Sclerotinia sclerotiorum
Referred to as tone bunkum , bloodless mold , or sclerotinia stem rot , this disease can play mayhem on tomato plants in cold , pixilated climates , and may persist in the soil for up to 10 years .
And it ’s not only your tomatoes that may be at jeopardy . lily-white mold can infect more than 400 metal money of plant life , including such important crops aspotatoesandpeppers .
because of the fungous pathogenSclerotinia sclerotiorum , this disease is widespread in sub - tropical and temperate area . Over 60 nameshave been used to date to mention to disease triggered by this pathogen .
Photo by Rebecca A. Melanson, Bugwood.org.CC BY-NC.
Not surprisingly , it can also infect a gravid number of weeds , which can wait on to maintain a reservoir of the pathogen .
Weed host let in lamb’s - quarter , pigweed , Canada thistle , wild leaf mustard , hairy nightshade , and ragweed – a who ’s who of prominent weeds .
Here ’s what I will cover :
Photo by Rebecca A. Melanson, Bugwood.org.CC BY-NC.
What You’ll Learn
Sclerotinia Stem Rot Symptoms
A classic symptom of this disease is the production of structures calledsclerotiathat give the being its scientific name . These selection anatomical structure look like rat droppings – small , calamitous , hard , cylindric objective .
The sclerotia form in or on dead industrial plant tissue . you may find them inside tomato tissue that has turned whitened and dry due to the disease . This symptom in tomato plant gives the disease its alternative name , tone rot .
The first sign of transmission by this pathogen is at the root word of the main stem at the stain line or on blue branches . At first , the disease manifests as washy soft rots and bleached area on the leaf axils and stems .
Next , a bloodless bleary mould grows both inside and outside the plant . It then spread to the flowers , leafstalk , leaf , and stem . The yield can also be infected , turn gray , and rot .
As the disease go on , the plant will wilt . The tissue become even more dyed and brittle , and in seven to 10 day , the black sclerotia are formed . If you cut the sclerotia subject , their inside are pink - white .
Favorable Weather for Infection
lily-white mold is a disease of nerveless , wet atmospheric condition – temperatures from 59 to 70 ° F . Nighttime temperature around 60 ° F are particularly golden for infection .
Spores are most likely to infect tomato plants after 16 - 72 hours of continuous wetness with a relative humidity that is slap-up than 90 pct .
The plants are most susceptible when they are bloom , so give special care to the flowers if the weather is cool and wet .
The Disease Cycle
If the environment is quick and juiceless , the genus Sclerotium can remain in the dirt for year – as infectious as ever .
Once conditions are nerveless and favorable for the fungus , the Sclerotium within the top in or two of soil germinate and give rise fruiting bodies . You may be capable to see these – they look like piddling mushrooms on the surface of the soil .
The fruiting bodies produce spore right above the soil argumentation that are very sticky . These can survive on a leaf for up to two weeks under lucky conditions .
The spore typically germinate on susceptible tissue paper such as dead heyday . This is often the case in leafage axil where a prime blossom has fall and become stuck .
Once the pathogen has become establish in dilapidate tissue paper , it be active on to aggress the good for you parts of plant .
The only good thing about this disease is that once it has completed its disease hertz , it will not develop spores until the next class when favorable conditions return .
However , you are stuck with those genus Sclerotium in the soil – a harbinger of end of the world for your tomato plants .
How Your Garden Can Become Infested with Timber Rot
The most common fashion that timber putrefaction is distribute is by spores that flub through the air from septic crops or weeds , and land on your unfortunate plants .
If successful , the fungus will then produce Sclerotium , which can spread the disease further in your garden .
The wind can also blow soil or crop junk overrun with sclerotia into your garden .
Water can spread spores or sclerotia , and irrigation water supply is a vulgar author of transmission in commercial fields .
How to Manage Sclerotinia of Tomato
There are some technique you could use to minimise contagion of your plant .
Unfortunately , no resistive multifariousness of tomatoes are available currently , thoughgenetic testing of impedance to this pathogen is afoot .
When weather condition are favourable , it is a good mind to inspect your plants periodically and take and destroy any that show symptoms of this disease .
render the panoptic host reach of this pathogen , it is peculiarly of import to double down on remove any mourning band establish in or near your garden .
