Strengthen the immune system in our plants

[Cach26]

Hello everyone

How can we ensure that our plants develop a strong immune system?

I have read about different points of view

1) Use Thricoderma as a Bodyguard Mushroom

2) Make "organic fertilizers" with mosses and biological fauna that would be in their in situ environment to develop defenses, among them they use worm humus

3) Norman Fang's approach. Do not use Strong Fungicides. Have a good, clean and neat culture to prevent problems. And use very diluted Physan

However, I don't have Physan XD. I only have Ridomil available on hand

[Clawhammer]

Norman "do what I say and not what I do" Fang strikes again.

The best way to ensure your plants have strong resistance to pathogens is to ensure their cultural needs are all met.

[thefish1337]

I haven't used a fungicide ever, and rarely deal with pest and disease. Some of that is thru environmental controls growing indoors (I keep the humidity 50-65 with good air flow). I also attribute this to a few things:

1) PGPRs- I use a consortium of bacillus from Impello Biosciences called tribus which is the best bang for your buck. I have used quantum but that product was only recently updated to the current decade so I'll go with a product that people growing serious cash crops actually use. These microbes chelate nutrients, fix nitrogen, solubilize phosphate and potassium and produce compounds which can inhibit fungal and pathogenic growth. They also stimulate the plants immune system and you can read about it on Google scholar just search ISR ( induced systemic resistance) and/or SAR (systemic acquired resistance) and PGPR.

2) Lactic acid bacteria- can be purchased as EM-1 and amplified OR you can make yourself (look up LABS on YouTube). No need to over use but LABS have antifungal and antibacterial properties and are so vigorous they can dominate the rhizosphere and phyllosphere. If you notice you see diseases in certain conditions apply a 1:1000 dilution weekly, and prior to when you expect disease. Very good at stopping rot in its tracks and colonizing anaerobic acidic environments. Also induces systemic resistance.

3) Beauveria bassiana - Mycotrol is the commercial product but you can purchase some types not labeled for pesticide use from Build a Soil and some other places. This is a mycoinsecticide but also seems to promote orchid health once the spores to germinate and go into the plant. It takes repeated applications to colonize your plants and to reduce insect pressure but once that happens you will rarely notice a pest and they pests will always struggle to ever develop into an infestation. May also induce SAR and/or ISR

4) Silicon. The cheapest form is potassium silicate but it doesn't stay in solution very long and has a very high pH. Aim for 10-20ppm Si. There is mountains of research on silicon and plant defense. I use it during active growth of roots and shoots. Some say it doesn't work but orchids grow slow and it takes them a while to start incorporating silicon into their tissue- many bacillus can also help solubilize this when it inevitably falls out of solution. There are new (more expensive) forks that may work better like stabilized silicic acid and nano silicon. It can be easy to overdose these new products so start slow I am testing nanosilicon next growing season based on some new research I've read.

5) Biostimulants- plant extracts, amino acids and chitin/chitosan. I have tested out kelp extract (kelpmax is the only good one) and aloe vera extract with good effects on plant vigor. Also of note are amino acid preparations like soy amino acids and fish amino acids which have a number of anti-stress effects and can stimulate plant microbes. Tryptophan is a major substrate for the production of IAA in PGPRs. Glutamic acid has some interesting research behind it as well. Do not over apply biostimulants! Chitin/chitosan the major polysaccharide that makes up fungal.and insect cells walls is another major elicitor of plant defenses and has been researched on orchids.


Hope this helps. It takes time for your plants to develop these relationships with organisms and the best time to inoculate is early on in a plants life, the second best time is now. Your plants should never rapidly die on you if they have their immune system properly stimulated (over use of these things I've listed can dedicate too much resources to plant protection pathways esp chitin). The natural state of plants is to be colonized by bacteria and fungi and a big reason why plants in situ are very hardy despite looking pretty rough in some cases. Just using salts in soilless media certainly works but your plants will always be weaker and susceptible to disease compared to plants grown with beneficial bacteria. Over use of nitrate makes your plants much tastier to pests, better to reduce the amount of fertilize and use microbes to get back what you reduced. The amounts of chems people are dumping on their orchid collections, and constant use of fungicides and pesticides is terrible runoff into the environment but that is the traditional way it's been done and old habits are hard to break.

[estación seca]

• Proper growing temperatures.
• Excellent air circulation.
• Proper light.
• Proper humidity.
• Proper watering.
• Proper nutrition.

Other methods will not compensate if these are not met.

[Fairorchids]

My dad had his own nursery from 1948-1977, he never used a fungicide.

I have grown orchids from 1968-1977, and again 1994-present, and have never used a fungicide.

Finally, any info that comes from Mr. Fang is highly suspect (as are his plants).

[Roberta]

Except for Physan that I use to deal with algae on the greenhouse floor (so I don't slip and fall), I don't even own a fungicide. Never have used (in 25 plus years), or needed to use, fungicide on orchids. Outdoor breezes (and fans in the greenhouse) keep the air moving. I water a lot, things are pretty wet, but that doesn't seem to be a problem. With no problem, no remedies necessary.

[Clawhammer]

On FB AOS page every ailment requires a systemic fungicide, cutting off a leaf with spots, followed by H202 and finally sealed with cinnamon. Its pretty comical.

[KatieM]

How often would you apply the Beauveria bassiana when first getting started and how many times? How often do you apply a maintenance dose after established? Great info!

[Leafmite]

I do not use fungicide on orchids but I have discovered that many of the orchids I grow need extra Calcium as a preventative.

Some plants really do require regular applications of fungicides. I used fungicides (Captan) for the fruit trees when I had them (over thirty years) because when we skipped a summer, the fruit was not edible and the leaves were badly spotted and dropped. I use a granular rose systemic that has a fungicide with the roses because, well, roses.

[Jmoney]

on a related vein, does anyone has any experience with the dynagro product Protekt? It is claimed it strengthens cell walls, presumably improving disease/pest resistance.

I suppose the only "evidence" might be anecdotal at best, just wondering if anyone has seen any effect.