Favorite Sermon Add to Playlist
Logo of 2019 Adventist Agricultural Association Conference: True Success

Plant Pathology - Part 3

Michael Trevizo


Farmer, Agricultural Reformer, Production Manager at Five College Farms, & Soil Scientist with a focus on Soil Science and Agronomy; Education: Bacherlor of Science in Crop and Soil Science, Oregon State University.


  • January 15, 2019
    8:00 AM
Logo of Creative Commons BY-NC-ND 3.0 (US)

Copyright ©2019 AudioVerse.

Free sharing permitted under the Creative Commons BY-NC-ND 3.0 (US) license.

The ideas in this recording are those of its contributors and may not necessarily reflect the views of AudioVerse.


Audio Downloads

This transcript may be automatically generated

Timeline of infection is a really important thing however in this timeline we don't actually put you know time as we understand it say a day or a week or a month etc Some diseases are very slow so you know that takes a couple of years before you really see it while other things are fast they can be a couple of days so the amount of time in between these is varies from disease to disease but the important thing is to understand the different steps that these pathogens go through to get into your crop and actually affected so for from the pathogens and it's not that much different for bacterial pathogens Well actually it is bacteria and viruses they're kind of in a different category I'll talk a little bit about bacteria and viruses later but for fungus we have a pretty infection stage which is your germination in other words that's the point where that fungal spores germinated All right so I remember I got you guys all the way up to the point before we're on the leaf OK now we're on the leaf what's going on now well that's poor have germinated it's decided that your apple tree is just sick as a dog and it wants to attack it and consume it why because in my opinion God designed it to do so you know if you have Darwin he'll tell you on the strong survive but what I mean different points of view but at the end of the day it's serving the same purpose so that Spore germinates starts to grow All right so on the host now next step it produces a germ Tube Remember that video that germ Tube started coming out that's starting the search it's looking for a good place to drop anchor and in fact when it finds a good place where it wants to be then the Apress already I'm sorry in this form which is around around almost peg that will begin to actually penetrate through the cells. So that right there these are 2 things and this particular portion right here you have really you have 3 things that are critical one there are actually different ways like. I Just how do I say this and a lot of research has gone into trying to figure out what is actually signaling to pathogens hey you know I'm a healthy plant and the other one says No I'm sick one except what what are these signals so there's a lot of enzymes and other things that I'm not even going to go there but anyhow so either the absence of one or the presence of one signals to the pathogen this is a good place to establish and build a home you know think of the frontiers of the Oregon Trail if you will coming out here they went through what 2000 miles of desert before they finally started to see pine trees and they said let's settle here in Oregon Well it's kind of the same thing it's gone through all sorts of different areas all the sudden it gets to this host and says wow this is what I've been looking for all my life that's let's establish here so what's going on there is usually associated with plant health so to avoid that crucial step again you go back to soil health. Or sometimes it's age of the crop is really old in the starts to get hit really old vineyards old orchards I know they started to pull out a lot of the old Then years in the southern Willamette Valley that were planted in the sixty's and fifty's and forty's when they 1st started to bring the vines into Oregon because they discovered that they were just susceptible to certain diseases so they start ripping amount now they're put new varieties in. Filbert they're ripping out filberts everywhere and they figured out how to get genetic resistance just only partial genetic resistance to Filbert light so now they're putting up filberts everywhere everywhere you look out here you see these silver trees are they can't go anywhere but you know it only has partial genetic resistance in 20 years or supposedly they're going to be attacked just like the ones that are there now but now. That's the host and then you have the germ Tube search so that germ Tube stretches out and it depends on what it is because every fungus is different every host is different but they have actually discovered that the fungus has the ability to actually sense changes in the graphy of the leaf Now I know that seems strange but when you're a fungus on a spore I mean when you're spore for a fungus on a leaf you know the lead could be as to use like the Parking Lot of a football stadium it's huge so you can really sense changes in the Potter for you right because it's just scale So these changes in topography is what dictate you know do I want to make an a priori I'm writing this tomatoes or you know maybe I want to go right between these 2 selves over here where the 3rd or pressure is not right because maybe your minerals are out of balance or maybe your moisture isn't right maybe you've drought stressed your crop too much or added too much water etc That's what it's looking for than Then it starts to set a penetration peg that penetration peg is what actually at this point you will if you will you. It starts to actually