PALERMO, Sicily — The stands overflowed with Sicilian blood oranges and almonds. Mediterranean mussels gleamed black. Taut yellow strings connected the tail fins to the grim mouths of sea bream, their silver backs curved like commas. Vendors interrupted their Sicilian warbling (“It’s her that I miss”) to tempt passers-by with traditional cartilage salads or spoon out spleen sandwiches over smoky grills.

But many of the immigrants shopping in Palermo’s Ballarò market on a recent afternoon bypassed the Sicilian staples and went for heaps of hyacinth pea pods that Bangladeshis call sheem.

The pods used to be imported, said Sumi Dalia Aktar, a local Bangladesh-born politician who grew up in an apartment overlooking the market. But now, she said, Bangladeshis had found a way to grow and sell them in Palermo, angering the local Mafiosi who see cultivation of the pods as a threat to their traditions and control.