commodities movement follows only one priciple that is demand & supply. whenever there s a gap in that, price moves accordingly up or down.
urad game started right after cruel moonsoon in maharashtra and other urad growing parts. destroying almost 80% crop. So that leads to a move from 1750 to 3020 in a record time thanks to burmese traders, they also cashed this golden opportuniy and stop selling urad to india for some time(that was a huga scam).
so with some big local players here, burmese+local traders made crores thanks to our (blind)futures market
also u see more fluctuation in commodities which are very small.i.e. grown in limited quantity. like guar,mentha,urad,tur etc. this small crop size made them very easy for stokists to pile up stock, make cartels and move the market on their fingures. now a days by + and - buttons on terminals
i hope ur doubts are cleared.