We all know that our legumes need to be inoculated to ensure maximum nitogen fixing by the roots - however can anybody give me an answer to the following questions: - How is the inoculant that is provided in the peat moss powderred form produced? - Is it possible to take the bacteria from root nodules in one location and apply them to a new planting in a new location? - What leggumes have the same inoculent? The reason I ask these questions is that invariably my inoculent expires before I have finished using all my seeds. Also I would like to be able to save seeds and be able to inoculate them. Inoculent is not readilly available for purchase by itself (ie without the seeds). I'd like to know much more about this topic.
Yes and no. Yes, you can culture your own inoculum without too much trouble. However, specific species of legumes require specific species of rhizobia. What grows with alfalfa, will not grow with soybean etc. There may also be some varietal specificity though this is less likely. It is worth reminding people that contrary to common expression, legumes do not fix nitrogen. They provide living spaces (nodules) for rhizobium bacteria which do the nitrogen fixing. Equally, just because a plant has nodules, does not necessarily mean any bacteria have moved into their subterranian apartments. There are also native species of rhizobium which are generally believed not to be as effective as nitrogen fixers. Lazy buggers. What has not be effectively researched though is what other beneficial characteristics these native dudes may have. They may have localised adaptions which could be utilised in hybrid populations. If you have a legume plant with existing live nodules, then you can harvest these to cultivate additional symbiotic nitrogen-fixing bacteria. The colour inside the nodule will usually indicate whether it is active or not. Red/pink good. Green/white, not so good. As you indicated inoculum is relatively short-lived and best used. However, basic culture of these beneficial bacteria is simple. A couple of methods possible. A simple but crude method is to collect viable nodules and handfuls of soil around said roots. Roughly crush the nodules. Mix nodules and add 1/3 to 1/2 (by volume, no need to be too precise) with add 1/3 crude sugar. Molasses is usually the cheapest form of sugar. Put this mixture in a flat tray or tupperware container keeping a 50-75% air gap between growth medium and the cover. Cover loosely and let the mixture ferment for at least a week. Bacteria need oxygen too so do not suffocate them. (Longer if weather is cool). After a while you will see molds and microbial infections growing through the medium. There should be sweet sour, perhaps alcoholic smell. These are good smells, like fermenting beer or rising bread dough. If there is a foul nasty odour, the mix has gone bad and needs to be discarded. When you have good growth happening, strain the mixture. The liquid generated will be rich in both rhizobium and other beneficial soil microorganisms. This can be used to inoculate fresh seed prior to planting. Any leftovers can be put onto the compost heap. There is no hurry with this preparing this mixture. The longer you let it ferment, the richer it will be. The sugar in the mix will keep feeding the resident microorganisms. When treating fresh seeds, you may need to use a sticking agent such as corn syrup, milk or powdered milk. Keep in mind that this is a rough but effective 'shotgun' method. The purists and academics will say, with some justification, that you do not know what exactly you are cultivating or how 'strong' the solution is. Truthfully, a pure lab culture is a much more controlled product. And more expensive! However, this method has been used by traditional asian farmers for generations. A counter arguement to the purists is that locally cultured microorganisms are far more likely to be pre-adapted to local soil environments. Also, natural microorganism communities are extremely diverse symbiotic populations. Pure cultures of individuals species do not generally occur in the wild. So a localised 'shotgun' culture is more likely to contain mutually supportive 'friendly' populations. Similar to the monoculture/polyculture arguement of permaculture. I have somewhat simplified the process here, but the basics have be covered. In the interest of giving due credit to sources, I 'dips my lid and tug the forelock' in acknowledgement of my mentor in such matters, Gil Carandang of Philippines. Cheers
Nice to hear your response James, I have never heard it explained like that b4... it's kinda of like one of those mysteries your not really sure you should question or not without looking too dumb! Perhaps you can ask the ppl you bought your seed from Vegie and see what they have to tell you.... then you can let us all know (ie.... whether it was seed from Green Harvest who i know provide inoculent with their seed, i actually have found their seed very viable!) Cheers... Dave
