 Good morning everybody or I guess good afternoon. I'm in Washington DC right now so I'm not sure what time it is to be honest with today we're going to talk about tomato disease management. I'll probably focus more on disease that you might see in the home garden but we also see them in commercial fields. I've been in Auburn for 30 years. I'm an extension plant pathologist so I work with plant diseases, work with vegetables, tree fruits, small fruit, soybeans and corn and a few other crops so well versed. First I wanted to show you a slide of healthy looking tomatoes. This is what you're supposed to be growing. These are the last slide you'll see of healthy tomatoes during my talk. I'm always spending a lot of time looking at tomatoes that just don't look all that right. One more common diseases we see in the home garden is fusarium wilt. It's a soil-borne fungal disease, very common. It stays in the soil for long periods of time. We see it more in home gardens than we do in commercial fields because you have a lot of heirloom varieties being planted that don't have resistance to this pathogen. Oftentimes you'll see a yellowing on a few plants in the garden. It might be unilateral so maybe just half the plant is yellowing up but eventually after a week or two those plants will slowly wilt and die. If you were to cut open the stem at the soil line you'll see a brown discoloration in the vascular system. Basically the water conducting vessels just underneath the bark if you will but right at the soil line and heading into the crown. The soil-borne pathogen fusarium will invade the roots. It survives in the soil for many years. It has some resting spores. Once it gets inside to get water conducting vessels it'll block them up both the spores and mycelium which eventually causes the plant to wilt and die but it can't take a week or two for this to occur. You can see some examples of there in Foley and also more locally in Auburn. And the easiest way to identify it is you won't see any outer symptoms do say is the yellowing but sliced at stem open horizontally just above the soil line about six inches down into the crown and you'll see that brown discoloration stand out and that typically means of fusarium wilt. Sometimes we have a disease called verticillium wilt which I call its fusarium's Yankee cousin but I don't see that as often in Alabama as fusarium. Here's a variety trial and hopefully you could tell which variety was not resistant to fusarium but the best control is to use a fusarium wilt resistant cultivar. There are many of these on the market also plant and well-drained soils. You can use a crop rotation system to avoid infested areas but that's always a wise thing to do for many of your soil-borne diseases. You'd also use grafted plants say heirloom varieties on resistant rootstock which is becoming more popular and something like Andre DeSilver or our old Joe Kimble would be a good one to ask about that but the resistant varieties would be the best way to go most cost-effective for sure. Another will disease that we see is caused by a different type of biotic pathogen of bacterium and that's bacterial wilt and that's a soil-borne bacterial disease that invades the plants also through the roots also survives long periods of time in the soil. Usually we should see it though in very saturated soils very wet years we'll see this. It also plugs up the water vessels and you'll get a rapid wilting of the plan typically what this will go without the yellowing that we see with fusarium that oftentimes helps in field diagnosis. If you look inside the plant stem you'll see a discoloration much like I showed you with fusarium in the vascular system but oftentimes this will move into the center pit as you can see in the upper left hand corner. What we'll do in the lab Dr. Cassie Conner our diagnostician will do an ooze test bacterial ooze test one of my favorite things I've learned in plant pathology over many years but we'll take that wilt that discolored stem sticking in a glass of water give it about 30 seconds to a minute and if it's bacterial wilt you'll see this white milky strands of ooze streaming out of the brown area on that stem and that's a positive test for bacterial wilt and we probably do that about a dozen times in the lab at Auburn and every time we do it we were fascinated by it but that's a home testing for bacterial wilt. So the best control if you have a problem many times you see this in low lying areas and saturated soils you could plant susceptible crops in a I would only plant susceptible crops in infested areas maybe once every four years an area that has a history of it. Commercial growers can try soil fumigation home gardeners soil solidization to help eliminate the pathogen to some point. We do have new resistant varieties coming online such as BHN 6669 and Tropic Boy. These are just recent additions to our arsenal and you also could try grafted plants on resistant rootstock that's a basically a new technique over the last five years or so. Let's move into the foliar diseases which are I'll say more common but more easily recognized but the first one this is the first one I saw when I came to Alabama was early blight I was by the fungus and was alternatoria and often nice people will talk about their tomatoes firing up from the bottom I wasn't sure what they were talking about when I first got them. Got here but I realized it was early blight and it's a fungal disease that starts in the older leaves mature leaves at the base of the plant then moves up the plant firing it up causing those leaves to die that's not natural that's not a natural thing to do that's a pathogen and what we'll see is these target like lesions off to the right