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So Greg, today we’re going to talk about another group within the soil food web and that’s bacteria. Bacteria are really interesting because the way they associate with plants is a bit different. They’re not necessarily in direct contact but they can also be free-living organisms in the soil, and that’s quite a new thing of discovery for science right now. Yeah I guess for a long time we’ve known about the relationship between the rhizobium bacteria with legume plants, because they form nodules and if you pull a legume out of the ground you’ll see those nodules on the root and that probably got people asking “Well what’s going on here?”. There’s lots of free-living bacteria, various species that have similar functions and relationships with plants just like rhizobium, but because we don’t see something with our naked eye… Yeah there’s no evidence. Yeah. And now with DNA technology advancing and people are looking into the diversity of biology in the soil, we are discovering all these symbiotic relationships, but with free-living organisms that are just kind of hanging out in the rhizosphere. So, a lot of this relates to the rhizosphere so maybe let’s just focus on the rhizosphere and what that is when we are talking about that. Yeah, the rhizosphere is an area, up to maybe a millimetre or two away from root surfaces, and it’s a very diverse and biologically active zone in the soil. Whereas if you looked in the bulk soil you probably could find that there’s not a lot of life going on in areas, but there are some interesting things that happen around roots. Plants excreting different compounds that are food for these organisms and they can excrete specific compounds to attract specific species to serve a certain function that is lacking around that root for the plant. It’s so funny when you talk about how thin that layer is. It sounds like it’s very small but there is just so much activity. It’s really fascinating. So you’ve mentioned basically exudates, in terms of what the plant releases and also what goes back the other way. So, what are some of the benefits of those compounds and chemicals that can interact between plant and biology? So, just like you know with mycorrhiza, they are much more effective at solubilizing nutrients like phosphorus. We could say the same thing about some of these bacteria as well. Whether they also excrete enzymes that help to solubilize different nutrients that are unavailable to the plant root. Some of them release actually plant hormones that stimulate the plant growth, they will also release antibiotic compounds and penicillin is a great example… Yeah, penicillium. Yeah I mean, soil borne fungus that saved honestly a lot of lives over the years. So, you know, there is a lot of secretion happening, different benefits to the plants and to those organisms that are supporting the plant or helping it grow. One thing that people might be familiar with, but might have a misconception about in our industry, is the word biofilm. Yeah, I think that really comes from hydroponics and indoor production and that older way of thinking that the only thing there is your plant growing, there is no other life, we need to maintain these sterile conditions, and so you get these biofilms building up and they could contain pathogenic species. So it has gotten this really negative connotation, but in nature and in the rhizosphere there’s these biofilms forming, and they are biologically diverse and a lot of them are beneficial species as well. Yeah, you and I have a biofilm on us right now as we’re talking. These are very present in nature and very important for a lot of different organisms. It’s really important to understand for everyone that the biofilm is actually a good thing, as long as you are culturing it properly like you said. Murphy’s law, if you have a sterile situation and it un-sterilizes, generally you are going to get the things you don’t want first. So, to be clear we don’t want that to happen for people, but you do want diverse biofilm building up around roots structure. Yeah, and it think it’s… when you are trying to have a sterile environment, like you kind of alluded to, the first things that are going to come in could very well be those pathogenic species. As we have been discussing, the beauty of diversity and by having a biofilm that is full of different organisms, filling different ecological niches, and some are predators to others, that we can create this balance in your system that if those pathogenic species are present their impacts will be minimized. Yeah, the way that I sort of describe the biofilm when I’m trying to explain it to people is the idea that, think about a parking lot at Christmas time and how busy everything is. There’s only so many parking spots so if they are full nothing else can get in. So, if you fill it with beneficial organisms then you have a much better chance of actually repelling the pathogenic species because they can’t get that foot hold. The biofilm is definitely critical. You know, one of the products we have in the Grotek range that takes advantage of some of these benefits is Biofuse. And Biofuse is a two species, specific bacteria blend. What are some of the benefits that you can think of in terms of enzymes around the root structure? Enzymes they stimulate chemical reactions, right, that may not happen otherwise. They need a little bit of help, a catalyst to make them happen. A lot of those reactions are solubilizing nutrients and making them into a plant available form. Breaking down larger compounds into smaller molecules, it can be absorbed by the roots, some of those enzymes they maybe also have a kind of chelating or a complexing function and help to transport those nutrients to the roots surface for absorption as well. Yeah, by breaking it down but also putting it into the right form as well and I know obviously with Biofuse, phosphorus and iron and a couple of other micros are definitely freed up when those bacteria are present in the root zone. One thing that I think a lot of clients think about, and something that Biofuse can help with as well, is the fact that you can have enzymes that will break down cellulose. Essentially, breaking down sort of dead material around the root structure. Maybe you can talk about why that’s important. Well that’s important because any dead plant matter is going to attract decomposers and some of those may be pathogenic species. You can get certain organic compounds building up in the media and by having those bacteria there they help to break down all that tissue. And it will release some of that nutrients out of the tissue that can be reabsorbed and utilized by the plant kind of as a second go for nutrition. They can also be leached out if they aren’t needed by the plant. Yeah yeah, we’ve talked about beneficial fungi that do attach to root structure very specifically, but these free-living species can interact with those other species very well also. So it’s not really one or the other, you can definitely involve lots of different species for different reasons and most of them will actually interact quite successfully together. Exactly, everything has its ecological niche and nothing has evolved in isolation. So a lot of these different organisms actually benefit from being in the presence of each other. Yeah I know it’s super interesting. For all the gardeners out there that are watching today, I would definitely recommend considering not only those direct relationships, like with the mycorrhiza, but also things like Biofuse where you have those free living bacteria and take advantage of that for their garden.

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