penetrate the leaf and look for a place to form a hostage or am where you know it starts to actually release toxins into the cell and it starts to actually take nutrients out of the plan or out of the host and begins to suppress to the host system of defenses which is actually just like the plant immune system and then it begins to enter into a reproductive stage so different path and different most fungal sprays you get whether it's organic or conventional The only thing they're good for is affecting it somewhere over here where were these are and they vary but they're here so by the time you have a serious infection most of those sprays are useless. It's too late. You need to either make your applications post. Germination or you're probably not going to be successful and that's if you're taking that approach now Wilton top more or I'll talk tomorrow more about plant health but that's that's for that now so let's see getting inside the plant so it's very important for the fungal spore which is right there and you see the. Comes down through and it's splitting into being between the different cells so what is in between those cells the mortar if you will if you if you understand building brick walls you know the cement that goes in between the bricks is mortar that holds those bricks together make set brick wall strong well the mortar in yourselves not only the cells in your body but the cells in your plant it's calcium and silica if it's not in the ground going to be there either it's like trying to build a brick wall with no mortar cut have it in the ground folks so it's not there that fungus will come in and say hey this is easy street and just spread out get between all those cells and start you know doing whatever it's going to do but not all of them are that way some of them come into this tomatoes or they come in through wounds you know this tomato is where. Transpiration goes through but what's interesting to note is those changes in topographies on that leaf you realise it's it's I don't even know you probably measure it in angstroms it's so small it's very very small but it's a different change so again if you don't have the right potassium in your soil and the right sodium in your soil you're not going to have it in your crop if you don't have that right sodium and potassium ratios in those tomato cells the pressure may not be the same the it may be swollen it may be shrunken and the crops as a you know I can get into this tomato even when it's close very easily so proper health again goes into that as well then you have to do. Which are actually I think this is with the fern if I remember which is similar to the models. And then it can also go through wounds so any damage that is done with plants leaves or are opened or could be any type of mechanical damage you can enter through there as well. And now here's a more colorful image of the direct attack by a fungal pathogen so this is essentially is a germ. Spore the has germinated and as soon as it germinates these these guys right here these are enzymes that are released nations that are released by the fungal organism essentially it's like a tool box if you will every single fungal Spore has this tool box of these enzymes are like tools that it can release into the immediate environment to break down the waxy cuticles which is the wax on the surface of your plant leaf and then once it breaks that down it starts to actually form that sore him in that penetration peg so the 1st step it needs to do is like you saw the videos get through that waxy cuticle So what does it need it need certain in dimes so these were executables again one of the most important things there's copper and zinc those those things are those other minerals are deficient you don't get the the same strength that you're looking for and then of course once you pass that you get into the. Right in between the cell the cell walls right here which again those cell walls are produced or are strengthen with. Calcium it see this is this came out kind of. OK So this actually is this on the top is the break out of the waxy cuticle So what you have on top is a wax layer than the wax and then the cute in the cellulose Lamela the pectin Lamell of the cellulose layer the plasma membrane and then the side of Plasm So it has to get through all of that before it finally gets down to the cell to form a story how do you how does it do that you know 1st 1st off how does a plant develop healthy cuticles proper use. And you know what's funny folks is that this right here that you see if you've got athlete's foot it's no different if you've got different other funguses in your bodies and your nails etc It's no different it's the same when it attacks your body as one of the tax plan so again. This is the same picture as before wouldn't skip through that so again well I thought I'd put this in here already we went over this incubation period late in period in question period. All right so fungal infection so here's a microscopic view a look I think this is electron microscope. So there's your fungal spore there's very percent which is you see it right here and in a black and white it comes through and starts these little circles that you see right there are hostile that's actually going into the cell and it's looking to hijack the cell and get the cell to work for it it's kind of a way of coming in the back door if you will and I really want to make a point though when I took 5 at the holiday for the 1st time on oh is that a secular university you know. Just yeah it was a secular Univer hour even though yeah it was a secular university all kinds of craziness in there I'll sit in the chair kind of like you