What is Orvan™? Coupling the aflatoxin and nitrogen problems in peanut
Orvan™ treats two of peanut farming’s hardest problems — aflatoxin and inefficient nitrogen — as one coupled question in the soil. It is built on the Aspergillus–Rhizobia Coupling research. Here is what it is, how it amplifies nitrogen fixation, and the science behind the coupling.
Orvan™ is built on Aspergillus–Rhizobia Coupling. It is a microbial consortium — a defined community of beneficial bacteria — applied alongside a rhizobial inoculant. One point matters up front: Orvan™ does not itself contain rhizobia. It works by amplifying the native or co-applied rhizobia already at the root, not by replacing them. The bigger idea behind the coupling is that it treats two seemingly separate problems as one.
Two problems that meet in the soil
Peanut growers face two costly problems at once. Aspergillus flavus contaminates kernels with aflatoxin, and nitrogen use stays inefficient. Historically these are handled by different toolboxes — fungicides and drying for one, fertiliser and inoculants for the other. Orvan™’s premise is that in the rhizosphere — the thin, biologically busy zone of soil around the roots — the toxigenic fungus and the nitrogen-fixing symbiosis are not independent. They interact, so an intervention aimed at one can move the other.
What Orvan™ is
Orvan™ is a defined community of beneficial, non-rhizobial bacteria — including strains such as Bacillus velezensis and Brevibacillus laterosporus — selected to work together in the root zone. None of them is a rhizobium: Orvan™ is built to work with the crop’s rhizobia, not to be them. All strains are spore-forming, which gives the product real heat and desiccation tolerance and a shelf life on the order of 12–24 months.
How it works, in brief
On the aflatoxin side, research examines how the community interacts with A. flavus in the soil and pod zone — through mechanisms such as competitive exclusion for space and resources, and the natural compounds these bacteria produce. The scientific question is whether shifting the rhizosphere microbiome before harvest can lower fungal load in the window that drying and storage cannot reach.
On the nitrogen side, Orvan™ improves the conditions for nodulation, so the crop forms more effective nodules and fixes more of its own nitrogen — without the usual trade-off between more nodules and yield. What matters in the field is that both problems move in the right direction from a single application.
The coupling insight
Why might the two halves connect? Picture a seesaw in the rhizosphere between the pathogenic Aspergillus and the beneficial nitrogen-fixing symbiosis. The hypothesis behind the coupling is that shifting the balance away from the pathogen improves the environment for nodulation — so the same intervention that supports the microbiome could also help the crop fix more of its own nitrogen. That coupling of the aflatoxin and nitrogen questions is the whole idea, and it is what the Aspergillus–Rhizobia Coupling name records.
What the field trials show
Orvan™ has been evaluated across multi-year, multi-site field trials spanning all eight legumes we serve and hundreds of sites, each crop working through its own locally-adapted rhizobia. The yield response is consistent across the range:
Orvan™ yield response by crop (multi-site field trials)
| Crop | Sites / provinces | Yield gain |
|---|---|---|
| Peanut | 325 / 19 | +19.9% |
| Soybean | 253 / 18 | +16.1% |
| Mung bean | 54 / 5 | +15.3% |
| Alfalfa | 96 / 4 | +15.2% |
| Common bean | 62 / 6 | +14.2% |
| Cowpea | 48 / 5 | +13.8% |
| Pigeon pea | 36 / 4 | +12.6% |
| Black gram | 30 / 4 | +11.9% |
The two flagship crops show the coupling most clearly. On peanut, the +19.9% yield came with over 80% less A. flavus in the soil in OCRI-CAAS trials; on soybean, +16.1% alongside elevated isoflavone. Underneath the yield, the symbiosis itself was transformed: nodule numbers rose up to 8.5× on peanut and 3.7× on soybean, and nitrogenase activity — the direct measure of fixation — up to 10.7× and 4.8×. And in dedicated trials over three consecutive years, Orvan™-treated fields held a yield gain above 10% even with 20–40% less synthetic nitrogen — the clearest sign that the biology is genuinely substituting for bought fertiliser.
The headline: across eight legumes, Orvan™ lifted yield by roughly +12% to +20%, multiplied nodulation and nitrogen-fixing activity several-fold, and sustained a >10% gain on 20–40% less synthetic nitrogen — and cut soil A. flavus by over 80% in the peanut trials.
How you use it
Orvan™ is applied at sowing and co-applies with NPK and with Nodu™ / Vigor™. It comes in several formulations to fit any planter — a broadcast granule at about 60 kg/ha, a concentrated microgranule at 5–10 kg/ha, an in-furrow liquid at 1–3 L/ha, and on-seed forms — all guaranteed to a live count of at least 10⁹ CFU per gram or millilitre to expiry. The handling rules are the same as for any live product: apply Orvan™ last, after any fungicide seed treatment, and avoid copper fungicides, strongly alkaline conditions (pH > 9), and chlorinated water.
What Orvan™ is — and is not
- It is not a rhizobial inoculant. Orvan™ needs rhizobia present to amplify; on ground that lacks them, pair it with Nodu™.
- It is not a chemical fungicide. It works through the soil microbiome, and complements — not replaces — good drying and storage.
- It is a coupling consortium: one application that amplifies nodulation and nitrogen fixation, and is the subject of our aflatoxin-coupling research.
How the three biologicals divide the work
| Product | Role in the program |
|---|---|
| Nodu™ | Establishes region-matched, nitrogen-fixing rhizobia |
| Vigor™ | Builds roots, unlocks soil phosphorus, improves stress tolerance |
| Orvan™ | Amplifies nodulation and nitrogen fixation |
In short: Orvan™ treats aflatoxin and nitrogen as one coupled question in the rhizosphere — amplifying the rhizobia the crop relies on, while our research investigates the aflatoxin side, in a single pass.