c2h6

The issue that's confusing is the common misconception equating seedlessness (parthenocarpy) with being triploid. The two are actually unrelated for the most part. I imagine being triploid enhances the sterility, but diploid and tetraploid bananas can be seedless if they carry the parthenocarpy gene. So what is being suggested is to use a triploid as your female with a modicum of fertility carrying the parthenocarpy gene, and then use the wild M. balbisiana (or whatever variety) as your source of cold hardiness. The resulting offspring may result in a seedless, cold hardy, and hopefully edible banana. A lot of the banana breeding programs use triploids as their females, and possibly as their males, too. I agree that in a breeding quest for a cold hardy banana you should also consider the short cycle bananas.