guys was a classroom of a couple 100 students and stuff professor was going off talking about everything I'm talking about and I fell I seriously felt it was preaching to me because every time that man described these diseases and how they infiltrated the plant it reminds it really I could see the parallels with how Satan infiltrates the church and I see how he infiltrate your home and how he breaks it down and how he gets behind these layers you know the 1st layer should be what the husband how do you do that get him out a way. Out of the home he had a home he'll get in there and then what does he do. Divide and conquer get everybody to start fighting against each other. And then start getting them to start feeding him somehow whether it be through bad habits or what have you and I just I just see it in you know when you're sitting there think about that think of those parallels because I see it very much in the church and I see it in our homes and in the same way that he. Tells us that Satan is the one that created these pathogens how exactly I don't imagine he came down here and actually I don't know but that's the wisdom that we're given I don't want to make assumptions outside of what we're being told but here again is another image this one is going into this tomato these are the cells that actually expanding contract to control transpiration in your plant and to bring new tree bring moisture through the vascular system and sometimes we have some that come in through their cell in this particular case looking at being rust pathogen forms and they pursue him directly over the model thereby reducing the need for numerous informatic tools so it doesn't even need that it just comes right in the open door. This is again I think this is being rushed Now this is a similar thing where you have like I was saying the changes in that the pod are free so you know they're trying to breed for genetic resistance to stem or us they want to make they want to find a way to grow a leaf tissue that's straight flat so you won't have the infection like that which is you know I don't know I laugh because they put in so much energy and so much effort into genetically engineering and somehow coming up with these genetics where they can overcome these tricks and a lot of times are really successful at doing that however I mean some of this is just it goes back to nutrition get the nutrition right and soil you have figured out now. It's callee loss' this is if you're into the organic chemistry that's what it looks like there. Is is something that the plant puts out to form a pill which is essentially it tries to. One of the plant's. Responses to fungal attacks is to try to build a wall or a barrier and this is what it uses but if the pathogen has the ability to break that down that it will break it down and get through so it's almost like a cat and mouse game when we start talking about genetic resistance and and different host defenses as well as some of the fences Here's an example of the propeller So in this particular case he had a fungal spores that everything's perfect to put out the broke down through the cuticles the host sense that the fungus was coming in develop the can. The fungus did not have the capacity to break that down the host one in other words you have resistance so you see you have to ask yourself this is at the cellular level in other words this means an expression of D.N.A. an expression of genetic information or get into translation and transcription etc later but this is expression of genetic information if you do not have the simple building blocks to express that genetic information in other words the raw materials in other words plant you tradition that how you going to do this you're not pathogen wins there's a possibility of your crops to lose. It's simple folks you know is that complicated. If a person is like wrong but then it's like wow yeah so then if the Develop a hostile area this is what it looks like it hijacks the cell it takes control of the rival zones it gets it to work for itself it wants to express certain things and starts producing sending nutrients off to the rest of the fungus reproducing producing more spores in the surface here that launch out like you saw in the video producing more disease somewhere else it's a cat and mouse game it really is a cat and mouse game just at a cellular level involving a lot of very complicated things that a lot of the scientific community still hasn't quite wrap their head around. So here's some more pictures here's a hospital room so there you have the membrane again to get through that membrane What do you need you need a fossil lip and by layer if you're deficient in phosphorus guess what you're not going to produce a fossil lifted by layer you need phosphorus so phosphorous deficient plants are usually going to get hit hard fungus so hostile Oriel plasma membrane is formed and here you have the nuclei of the Act cruel and what am I looking at here I think that's the actual fungus and then sometimes the host plasma membrane wraps right around the house door E M And then you have nutrient exchanges between the fungus and the cell so essentially the fungus is stealing or robbing everything the cell has to offer here's a stem blight I believe that what I'm looking at affected you know types of those are more commonly bacterial toxins post Pacific Necker trophic fungus attack with toxins. In this particular case when Remember I talked about facultative except for a versus. Other different types of trophic means just I think some of the guys in the central figure that just means that in other words what what's it looking for how what it consumes would be