I have been interested in starting these from seeds this year, and after reading posts here, I see that some people find the seeds and plants of these 2 species similar.
First of all, true Musa Nagensium is one huge banana. Equally, the seeds are supposed to be much larger than sikkimensis, about the size of ensete seeds.
Musa cheesmani has seeds about the size of sikkimensis.
I think Tropicalvr posted a photo on the gardenweb/banana forum, where he has lined up seeds of different musa species, showing size and shape. (Thankyou Tropicalvr!) What struck me here is the relatively small size of musa nagensium, compared to the other species. But now I may have solved the mystery!
I have contacted the main source of banana-seeds for seed-dealers, who is located in India. The answer to all the confusion lies in yet another hybrid. He offers "Musa NagensiumX" AS WELL AS "Musa Nagensium "true form""- IOW,2 types of the same species. Who knows wich one the online seed-dealers put out for sale? This critical difference may not show up on the seed-dealers internet-stores. But it shows up when you get small seeds in the mail, 2 weeks later!
My theory is that Musa NagensiumX is a hybrid between "true form", and Cheesmani. I think they share an ecotype(?), and people report similarities between their Musa Cheesmani and Musa Nagensium.
What do you guys reccon?
erlend