28
May 2019

Blight

Blight

Like clockwork, it has reappeared

 

Like it was scripted, I have been alerted of the first suspected case of Blight in a tomato crop.  I went and had a look and took these photos below.  Please be vigilant as the weather is perfect for Blight.  Don’t hesitate to go to your local horticultural supplier and purchase the necessary products to treat Blight if you see it.  Remember Blight = Plant Destroyer.  It will rip though a crop in a matter of days if left untreated, however if treated it is controlled almost as fast.

Above photos taken 28/5/19 

 

Below is from article written last year 21st May 2018:

Prevention is key but that doesn’t help once you have Late Blight, especially seeing how it can severely affect your crop in less than 48 hours.  You can have the best hygiene in the world but if your vents are open nothing will prevent spores from entering your greenhouse.  However, good hygiene practices are extremely important.

Unfortunately, it is hard to pinpoint what products you can use that are biological or organic to eradicate Late Blight once you have it. Copper products could control or slow down Late Blight epidemics but full coverage of the plants is required.  The Phytophthora infestans sporulates can survive on top of or underneath leaf surfaces.  Is there a way of protecting your crops with biological products?  

There are conventional preventive fungicides available, as long as you can use these products, and not exceed MRL’s (maximum residue levels), then I would recommend using them until we have better understanding and availability of biological products.   Personally, biological is the direction I hope we are able to take as an industry.  However, we must not dismiss chemicals and need to make sure they are our safety net, especially if biological products can not quite keep funguses like Late Blight in check.   I am concerned that there might come a day the chemical fungicides will not work as well, so using biological in conjunction with chemicals could extend the life of certain chemicals we currently rely upon.  It is a discussion I would like to have with growers and receive their thoughts.  

To read full article click link below:

news/post/blight-is-back–react-and-prevent/

 

 

I appreciate your comments.  Please feel free to comment below or on the grower2grower Facebook page:

https://www.facebook.com/StefanGrower2grower/

Article Written by Stefan Vogrincic, Consultant, Grower2Grower

Article Edited by Marie Vogrincic, Editor, Grower2Grower

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