a good way like how does it survive what energy does it consume in our in our case we're talking Metro which has come from necromancer I think it's a root word which is essentially saying dead it feeds fungus that feeds on dead plant tissues fungus that's what that is so when those funguses attack your plant they're actually releasing toxins and one of the ways that your plant can defend itself part of its immune system again is expression of its genetic code is to produce. Proteins that will neutralize those toxins and if it can neutralize those toxins it can stop the host fungus from killing those plants cells and then feeding on the dead tissues it's again simple yet very complicated. And of course most of these funguses that are nectar trophic are very hostess ific like stumbling very very specific they can't go and affect some other thing it's usually only a particular variety of wheat or a particular variety of you know grasses maybe corn except they're very very very host Pacific all pathogen groups make affected so again those those those toxins of things that are sent out are referred to as affected so here you have the nucleus and then you have the bacterial organism it comes in it's the bacteria again will excrete different types of the factors doing similar to the fungus it wants to break it down set it down in here and it wants to somehow either break down the cell walls or break down the cells and somehow get the cell to work for the bacterium if the bacteria or the host has a resistance genetic resistance to it whether it be genetic or it has a nutrients it needs to express that genetics it will neutralize those toxins those effectives that are sent out by bacteria or by the fungus here that has formed a hospital room or in this case we're looking at a chloroplast where I'm sorry we're looking at a cell that has been attacked by name a toad. And it's all the same thing limited scent of factors everything put it factors into plants anything that touches it will put some sort of protein into there where the plant can sense if it cannot sense or it does not put of its system of defenses it won't go into a defense mode and that takes energy so plants do not go into defense mode like we don't push our immune system because it takes a lot of energy so we're doing a lot of hydrotherapy it demands a lot from your system because if you're building you're increasing your white blood cell count you're actually trying to push your immune system to fight things you're mimicking infection when you 200 therapy in plants they call it priming it where you come in and you throw in some effectors in there and you prime the whole plant to make it make it think that it's been attacked by some sort of pathogen and then the whole system if it is systemic the fence the whole plant will actually start producing it but it takes energy so that means that it's not going to be as productive as it used to be yields are going to go down a little bit. I went over this as well so you see the same thing so I talked about again the fences so when you get to this point where the penetration peg you know you have a propeller formation if the propeller formation was not effective at stopping the plant then you have a hostelry in forming and then you have talks information trophic. Funguses or you have a story information and bio trophic funguses but at that point you have your basal system of defenses which again is other effectors that are released by the plants proteins etc destroyed to try to neutralize this and then you have a suppression of host defenses is what will become from that it will essentially try to overcome that if the plant has the capacity to sense this but doesn't have any way to protect itself it goes through what is referred to as hypersensitive hyper sensitive response or hyper sensitivity or programmed cell death essentially the plant the cells kill themselves if it doesn't have a way to defend itself it kills itself what does that sound life. Yeah what does else as a sound like. Remember folks sin is a disease if there is no cure to that disease what is the host that kills itself yes the gospel right there. If if if the head being Christ has no way to defend itself against the disease that the body has which is sin what does it do it kills itself. And it's right there I couldn't believe it when I saw it myself I'll show you pictures later I don't think I have one but anyway they kill themselves and get these white spots on the leaf tissues Not only does it kill itself but it sends a signal to the neighbors and they kill themselves too they say die for being under attack don't let them take our nutrition and it sacrifices itself to save the rest of the plant interested in it and or if it doesn't do that then it releases federal elections which will activate the systemic acquired resistance which is a form of resistance is like saying here comes a certain pathogen that releases a certain. Election which will go out throughout the entire system of the plant and the whole plant and sometimes even the neighboring plants will put up their defenses against that pathogen so it's pretty complex you know and all this happened by chance you guys go figure it out anyway. G M O's genetically engineer. Or crop crop systems have entered the food production system global It has allowed us to feed the world whether we like it or not you can argue that point. That's a fact it's a historical fact not necessarily a scientific one but yes it does have some science to it however is it necessarily a bad thing now my answer to that question is I have multiple different answers 1st off from my understanding of the science I have not