival structure to  differentiate it to the soybean  seed.  The top is actually the  apothecia that we can look for  during the season as an  indicator of risk.  At the bottom, this is actually  a split stem sample.  So the pathogen, when it  infects, can actually colonize  the whole stem.  What you're seeing there is  lab-grown, lab-raised sclerotia,  so they don't look quite the  same as the field. 

 But in a soybean stem you can  often see the whole thing  infected and colonized, and  that's how the organism survives  for a long period of time.  These are very stable  structures.  The disease cycle a little bit.  It's another disease much like  our scab in wheat that is tied  to that changeover from  vegetative growth to  reproductive growth.  Really we're talking about  flowering here, where the spores  are released.  They can't escape the canopy,  they get into the flower, they  cause infection.  You can see symptoms inside,  outside that soybean plant,  inside pods.  What it means is, when you  harvest, you just have these  black survival structures  instead of actual grain.  The effects can be dramatic in  some areas.  On the whole we saw soybean  yields last year go up in  Wisconsin, so it wasn't  everywhere. 

 Factors that influence.  It is one of the more complex  diseases we deal with.  We'll just kind of put them out  there.  What a producer does can have a  dramatic effect on the risk.  And we'll look at it more  graphically.  What we tell growers, it is a  disease of high yield potential.  So conditions that are good for  growth are also good for this  disease.  To kind of put it a little bit,  that black survival structure,  these survive in the soil line.  What happens around flowering  is, as the soybean canopy  closes, the environment in that  canopy changes quite a bit.  If we have high density of  inoculum or the sclerotia, they  form the apothecia, that first  image we saw, that's where the  spores are released. 

 Light can't get into the canopy  so we have a very nice cool, wet  environment.  Spores are released, they get  trapped, that's where infection  starts.  So most of our management is  trying to disrupt some of that  cycle accordingly.  From a grower's perspective,  they use many different factors  in their production of soybean  in the field.  Again, there's not necessarily  one that's better than the  other, although changes in plant  population is one that's on the  horizon that I think may help us  here in some of the management.  To illustrate here, these are  from the Wisconsin variety  trials.  Mortality here would be what  we'd clinically define as a dead  plant, so it doesn't produce  yield.  As you can see on the low end in  these trials we still had over  10% infection.  On the high end we were a little  higher.  We see this, these are nurseries  that are trying to facilitate  disease each year, but even when  you put conditions that are out  there, you oftentimes have very  low levels. 

 It's going to vary by what the  producer is growing in the  field.  What we try to provide the  producers is enough information  to help them make that  management decision.  This illustrates where they can  look at yield, to see what's a  good yielding soybean cultivar,  compared to the white mold  ratings, to make their best  decisions moving forward.  We also try to put the  information out.  I decided against showing the  video for a variety of reasons,  one, I think it would put us all  to sleep at the moment.  But we try to put from the  extension site information out  there.  Last year was a good year for  something like that where you  can go out in the field and  illustrate all the components  we're kind of talking about.  And again, yield's going to  vary.  So here we are talking about a  quantity.  No mycotoxin related issues, but  a physical quantity issue. 

 And since much of the soybean  crop in Wisconsin has food uses,  this is something that's always  of concern.  Management tries to alter your  cultural practices in the field.  Early planting date, narrow row  spacing, high seeding rate can  be risk factors for the  occurrence of white mold in the  field.  Fungicides, unless they're  biologically controlled, can be  effective, although it's much  like our wheat system.  Timing is critical.  So the cost-benefit is something  that's difficult to ascertain.  In terms of what a breeder or  what a grower's looking for,  resistance here is a very  different concept for putting it  out in the field.  You're often trying to alter the  architecture of the plant so  spores would be released when  the canopy hasn't closed.  So it's a little difficult to  come across.  And there were a lot of  questions that came up with new  varieties coming through from  the private sector that way. 

 There's no complete resistance,  very similar to our wheat  system.  So there isn't something we can  give a grower as a silver bullet  to go out there.  So kind of in summary for what I  wanted to present tonight a  little bit is, field crops in  Wisconsin are impacted by many  different diseases.  What I showed you today, if we  come back six months from now or  after the growing season, we'll  probably be talking about  something different.  These are ones that, when they  occur, are dramatic because  we're talking about issues  potentially of quantity, yield  loss, quality.  A couple of examples were  mycotoxins are a risk.  They can have direct or indirect  effects in our sort of food  source.  So what we see there in that  second point touches on that.  It's not always yield that we're  dealing with in these  situations.  What we advise growers to do  actually - So, the risk of any  disease in a given growing  season is something that's  difficult to predict. 

 We try to in some examples, we  can't always do it.  It's a function of many factors,  so what we advise the grower to  do is, know your field.  That sounds easy in theory, but  building that knowledge base  over time is something that can  be very difficult to do.  Building a database to keep tabs  on everything, just identifying  it in the field can be  difficult.  Best management practices often  integrate many different  approaches, and the one that we  haven't figured out how to  control is the weather, always.  And so most of the examples we  talked about tonight, the  environment had a large  component in that process.  When conditions come together,  we see the effects come out  accordingly.  So with that, I'd like to close  and I will open it up to any  questions that you may have.  Just some general  acknowledgements up there from  both my lab and some of our  cooperators.  If you're interested in what we  do on the plant pathology side  with field crops, there's some  links here that take you to some  of our general information and a  lot of the stuff that we talked  about tonight can be found there  as well. 

 So with that, I close and say  thank you.  (applause)