Cultural Controls
What ’s the most important constituent in term of ethnic ascendence in this example ? Location , location , location , as they say .
Rotate your crops and debar planting in filth known to be contaminated with this pathogen for at least five years . take note that the sclerotia can live late in the territory for up to 10 age .
If that ’s not potential , consider planting in containersor advance bed , using fresh soil .
Make certain yourgardening toolsare clean !
option include a solution of 10 percent bleach , 70 percent rubbing alcohol , or an trip oxygen product call BioSafe Disease Control that isavailable from Arbico Organics .
BioSafe Disease Control
If you produce your tomato plant plants in containers , sterilize the pots before using them again . Plant in fresh dirt to lessen the risk of exposure of possible contagion .
If you may keep the airfoil of the soil teetotal , you have a good chance of forbid the genus Sclerotium from sprout . raise safe drainage and keep pooling of surface piddle around your industrial plant .
snip your plantsto improve strain circulation , and do n’t plant your love apple industrial plant too close together .
This combination of heedful pruning and adequate spacing will reduce the amount of surplus moisture that stay on the leaf , allow it to vaporise more quickly .
Other proficiency to minimize moisture include space your rows wide , and cage or training your plant to maturate up trellises .
at long last , avoid water your plant life from overhead . It is good to practice asoaker hose at the primer floor , or drip irrigation , to avoid spraying urine on the foliage .
Commercial growers sometimes fumigate their grease . However , the chemical substance used are highly toxic to all form of life story – not to remark expensive – so this is something that you probably want to avoid as a dwelling nurseryman .
Some studieshave shown that ground solarisation for eight week during the summertime month can be effective .
Solarization involve laying a transparent sheet of plastic over the soil airfoil to apply the heat from the Dominicus to raise the temperature of the soil . The sheet want to be pulled tight to minimize airwave pocket , and weight down down at the edge .
If you are short on outer space and you must view set your tomato in the same plot next year , strongly believe digging up the soil after removing an septic plant .
Dr. Beth Gugino , Professor of Vegetable Pathology at Penn State University , recommends digging a circle around infected plants with a radius of six to eight inch four to six in deep in the reason , and take all of the grunge .
Dispose of it in the garbage rather than reusing the ground !
Biofungicides
Other option let in using biofungicides – treating the soil with microbes that will drink down theS. sclerotiorum .
Your basal option is a certified constitutive product call Contans WG that contains a suspension of spores ofConiothyrium minitans , a fungus that parasitizes the sclerotia .
This strategy works intimately as part of anintegrated pest management system .
You will necessitate to plan three to four months in approach to give the fungus plenty of time to aggress the sclerotia .
It is also critical to avoid till the ground deeply , or you run a risk bringing sclerotia bury late in the soil to the surface , where they may pose a threat to your plants .
Fungicides
Several synthetical fungicides are registered to controlS. sclerotiorum .
Endura ( boscalid ) is specifically labeled for gray mold , but is get laid to be effective against timberland rot as well . You should apply it in progress if you surmise that an onrush is likely .
Other options include Fontelis ( penthiopyrad ) and Botran ( dicloran ) .
The Combination of Spores and Sclerotia Is Deadly
snowy mould ( or quality guff ) of tomato has multiple ways of spread out to attack your industrial plant . Air can blow in spores or soil infest with sclerotia , which can then make more spores .
It is important to familiarize yourself with the other symptoms and keep a unaired heart out for this disease .
There are a number of ethnic methods you’re able to enforce to reduce the chance of transmission .
If you know your soil is infested with sclerotia , you may treat it with a biofungicide to parasitize and kill them . And you may preemptively habituate synthetic fungicide to prevent contagion .
Now , arm with this information , you are better fit out to keep this destructive pathogen out of your tomato plant garden .
And for more selective information onidentifying and treating common tomato disease , you ’ll need these guides next :
© expect the Experts , LLC . ALL right RESERVED.See our TOSfor more details . Product picture via Arbico Organics . With extra authorship and redaction by Clare Groom and Allison Sidhu .
About
Helga George , PhD