yet been able to put together where. A cell with a nucleus that has some sort of Jeanette genes brought into it that are other than the genes that were here is somehow negatively affecting a human being I have read studies that they have brought up but I don't really see the science and now my problem personally is not a most them selves My problem is the type of farming that G.M.O. foods allow us to do and have pushed the world into doing because you can grow dim genetically engineer corn even go out there and you can put your BT corner BT roundup BT Roundup Ready corn that allows you to spray things like round it allows you to it allows the host we go back actually that's a good point rather than your brother's a BT corn what is BT corn What is B T What is bacillus their inventions besides a fancy scientific name there's a particular genes that they took from the bacterium bacillus learned Gensis that they transferred located into the corn genome that now the corn can produce and so now the corn is producing those eggs dates which allow it to which prohibit any type of. Coleoptera which is just a fancy word for caterpillars from actually feeding on that corn but now it's expressing genes that God didn't design corn to express and that's one of my big concerns but that's just only to BT corn now I can't make that concern with Bt cotton why because I don't eat cotton I wear cotton but can it affect me by having contact with me I honestly I don't know I really don't know I can't answer that question on a professional level because I don't have an answer for that question but with the Roundup Ready stuff I can because what round up what life is a does is that lots of nutrients in the soil making them unavailable to plants thus killing the plants. And what we're growing is a large amount of food you know a whole lot of bang with very little buck and it doesn't have the nutrition we need and that's what I believe is a large driver of disease in this world today is is that. The absence of those those nutrients which is more than just the basic building blocks of carbon hydrogen oxygen nitrogen potassium phosphorus and maybe a few calcium in a couple other things a build just the corn stock in the corn. Brothers talking about sort of Caylee which is a cross bred between. Barley and we Right right right and we I'm sorry Ryan we so that allows folks to grow or farmers to grow this grain in a colder climate. I guess I can't say that that would be an issue unless they're bringing in some other type of genes but what I what I 1st up that takes me into a whole other argument 1st of all. Satan is very clever so what Satan has done is that he has taken all type of breeding whether it involved transgenic that is bringing genes in from maybe taking a gene out of a pig and put it into a tomato or a bacterium and putting it into a corn etc But you're it's horizontal breeding where you're moving genes that way with things that normally don't breed and the actual genetic breeding of crossbreeding plants like what you're talking about and bungled it all under the term genetic engineering. So now scientifically speaking genetic engineering G.M.O. scientifically is a word that has no meaning. It's just a word that's popular throughout you know normal circles it doesn't have a scientific mean in science it's genetic engineering or it's more specific you know Chris for eccentric cetera they use scientific term the Knology but they bungled all that breeding into genetic engineering so like what you're talking about it's not a horizontal shift where you're bringing genes in from some foreign thing that has no business being in there trying to play God to break something else to solve a problem when really the problem from the very beginning was the production system and the economics and political issues that are driving farm in agriculture in our country especially in developed countries it's not so much you know yields and many other issues but anyhow that takes us down another path I don't really want to go to so what you're talking about with that particular plant I have no problem with however with introducing selves to whatever means that is whether it's Chris for what have you it's I don't I don't really feel comfortable with that because of what I said the agricultural practices that are brings in but you have to understand that not genetically engineering Nowadays the way is scientifically that's fine does not necessarily mean that you're dealing with organisms like that so the statement was you know he's looking at it from a moral is that when he said I'm sorry for the Sophocles philosophical standpoint Well if we do this with plants we can do it with humans and we're already doing it I believe with cows and sheep and I don't remember what else but yeah you make a good point you know what I'm referring to my statement earlier I want to reiterate is not about moral Lee or philosophically it's simply from a scientific standpoint I don't see that argue from a religious standpoint I have a very serious concern because I don't like the idea of putting things into my body that God didn't design. I don't like the idea of somebody playing God for me and then telling me that they're not going to tell me that they played God. You know the whole thing reeks with really Satan's practices. So can I come over here and show you some scientific article that says Oh if you use is G.M.O. you're going to die of whatever you know no I can't do that but you know I also can come over here and show you a scientific journal that says the 7 days to 7 but I don't really need it I have the Bible and the word of the Lord so when I make my own decisions for