c2h6

Turns out bananas are more complicated, in that the genes for seedlessness (parthenocarpic) is separate from triploidy. Triploidy increases sterility, but triploid bananas can still set seed, just very low numbers of seed. Tetraploid and diploid bananas can also be seedless, ie pisang lilin is a parthenocarpic diploid and some of the FHIA hybrids are seedless tetraploids. Because people selected varieties which they didn't know we're triploid, triploids seem to have a good mix of increased size from the gigas effect (from the increased ploidy) as well as enhanced seedlessness from being highly sterile.