Have you already tried mechanical scarification? It works in most of the cases for Medicago species.

Thank you Peter for your respond. I will definitely try mechanical scarification using sand paper but I am unsure about it's efficiency. Do you recommend any additional treatment which may aid mechanical scarification ?

@ Paudel,

Any idea of the type(s) of dormancy exhibited by M. trunculata? A suggestion of dormancy breaking method will depend on your response.

Thanks,

Dear Mahendra Paudel ,

Yes, there is another way to stimulate germination. This is a short-term heat treatment. We applied it successfully for seeds of Anthyllis vulneraria. However, it is a risky method, needs preliminary experiments to decide the length of heat treatment and the appropriate temperature. Otherwise, the seeds can easily die due to overheating. So thus, I would suggest you: do not worry about mechanical scarification. Scarification is best done in such a way that it causes only mild damage to the seed coat. Because of this, some seeds may not germinate after the first treatment, but this is not a problem. After a week, you can repeatedly subject non-germinating seeds to mechanical scarification. In contrast, scarification that is too strong can damage the endosperm or the embryo, which can lead to abnormal seedlings or even the death of the seed.

Dear Dèdéou Apocalypse Tchokponhoué The seeds of Medicago trunculata exhibits both physical and physiological dormancy.

Thank you Péter Csontos for wonderful suggestion. I am thinking of treating medicago seeds with heat (90 degree C for 3 minutes) as my preliminary experiment. It would be wonderful if you could share what temperature and time duration was best for Anthyllis vulneraria.

Peter has already suggested heat treatment that works quite well in many Fabacaeae. One further suggestion would be dipping seeds in boiling water for a short period of time (e.g. 1-10 seconds). Works very well in e.g. Trifolium spp. Needs some experimentation with the treatment duration.

HTH,

Sergey

Dear Mahendra Paudel ,

Sorry for late response.

In our experiments with Anthyllis vulneraria seeds treated in hot water the best treatments were:

Temp.: 80 Celsius, duration: 10 min., germination: 16.6%.

Temp.: 95 Celsius, duration: 2 min., germination: 15.2%.

Related paper in Hungarian with English abstract:

Article Hőkezelés hatása a nyúlszapuka (Anthyllis vulneraria L.) mag...

Best wishes,

Péter