oftentimes surrounded by a yellow halo oftentimes you'll see it on tomato plants that are suffering from nitrogen deficiency as well so plants under stress. It's caused by a fungal pathogen that overwinners and plant debris in the soil so if you leave your tomato plants in the garden or in the field during the winter and if you had alternatoria last year or early blight last year you're going to have it again this year. You can also enter fields on air currents from a neighbor's yard or from down the road it begins on older leaves as a regular spots that then enlarge up to about a half inch in diameter they have that target like pattern concentric ring pattern and typically you will see a yellow halo surrounding these lesions and it's favored by warm weather and wet conditions so I think ideal temperatures are between 75 and 85 degrees free moisture either from rain or from old red irrigation will also push it along. You can go to the fruit and I typically I work with commercial growers and they're picking their fruit at the breaker stage when those tomatoes are just turning pink so you don't normally see the fruit rod stage but in home gardens more likely you're seeing this type of reaction where you have these concentric rings on the fruit themselves in the field you can get the foliation severe defoliation I'll show you a slide in a second which can't because you're eliminating the leaves in the photosynthetic area it'll reduce fruit size and fruit quality you can see sun scald in that fruit in the bottom right because the foliage is gone can't protect the fruit from the sun's rays and I've seen up to 50% yield reduction in commercial fields in the absence of a fungicide when the disease was at its full strength. We used to do a lot of fungicide trials up in the Coleman area back in the 90s on the left you can see somebody using bravo which is like diethane chlorophyll and no protective fungicide often times commercial growers will put on a protective fungicide once a week beginning three to seven days after transplanting and continuing up through harvest if they don't they'll run into what you see on the far right which is where there's no fungicide you can see early blights taken out about 85% of that foliage you'll get 45 50% yield reduction they're still putting on some fruit but they're not going to look all that good and you're not going to pick as many as you would like so under the right conditions what weather where this this and you notice this disease through scouting that is beginning to develop you need to get out of program to try and prevent its rapid development so as far as disease control look at your transplants I'll talk more about this with a couple other diseases but make sure you don't see any lesions that might indicate early blight or some of these other foliar diseases I'll talk about there are a few early blight resistant or tolerant varieties that are available some of these still might need to be treated with the fungicide and in severe cases or favorable weather conditions follow a follow a balanced fertility program avoid excessive overhead irrigation I would scout for a disease weekly if you're home guard or you're probably out there every day so take a peek down at the lower leaves and see what you're seeing if you see signs of early blight you might think about a fungicide spray program and again these might be about a seven day program seven to ten days program depending on the weather conditions hot and dry you could extend that program outwards warm and wet you might have to tighten it up to that seven day window and then remove disease tomato residue after harvest if you do have the disease problem you could bury it or just just put it in the garbage another disease that we sometimes see as target spot on tomato I do a lot of work with this disease on soybeans because it does have a very large host range but it also produces target like lesions that maybe not as dramatic as I see with early blight but similar pattern where it starts low in the plant and moves up it'll cause these brown to black lesions with a subtle concentric green pattern can be confused at early blight and it's possible that you get both diseases on the same plant so it can get quite confusing out in the field favored by high humidity and free moisture temperatures between 70 and 94 degrees will favor target spots a little little bit higher than we see with early blight very broad host range we have specialists working on with cotton I work with the same disease on soybeans but it does love tomatoes as well I think that's the same picture on the left but you can see those faint target like lesions on the left can also go to the fruit and be a problem so the longer you have those fruit in the field the more likely these diseases will go to the fruit obviously longer they're exposed with target spot you could rotate fields to avoid carryover residue from one year to the next you can just try to eliminate that residue just by burying it maybe maybe a hot compost pile would help eliminate volunteers and weeds especially those that are in the solar nations family the potato family like such as potatoes and peppers they can act as a reservoir source for this pathogen start with clean healthy transplants that you purchase at a center that you have had luck with in the past proper soil fertility avoid excessive over irrigation and then apply fungicides preventively when conditions favor disease development a lot of these foliar diseases if you wait for the disease to move halfway through the canopy before you spray you're just throwing away your money so you want to spray early when you first see it or when weather conditions favor it to try and get ahead