For hormone treatment in short term (around 6-12 hours), 100uM jasmonic acid/methyl jasmonate is enough to induce plant. In case in a long term (7-10 days), which concentration is suitable for rice?
100uM -250uM JA is probably sufficient to induce responses in Rice, simply because this amount is usually inducing a response in most plant species. However, in order to do it right it would be good to have data on an endogenous JA concentration in response to a standard rice tissue damage.
Plants very in how strong and for how long the endogenous JA peak is. Thus in order to use JA/MeJA for any meaningful experiments, you want to have an idea on endogenous levels.