my own diet I decide I don't want to consume those things because of the saith the Lord not the faith of man all pathogen groups make a sectors you know bacteria fungus the methodes a physics extra Anyway the effect there is are certain proteins and things that are released by the. Pathogen in order to break into the host and try to. Get into the host and in fact host so there are. If they have there are in some instances manufactured synthetic forms of these defectors which they what they call prime the plant with them I believe they do some of this in some of the vineyards. A lot of this is usually done in to chew tissue culture and I'm going to be honest with the I don't I've never done it and I don't know I only know about it. So is it really necessary I know for one it's very expensive but the thing is you know again piggybacking on what what's his name what Mark just said when it comes to producing or shall we say manufacturing food in this country United States and all the developed countries very very little profit to be made but when you're going to grow it to refer to the ultimately make some sort of intoxicating substance. A lot of money isn't it so in the vineyard industry millions of dollars are in that and hot I was lucky and I couldn't believe a job offer for $170000.00 of legal hops to make beer you know kind of this is going nuts I got people asking to go grow cannabis I don't want to grow cannabis. I want to find a job growing food you know and and that's out kind of how I ended up leaving or going to going to live Massachusetts I don't want to Massachusetts I don't like doing I lucked out fine and happy right here I can find a job growing food I could only find jobs growing intoxicating substances like hops or cannabis or wine now what interested in those things so. Going back to what you're asking is that those type of expensive measures are usually only taken with expensive crops and those are usually intoxicating crops like tobacco or cannabis or wine or hops or whatever barley is another one but barley is NOT use only for beer making me they do other things with it too. But apple canker most of those cancers are bacterium does that cereal disease is. The most important thing with all your bacteria is there and and well not just bacteria but fungus same with fire blight the biggest problem actually we're just talking with. Alan here a lot of the some of the study that was done out of the O.S.U. is looking at fertilizing when you fertilize and how certain levels of nutrients can block out other levels of nutrients so one of the big things with fire blight. And I believe it may even be with apple canker is when you apply or nitrogen fertilizer Zz and how they may affect the uptake of other nutrients with orchards unlike most of your other perennial I'm sorry. Annual cross with perennials unlike your annual Zz they don't just take up nutrients nonstop all the time. Anything they look for certain nutrients at certain times when you're fertilizing and your fertilizing in excessive amounts at the wrong time you have to see the block nutrients one of the most desired an example is excess of nitrogen fertilization on orchards in the spring in the spring when you are supposed to be Flora forming your floral buds which are going to become ultimately your apples if you put too much nitrogen down it has a tendency to block calcium when it blocks that calcium even though it may be readily available in the soil that ultimately will result in a lot of fire blight and in different Apple scabs and other diseases that are associated with fungus is on the fruit simply because you weakened the plant the fruit tissues so the epidermal cells which is the exterior of your apple. Is essentially a protective layer of not only the seeds but the edible portion that's inside if you want to harvest and take a good harvest and put it in storage and keep it there like apples for like a year or whatever it's going to be and you do not have strong plant tissues. Then it's not going to keep in store for long so what happened was studies that they looked at is when they apply the nitrogen fertilizers and how much and what the what effects they have and what they saw was that excess of nitrogen fertilizer tend to affect the transportation of calcium particularly but other nutrients in the spring which affect the quality of the floral buds which ultimately affect the quality of the fruit because it's the only time of the year where those tissues are actually formed you get into a little bit of plant biology but. Once that once that Will it see it's at the time it's the same with tomatoes you get blossom and rot not because you've deficient in blossom in calcium when that fruit is swelling you were deficient in calcium at the point where the floral Bud was being formed. And that's when that nutrient goes in there if it's not available at that time then blossom in RAW if it's available at that time you know blossom into apples are very similar if it's available at that time you won't have to fight with them so much is the same with peaches another stone fruits fired light takes off as well fire but being a bacterium looks for those rich simple sugars oftentimes brought about by high nitrogen so too much nitrogen on the ground you're feeding the fire like too much sugar you feed the wrong bacteria. The wrong fungus in the wrong. Thing and very much of a relief this media was brought to you by audio to a website dedicated to spreading God's word through free sermon audio and much more if you would like to know more about audio version or if you'd like to listen to more sermon leave the W.W.W. audio verse or.


Embed Code

Short URL