of these problems bacterial spots is a significant problem I probably see more of this than just about anything and statewide and what you'll get is these little chocolate brown lesions on the leaves and sometimes you see it's just a slight yellow around it this is bacterial spot and it's often introduced on transplants you can't overwinter on residue but I think it's more coming in on transplants it attacks the leaves and the fruit favored by warm wet conditions as well you see a pattern there the leaf spots are a regular quite ragged and I'll show a picture of that as well and you also get fruit spots that can be raised scabby so it's not a pretty disease once the disease gets going on the left there are classic symptoms where you see somewhat of an angler type lesions to the bacterial spot lesions because the bacteria once it gets inside the leaf tissue it has a harder time crossing some of these major veins you can see these sharp angles to it with sometimes I use in the field to to help a little quick field diagnosis starts in the lower leaves moves up in the laboratory we also do an ooze test we can take that leaf on the left just cut a cut a slice open with a razor blade and stick it underneath the microscope and then those bacterias those thousands of cells will be oozing out of that brown tissue which is a just a quick and dirty method in the lab to confirm that you have bacterial spot same disease on peppers and bell peppers unfortunately with peppers we have resistant varieties available with tomatoes we do not at this point that I'm aware of oftentimes you'll see the lesions form more at the tip of the leaf as moisture moves the bacterial spores to the tips and they enter into the hydrothodes or some of the stomates but it's usually a bottom to top type progression on a plant and it also goes to the fruits you get these these scabby lesions on tomatoes somewhat sunken and as they progress they get pretty nasty looking crater like peppers oftentimes you'll see a bump on the fruit like a scabby like a little mini volcano but obviously that's not going to be very uh sellable on the marketplace or you're going to and I want to give those to your neighbors so bacterial spot best thing to do is avoid transplants and if you're buying your transplants from a nursery or a store just look for them closely this is one I bought in Montgomery about 20 years ago and it had you just see a couple brow lesions on that picture on the right and a couple leaves and that was I bought that plant that's how I spend my weekends at the garden centers looking for disease but that that I did a news test and it had bacterial spot and that whole tray at the store was infected with the disease so always examine your transplants before accepting delivery or buying them at the local market best way to control I think this disease other management tools disease-free transplants I mentioned avoid excessive overhead irrigation avoid working the gardener or a field when it's wet it's an easy way to move the bacterium and also knock off the microscopic leaf hairs it'll supply an opening for the bacterium to enter we often recommend copper mancosa which is a fungicide take-mix combinations as the two products together seem to help have a synergistic reaction to help reduce spot management but now we're starting to see copper resistant bacterial spot populations in the southeast they're pretty very common I'm doing some work with one of our bacteriologists and we're trying to figure out how much of our populations are resistant to copper and also if the pathogen maybe overwintering and weeds around the fields and if that's more common of an introduction than just transplants but possibly both but bacterial spots now tomato spotted will it's been around since about 1987 it's uh it's when we first identified an Alabama and this one is a virus disease so a different type of pathogen it's spread by thrips insects similar to aphids in a way what you'll see in the garden or in the field will be this severe stunting of the plants somewhat abnormal growth but the stunting usually gives it away most of your plants might look healthy and then you have one or two plants that look kind of ugly you'll get a terminal leaves will be distorted may turn a pale green the leaves you'll see a purple or browning to them I'll show you a slide of that as well you also can get ring spots on their fruit which kind of look kind of cool to a pathologist but not so much to a home gardener so you see bronzing on the foliage in the upper left some of that the little spot you see sometimes early in the season I have to kind of recalibrate myself each year because I think it looks like a bacterial spot but you'll see this more in the upper canopy than in the lower leaves but something not time to bronzing can be quite dramatic as you see in that one leaf and it can move down the petioles spread by western flower thrips which are you often in the blossoms they they they just inject the the virus during their feeding if you let the fruit ripen up and even if you don't you can't see these ring spots on their fruit which would be a sign of or a symptom of tomato spotted wilt virus this is a disease it also goes to peanuts so if you have peanut growers in here you're in the wire grass area there's a good chance that disease couldn't can't be moving back and forth between those crops people ask me if you can eat those fruit I would welcome to eat them if you like but they might not taste all that good because they're not ripping it up properly but you're not going to come down with ring spots on your face or hands but it is an interesting looking disease and fortunately over the last 10 years we've had a lot of spotted wilt