Disease in seedlings?
 

Hi All,

This is my 4th spring starting my plants from seed and I've never ran into issues up until this year. My plants are about 4 weeks old at this stage, being grown in my basement at a temp of around 60 F, had heat mats only during germination. Fan on intermittently throughout the day. Under high-intensity LED grow lights for about 14 hours daily. Everyone was looking good until literally the last 48 hours when 5 of my 20 starts rapidly developed twisted/contorted new growth and odd thickened/fleshy- almost gall-like lesions on the leaves. One of the plants had yellowing of its lower leaves but that alone wouldn't have really caught my eye. I immediately removed these plants from cells and disposed of them after taking pictures but I'm hoping to get some idea of what happened. All the seed is fresh and from reputable sellers who I have bought from previously. The seeds were planted into sterile media.

Any ideas? Thank you for your time

Is this the first time with those LEDs

We’re they quite wet? Are they supposed to be antho varieties?
I think multiple issues here, Ph issues? nutrient deficiency, edema, cold, lights too close?
Possibly seed borne virus but I think more likely cultural issue(s)
May I ask which reputable vendor?

What sterile media are they in, have they been fertilized?
KarenO

that looks like a lock of phosphorus because they are too cold. nothing more.

60º F is nowhere near cool enough to cause Phosphorus deficiency. I do agree with KarenO that it looks like other cultural issues. Looks like Edema blisters, too much water with plants too close together raises the humidity level around the seedlings to a point the plant can't transpire properly which can also interfere with nutrient uptake from the roots.

I should probably just stay out of it but, maybe just maybe it's the LED.
Are they floodlight shop lights or grow lights
I got twisty purple seedlings under LED flood lights, not bad as yours though.
[URL]http://tomatoville.com/showpost.php?p=689346&postcount=19[/URL]
Plus its not all of your seedlings?

When susceptible crops are grown under ultraviolet-deficient environments, such as light-emitting diode (LED) sole-source lighting that supplies only red wavelengths, intumescences are most severe. However, the incidence of the disorder can be diminished or prevented if crops are grown in environments providing ample blue or ultraviolet wavelengths of light. End-of-day far-red lighting has also shown some promise in mitigating the disorder.
[url]https://www.researchgate.net/publication/309777975_Light_Quality_Effects_on_Intumescence_Oedema_on_Plant_Leaves[/url]


Disregard if your lights are the same lights since forever.....

....& bower got edema under LED shop lights

[URL]http://www.tomatoville.com/showpost.php?p=690634&postcount=59[/URL]


[URL]http://www.tomatoville.com/showthread.php?t=46760&page=2[/URL]

They can also get edema under cxb 3590s which many weed growers consider being the best LED cobs, I know from experience. It seemed to be worse on the hybrids than heirlooms in my experience. The cxb 3590s work very well for lettuce though not for tomatoes. I’d suggest you move them under some T-5s , they will recover if not too far gone. Hope you can rescue them soon!!

ambient air temperature is not indicative of the soil temperature. 60 in a basement can result in 50 or less degrees media mix...which can still cause a lack of phosphorus uptake.

Your plants have edema. Too much watering, too cold, and too little light. LED's must be high quality with full spectrum.

"One of the drawbacks of LED clusters is that they are directional. This makes them ideal for spotlights, but not as well suited for ambient lighting. Their directionality isn't as noticeable inside a phosphor-coated casing, because the entire casing glows, but the bulk of the light still emerges from the top of the bulb. The quality of light that an LED emits depends on the circuitry of the bulb, and there's a large difference between bulbs. The best bulbs, which include high-powered circuitry, produce full-spectrum white light comparable to that produced by halogen bulbs -- high-temperature incandescents. Lower-quality LEDs can be comparatively dim."

[url]https://en.tomathouse.com/edema.html[/url]

60 ° F is low, no tomato can grow normally at this temperature. The minimum required temperature is 17 ° C that is 66 ° F.
Vladimír

I had the same problem with my seedlings grown under two 6500°K common LED bulbs (2450lm each) and a luminescent tube (1350lm), so the light was dispersed. Up to app 45 days from sowing they were okay (Nov 1 - Dec 15). Then the edema started to appear, but only in one variety out of six - Tomato Berry F1. There were 2 other hybrids and 3 OPs there too and those never displayed any symptoms like that. I was afraid that it was something infectious, so I quarantined them immediately. I transplanted them into larger pots with less fertilized mix and later I removed the leaves that went blackish. The plants now have flowers and small fruits. They were set back maybe 2 weeks, but they look okay now even though not very photogenic. The temps have been 68 - 70°F by day and 58 - 60°F at night. And I haven't changed them. The same with the lights. As to humidity I have no idea, but I sleep in that room, so it definitely hasn't been excessive. My conclusion is that I simply over-fertilized them and that the hybrid variety is more sensitive to it. The symptoms looked very similar - this is the early stage.

Milan HP


Ooops, I did make a change to the lights: I replaced one of the white bulbs with a red and blue LED grow bulb, 54W. The white bulbs are only 20W each.

Clearly that tray is toast. Start another tray upstairs in a different environment. Make room. It is just one tray. Sterilize your soil
in your oven. If your soil is purchased claiming to be 'soiless/sterile' it may not be. Old stock or bad stock.
Many here have had bad situations with tainted soil.

I had drama in 2017. Similar. I cleaned and sterilized my seed starting room...then found an upstairs shelf to re-start my seeds in my pantry.
I had a tainted 'clean' starting mix that was not such. Disaster until I started over with oven baked soil.

I don't think most diagnosis are easily solved. Sterilize your trays, sterilize your soil.
Plant more than you have room for and cull.

Yes, I do want to solve the reason for disaster. But I want success for the upcoming season.

I do run a small fan 24/7 but colder temps may have contributed to the downstairs 'drying out' ?.

I do have 3 dozen micros growing all winter and fruiting now....not sure what I did correctly....always learning