Beneficial fungus & fungicide

[Stray59]

Hello everyone - hope your having a good weekend!
I have a question that I would like others to weigh in on. I know about the need for specific fungi to be present for the micorrhyzae to form for seed germination, but it is also noted that orchids will maintain the fungus in their roots into adulthood, with little research in this area as the any benefits from this continued relationship.
So, when you use fungicide, realistically the possibly-beneficial fungus would also be eradicated, wouldn't it? And especially if a systemic is used, I would suppose. So, has anyone every seen a difference, perhaps in overall health or vigor, between orchids that have had fungicide regularly applied and those that no fungicide has been used on?
Just pondering this as I relax with some coffee.........

[WhiteRabbit]

[Ray]

All plants have populations of microorganisms in their rhizospheres, both bacteria and fungi, and some estimates say up to 300,000 species at a concentration of 10,000,000 per cc.

Yes, fungicides and general disinfectants tend to be non-selective, so kill everything.

As I have learned more about this subject, thanks to the folks at Inocucor, I am coming to the realization that my use of Physan, for example, was like using nuclear warheads on situations that might have warranted a fly swatter...

It really all comes down to culture.

Healthy plants, in a healthy environment, given proper culture, are not going to succumb to bacteria and fungi as readily as those that are overcrowded, improperly fed (too little or too much), have no air movement, stand around wet, etc. Unfortunately, very few of us have the skill and/or capability of providing that ideal of a situations, so our plants succumb. And that's when we drag out the "nukes".

A bit over four years ago, I got serious about that, and cut my feeding significantly. I was unwittingly keeping my plants "obese" through overfeeding, and always fought rots, with the side effect of getting little blooming, besides. Then, about 2 years ago, I started a regular monthly regimen of adding a "plant probiotic" supplement to my very dilute fertilizer, and the results of both are outstanding.

AND, I haven't used a disinfectant or fungicide in the greenhouse since.

[terracotta7]

What would an example of a plant probiotic be? I mean...when I have to take an antibiotic I always try to balance that by eating more yogurt. Is it the same for orchids?

[thefish1337]

There is a number of studies that support the idea that complete sterilization dose not necessarily produce positive health outcomes in plants, humans or animals. being over hygienic allows a surface, or the microbiome to reset and become recolonized again. this is like secondary or primary succession in ecological terms. if you cut a hole in the canopy of a rainforest you get recolonization of the newly sunny spot, in areas of high diversity this can be somewhat random in nature- and this applies to microbiomes as well. the main difference is that microbial diversity is much higher than we can possibly imagine, Ray has expanded on this. Orchids are highly evolved members of the plant kingdom and have diverse relationships with fungi and bacteria applying systemic pesticides is not a long term solution because you always run the risk of recolonization with bad bacteria. you can also see this idea at work in a fish tank- fish tanks are not functional until populations of nitrogen fixing bacteria are sufficient to handle ammonia produced from fish waste and organic decomposition. i have also noticed anectdotally that there is bacterial "succession" in my fish tanks and when the tank water reaches a particular smell (earthy) i consider it mature. i have expanded this to my orchids; smelling the media of your orchids can provide you important information about bacterial and fungal population in the rhizosphere. if you notice that the smell of your orchid media has drastically changed from an 'earthy' (this is subjective but if you go into a forest you CAN smell the soil and you will know what i mean) smell to a rancid or off smell it is likely that you have disturbed your microbiome in some way.

[Stray59]

Thanks for all the input everyone. Personally, I don't use chemicals until it is obviously necessary. For fungus, I have found a strong air current is all I need to keep that at bay, along with making sure my media is not decomposing and allows good air to the roots.
Ray, you seem to have the same results as I did - I used to keep a schedule of spraying, whether it seemed to be needed or not. Since I have stopped with the "schedule", I thought my orc's seemed to be looking better.
Good to have all the info everyone! Thanks!

[Subrosa]

I received some Innocucor from Ray and have thus far seen good results in reducing damping off of succulent seedlings. Damping off is when a seed germinates, starts growing and then suddenly falls over, having rotted right at the soil line. Succulents are VERY prone to damping off and I was losing most of what germinated. I've been using it on my orchids as well, but the real test of a flask of Dendrobium subuliferum seedlings was interrupted by a cat eating the seedlings. At this point I give a reserved thumbs up to the product, but a more scientific experiment is soon to begin.

[Ray]

Originally Posted by terracotta7

What would an example of a plant probiotic be? I mean...when I have to take an antibiotic I always try to balance that by eating more yogurt. Is it the same for orchids?

I just happen to be working on a talk about "Biologicals in Orchid Growing"..

There are a variety of beneficial fungi and bacteria that function as "plant probiotics", but because of the difficulty in trying to get them to work together, rather than compete and do each other in, most commercial products contain a single species.

For example, Rootshield is loaded with trichoderma, which parasitizes other molds and fungi, and Quantum orchid contains a species of bacillus. About the only commercial product that contains a wide variety of fungi and bacteria is the Inocucor Garden Solution.

That's important because, in addition to their "curative" properties (i.e., killing the "bad bugs"), it is their metabolites that stimulate plant growth and defense mechanisms. The more species living in the rhizosphere, the greater the variety of metabolites, so the broader stimulating and protective effects on the plants.

To be perfectly transparent about this: First Rays is the sole retail outlet for the Inocucor product in the US, but folks who know me understand that I carry it because of its unique benefits, and am not just trying to "sell" it. I don't sell anything I don't use and believe in, and I do a lot of research and personal testing on my own plants before recommending stuff.

[thefish1337]

Great short read on orchid fungus interactions (specifically mycorrhizae)

Mycology - Mycorrhizas - Orchid Function

[terracotta7]

OK. That was what I was looking for! Just as different yogurts have different bacteria, so do different products for orchids.

For the first time I am having trouble with pbs on my oncidiums rotting. I had put it down to an unusually cold winter and the stress of the dry heat as well. But now I am thinking that they might need a boost of "good" bugs rather than a dose of "bad" bug killer. Hence my elementary yogurt theory!

Thanks