Hi Belachew!

Take a look at this paper: https://www.researchgate.net/publication/259590815_Eucalyptus_globulus_Leaves_Incorporated_as_Green_Manure_for_Weed_Control_in_Maize?ev=prf_pub

Regards!

Article Eucalyptus globulus Leaves Incorporated as Green Manure for ...

You can  view my article :Lantana camara equous extract of different parts on growth of P.hysterophorous. and other articles on researchgate.

Belachew, 

We did a study many years ago that may be helpful if you are designing an initial bioassay.  

Back in the 1980's there were lots of allelopathy papers and everyone seemed to have their own system; so one lab would find a molecule to be allelopathic but another lab would use the same concentration in a different bioassay and find that it was not.  All we did here was show that the difference appeared to be due to how much allelopathic agent each seed experienced. So 5 seeds in a large petri dish with a large volume of extract got a much larger dose than 5 seeds in a small dish with a small volume (though the concentration was the same).  And 25 seeds in a dish got 1/5 the dose if only 5 seeds were in the dish; so this was leading to the conflicting reports.  The green manure paper  Elisa pointed you toward is impressive, but may be beyond the scope of what you hope to achieve with your study.  It all depends on what you're hoping to do at this point, so perhaps a simple petri dish pilot study would be more helpful (we did look at germination rate and radical length).  I'm not a weed scientist, so I'm not sure what the standards are for the field now - so our old paper is probably more useful for historical context and may help you plan a design that gets your work started.  

https://www.researchgate.net/publication/259155313_Solution_volume_and_seed_number_Often_overlooked_factors_in_allelopathic_bioassays 

Article Solution volume and seed number: Often overlooked factors in...

This can be done by relative toxicity to a sensitive species like cress following the protocol of franco Zucconi et al. in Biocycle 1981. In practice you should amend a substrate with doses of E globulus leaves, take centrfugates at different maturations and evaluate cress germination and wheat's one in comparison This would eventually give a specific resistance and dose limits. A scholar issue is attached, http://scholarsresearchlibrary.com/ABR-vol3-iss2/ABR-2012-3-2-1094-1101.pdf