@Mark Reed (or anybody else) I have a
project for you that doesn't require bandwidth! If you're interested in this kind of thing. Here is part of a transcript from and interview with Dr James White about the science behind plants and
local adaptation. BUT-- maybe it's too technical? I feel like it has incredible information (if you can imagine this section below x 10) but nobody has read it! Here I am feeling like I'm sitting on this crazy information and I can't get anybody to read it LOL. So I feel like somebody needs to summarize it, somehow make it more digestable. In the course, pre-ceeding this section of transcripts is a 45 minute presentation on endophytes, so there is some background for people. Just email me let's talk more if you want
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(Section of transcript)
Julia: A lot of what we're talking about when growing landraces is about saving seeds and replanting them in the same location year after year so that they can adapt to that soil, to the conditions, to the weather. The plant microbiome is essential in the process, can you expand on how plants use endophytes to adapt to local conditions?
Dr James White: Plants are fishing microbes out of the soil, and they are training these microbes to do what the plant needs them to do. What do I mean by ‘training’ them? Plants are feeding them with nutrients, they’re putting that into the soil around the
roots. Certain microbes are attracted to the nutrients, and then the plant takes them in to the roots. But only certain microbes are compatible in that process. Certain microbes can become pathogens and the plant loses control of them, if there is no healthy community around the plant.
The plant has to get the genetic line of the microbes that it can get nutrients out of. Enough of that microbe can then survive in order to stimulate, repair, develop and then be injected back to the soil (in greater numbers) to get more nutrients and then track back. That's the rhizophagy cycle, so it has to work in the rhizophagy cycle.
The plant is selecting those microbes that work best with it, in in its tissues. And so the microbe that is ideal for one plant, may not be ideal for the next, because the plant selected that microbe.
JW: I would agree that it makes sense to get the varieties that are adapted to the local regions, for a lot of reasons. Maybe the genetics of the plant is part of it, but the microbiome may be another part of it. And I would also suggest that what is typically overlooked with plants, is that the microbes are a big part of the plant immune system, so if we get the right microbes in those plants, they're going to be resistant to fungi, and resistant to other kinds of pathogens.
If you get the right microbes in those seeds, then they're going to be able to acquire the right nutrients out of those soils that they're adapted to. Where there is a history of growth in a specific location, they will have gathered particular microbes that enable them to get particular nutrients that are hard to get out of those soils. The plants are adapted to that area. Part of the adaptation is getting the right microbes that carry the right nutrients and the training those microbes for optimal performance in the plant. The plant really selects these microbes: If there's an iron deficiency in the soil, that the plants that are going to thrive in that soil are the plants that get the microbes who carry iron and bring it back to the plant, and those are the endophyte that do that. If you’re going to grow in that particular soil that is low iron, you want the microbes that can carry iron to be the endophytes in the plant. It's better to get plants that are adapted for a particular region, with their microbes adapted to that region, than plants from a far distant area. That doesn't mean you can't adapt a plant. You could get a plant from somewhere and start it growing in a different location. Typically, it doesn't grow as well at first, it takes some time to get it grow, but you could probably get the right microbes there.
When I was talking about plants taking microbes in, there's a selection that happens that I
should say more about. Let’s say if a plant acquires a microbe that is too oxidatively resistant, it's not susceptible to being controlled by the plant using super-oxide. What happens is that the plant doesn't grow. It doesn't reproduce, so it dies. Seedlings don't even grow. Or let's say they go into the plant, and they're resistant [to the super-oxide from the plant], they don't lose their cell walls when the plant puts superoxide on. (Normally [in the rhizophagy cycle] what the plants do is put superoxide on the microbe and they lose the cell wall and become these naked protoplasts. The plant can then replicate these naked protoplasts, get nutrients out of them, replicate more and make a lot of them. And then they get ejected out into the
root hairs, out of these little pores back into the soil). Well, if they don't lose their cell walls, they don't replicate, so there's not a lot of them in there. And also, they can't be ejected out because the pores at the tip of the root hairs are really tiny things, and only a little naked protoplasm can go out of that root. So these ones that aren't responding, if they go in, they don't get replicated and ejected. The plant selects those out. It selects specifically for the ones that work with this process, and the ones that are bringing the right nutrients to it, enable the plant to then grow better, and then those plants, with those endophytes, they succeed. So there's a selection, they are training those microbes to work inside as endophytes, and then populating the soil with those microbes, so that the plant can thrive with getting more nutrients from those microbes.
It's a very important process, and almost automatic the way the selection works with these endophytes. The plants really are selecting specific microbes, and cultivating those as endophytes, so they are managing those endophytes in that process called the rhizophagy cycle.
Julia: In my field, I have really high aluminum, low calcium and it’s acidic and sandy. And if I don't give the plant's calcium and
compost, they don't grow, or they die. If I save seeds from the plants that grow year after year in that same soil, would the plants be able to teach the microbes to protect them from the aluminum and scavenge what little calcium there is, or, how much can I expect?
JW: Yes, there are endophytes that will carry a lot of calcium, but also that will carry a lot of aluminum. You don't want the aluminum ones, you want ones that will take the aluminum and not bring it back. You can find those endophytes that do that. I think what you would want to do in that case, is to find wild plants in soils with high aluminum and low calcium, and then get the endophytes from those plants. Take some of the seeds from there, then plant those seeds with your seeds. That's my idea about planting the seeds together. Try that, get the endophytes off of those seeds get them into your crop and see if you can get plants that are growing in that low calcium environment where you don't have to keep putting calcium in. You might you might see a big difference if you do that.
Julia: Also If I’m I saving my seeds, then after maybe three years, then I should have trained endophytes and trained plants?
JW: I don't know how long it'll take. It took us a long time to screw up the microbiomes of plants. We might not be able to get it back two or three years. Walter [Goldstein] has put a lot of effort into it. He's actually added endophytes to his corn. He told me he got some bio-stimulant endophytes from Brazil. He put different mixes of endophytes from sugar cane and some other crops in Brazil. So he's actually working hard to get those endophytes back into his corn, in addition to growing them in biodynamic conditions.
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