I have purchased cow peas from green harvest and have received the required inoculent with the seed. I have had no problems with green harvest seed or inoculent. The problem is that I have a significant amount of seed leftover and would like to use it this year - though the inoculent has expired. I was interested to see if I could amke it up myself from the nodules, therefore enabling me to plant new crops in different areas with leftover or saved seed. James - your response is great and I will be sure to try it out. Before starting to use green harvest, early in my very short time experimenting with permaculture (about a year ago), I purchased substantial $ worth of seed from another provider (who shall remain unnamed). I was vaguelly aware at the time of the cocept of inoculation and the catalogue stated that the legumes that I was purchasing came with inoculent. When receiving my seed purchase (which included sevral legumes (lucerne, pigeon pea, broad bean) as well as veggies etc, I received no sperate packs of inoculent. I incorrectly assumed - being very new to this stuff - that the seed must be dusted with inoculent. When I realised later down the track that the seed could not have been dusted - as the inoculent has a short life - I contacted the seed supplier. I had already planted much of the seed (some several months earlier) and was disappointed that they had not been inoculated. My seed had come over 2 seperate purchases and neither time had inoculent been supplied - dispite catalogue claims. Clearly the staff were not properly trained in what was required. When I asked for replacement legume seed, the owner told me that such a request was the same as asking for a new car if you received one without tires. He told me I was the worst/most difficult customer her had had in the many years he had been running the business. He suggested that he send the inoculent and that I apply it to the crops with a watering can. Needless to say I have never purchased seed from that mob again - and have since found greenharvest. In fact the bloke told me that he would never sell me seed again - I was dumbfounded at his bad attitude and was surprised he had been able to survive in business. I had in no way abused him or his staff - he had simply taken offence to my request for new seed - given the companies failure to provide it with the required inoculent. I'm very tempted - as I was at the time - to tell group members the name of the company. I'm sure some people would be quite surprised - or maybe they wouldn't?? The only reason I don't is for fear of defamation claim. Anyway - as an aside and out of interest, would it be effective to apply inoculent to the crop through a watering process after it had been planted and had been growing for some time. Not that it would be practicle if the crop is of reasonable size - as was the case with the area I had plantd out with lucerne.
If you already have viable inoculant, you can culture from that source. It should stay alive (and multiply) for as long as it has a nutrient source (ie. crude sugar). Over time, the microbial populations may change and become less viable as an inoculant. Watering mature crops. Legumes play host to rhizobium to enhance their own growth. Enriching the soil for other plants is just a byproduct. Hence, the earlier in the plant's life that the rhizobium become active, the more benificial to plant growth. The ability for mature plants to absorb rhizobium is somewhat dubious. One viewpoint is that native rhizobium will have already moved in, displacing any late arrivals. Another is that the nodules themselves may become resistant to intrusion after they have matured. Watering in rhizobium. Certainly cannot do any harm. However, for field application, it is unlikely to be a very efficient or effective method. Rhizobium are small sessile buggers. Asking them to migrate through several feet of soil is big ask. Dilution rates is also another issue for similar reasons. Hand watering close to the root zone would be more effective, especially for potted plants. Still, no comparison with direct seed innoculation.
Veggieboy, I would like to know the name of that company for my own interests, just so I would know not to bother with the bother of ordering seed from them as I am fond of growing from seed. Perhaps u wouldn't mind sending me the name in a private email to avoid defamation worries. As another point of interest, recently I obtained some rhizobium from a company called BIO-CARE, they sell innoculant on its own & they have many different strains for different crops and they list the crops that the strains are suited to. I found them most excellent to deal with, they sent me heaps of rhizobium for free in the name of education! :shock: (as I'm doing a rhizobium/legume effect on plants grown in immediate vacinity trial at Swinburne) If u want to take a look try https://www.bio-care.com.au/main.htm Thanks for your really helpful info James, I always wondered about making your own innoculant too. Marika
There was a bit of discussion on this topic a while ago, so I thought I'd drag up this old thread. Tam