resistant varieties come on to the marketplace some of these like Amelia are available bellow rose I see often some of the BHN varieties 602 and 640 you can't find at your local stores some of these others that are listed maybe off the market I think mountain glory just have come out recently so look for resistant varieties look for the tags do some research on it there are a couple roma types that have resistance as well if you're into that type of tomato I also mentioned reflective mulches may reduce thrift feeding and effective weed control in and around the field may help reduce overwintering inoculum but that's a little bit far to go of just if you have this disease every year go with a resistant variety and that's much better to trying to spray and insecticide or using some of these cultural practices let's buy the wilt on the left on tomatoes fancy ring spots in the center this is how we with test for the lab on the right is dr. Joe Kimball one of our our old regional extension agents we were evaluating looking for bacterial spot different diseases in some of these transplant houses and oftentimes the disease these diseases can come in and oftentimes lc spotted wilt coming in on peppers later in the season so always be aware of the diseases when you're picking up transplants nice way to avoid them this is a disease southern blight that I think I probably see a more commercial field than I do in backyard garden which is a good thing for home gardeners major problem on a lot of crops it's called southern blight another soil borne fungal disease that causes that white fungal growth on the stem or any basically any part plant part that touching the soil soil borne tax over 1200 crops and weeds vegetable wise tomatoes peppers eggplant snap beans are all susceptible to it as well as all your curbits I often see this on watermelon and cantaloupe or pumpkin fruit that are touching the soil where this pathogen is present so any organic matter that touches moist and fasted soil this pathogen can take off and attack that that plant part what you'll see is typically this white fungal growth at the base of the plant near the stem line and what I'll see in commercial fields is that the disease will move down a row so it doesn't usually well it doesn't usually take out a whole field it might take out a whole small garden but you'll see the disease moving from one plant to the next maybe through irrigation water this is on raised beds in a commercial field up on sand mountain but you'll see it move from plant to plant so sometimes you could when you first see a plant wilting and the plants are used this usually starts to show up this is the plants are starting to put on fruit you could remove that plant with the soil around its base and possibly slow the disease down but if not it'll just continue to move from plant to plant the cross row spread is not as common so you get a rapid wilting of the plants and then you get a crown rod you get a black canker or discoloration at the stem line looks like it's been girdled then the white mole under moist conditions will cover up that point at the at the soil line eventually you'll get these small round sclerotia which form into mycelium and those sclerotia are just little seed-like structures that is dormant mycelium of the fungus and these could be white to orange tan to reddish brown to dark brown and that's dormant mycelium and it could survive in yourself for six seven eight years in the absence of a host so once you get this disease you're you're kind of in a you're in a spot it's not a good spot to be in so I mentioned anything touching the ground so if you have a foliar disease like early blight or anything that knocks the leaves off once those leaves hit the ground it could stimulate the fungus in the soil to become active you can see it on the peppers on the left that we had a problem with bacterial spot in that field and southern blight started attacking the fruit they were touching the ground cantaloupe on the right are just melting away due to southern blight on the right on infested moist soil so getting those plants up maybe putting down in good mulch or plastic would help reduce the problem you'll want to avoid low pH situations what seems to help stimulate the disease rotate crops but it does have a very wide host range plant early before the summer heat sets in because it does sort of like the the heat of alabama so early plantings might do better than late in infested fields improve air circulation good spacing between plants might be of some benefit you can try to remove symptomatic plants quickly plus the soil around the base to try and reduce it heart mentalize it basically from from spreading down that row I don't like recommending deep tillage but you can do this in certain situations to try and bury those chlorosia deeper than six inches deep in the soil that fungus has a hard time moving back up to the soil surface so you may reduce the amount of noxious going into the following year if you're planting tomatoes or peppers continuously commercial growers can fumigate with a product like t-loan c-35 or pick chlor to help reduce the problem home gardeners you're more you might try soil solarization if you have a severe problem try this in the garden if you and we have a nice normal hot summer in alabama with a lot of solarizing days that might reduce the amount of southern blight you have in that area we're going to finish up with nematodes microscopic aroundworms most numerous animal in the face of the earth more numerous than insects just not as diverse but about 10 percent of nematodes are plant parasites that live in the soil and feed on the roots of plants and we have about 10 or 12 different damaging species in alabama they feed with a stylet which is you can see on the left that's sort of that's like a hyperdermic needle they have muscles attached to the basal bulb of that stylet that allow the nematode to puncture root cells and then they secrete enzymes that move into the cell liquefied basically and then they reverse the flow and suck that out and that's how they gain their nutrition and damage the plants and you can find hundreds of nematodes in the soil some good some bad some are feeder on bacteria some are feeding on fungi there is a whole different world underneath the soil for sure when you're when you're mostly concerned with with tomatoes is root not nematode it produces these large galls on the roots it's not because you have a nematode the size of your thumb and nerve size of a necklace because you have multiple nematodes attacking that that root they're secreting enzymes in that case that increase the size of the cells around their head of the plant increase the size of the cells of the plant at the host and that's where they get as they set up their feeding side you might have multiple you have multiple nematodes saying this infected infected plant so here's you can see an adult female in the upper left hand corner they start off verma form or worm like snake like but rooting out it will swell up into this bulbous form this is adult female that large blob on top that looks like a dark cloud that's about 10 percent of their 258 she produces in one generation that are hatched immediately little juvenile nematodes swim off and attack other parts of the root or other plants those are just stained red so you can see them but right around her head region which is that pointy area on the bottom left is where she'll secret enzymes and then the cells around that head area increase in size and number and that gives you those large gall roots in the bottom left and you have a root system like that it's not functioning properly you're not going to take up moisture and nutrients so you see plants wilting when they really shouldn't be and you might see signs like nitrogen efficiency where the lower leaves are yellowing like you see on the slide on the right so plant social nitrogen efficiency I'm sorry yellowing nutrient problems and occasionally you'll see a plant die outright um but you'll see that stunting and you might not see this right away it's not a it's a disease you call it the hidden enemy because you don't see the nematodes but you do see the symptoms with what you can think well that's probably a nitrogen efficiency or drought so every so often dig up a few plants if you see this and just look for these galls which are pretty easy to detect and nothing else is going to cause that on your tomatoes as far as management first thing you want to do if you're moving into a new home or a new field or a new garden area take a semit soil sample and have it inspected for nematodes you probably want to do this in the best to do it in the fall because that's one of the populations they're a highest nematode populations drop dramatically over the winter time especially a cold winter so you want to sample in the fall that's best and get about a pint of soil from your garden area from different spots so you see what the population looks like if you do have nematodes you might want to choose a different area to go to the plant if you had a history of nematodes or if you do have and you definitely want to go with a root not resistant variety typically these have n on the label with the stands for for on root not nematode resistance can reduce plant stress to the use of organic matters good compost sometimes by doing this you're adding antagonists both fungi bacteria other nematodes that might attack that that that pathogen sanitation at the end of the year if you have root not nematodes you can dig those plants up i just leave the root system on the soil surface and let the sun be down on it that will burn up the population to some extent you can't rotate root now though has a very as i think it goes over 3000 different holes so it's rotation is a kind of a tough order there suppressive crops we do have a handout nematodes suppressive crops and things like sesame seed crotal area partridge p certain marigold varieties that you can plant in a nematode infested area and they give off chemicals that will kill these nematodes or inhibit their reproduction and that's that's an option when you're you have limited land space or limited garden space but there is a handout on the aces website and then solarization is also a nice method to try and reduce populations but even with that if everything works out perfectly those nematodes are eventually going to move back into that area soil is moved around but it is a way to knock populations down when you're when you have limited area to grow i put this up i think i use this lasher this is a friend of mine dr rebecca melanson from mississippi state she has a very nice publication common diseases of tomatoes i would recommend googling that publication on the mississippi state website common diseases of tomatoes we're revising ours and uh but rebecca has done a nice job with that and it gives you some very helpful information also talks about some of the fungicide that you might be spending time with okay and with that i'll stop again i'm edsacor extension plant pathologist you could send me an email if you like here's my cell phone number and if you really want to learn things follow me on twitter at alabama and i i post something just about every day and my concern soy beans one day tomatoes the next trees and so on but i i try and be informative when i'm doing this and uh if you follow me i think you'll learn a lot