Claim: Bananas on a fishing boat are unlucky.
Origins: We can’t say how far back this superstition goes, but at least among sport fishermen there exists a belief that bananas on a boat are unlucky.
The sea offers plenty of opportunities for turns of ill luck. Fishing boats run aground or become lost. Mechanical failures result in boats floating helplessly adrift. Crew members become deathly sick from mysterious illnesses. Foul weather sweeps in. Any and all of these have been at various times attributed to bad luck.
While the superstitions involving fishermen and their boats are almost too numerous to mention, one particular entry in that category appears to attach almost solely to those who engage in sport (rather than commercial) fishing.
Bananas are deemed unlucky by recreational fishermen and those catering to that trade. Usually this rumor takes the form of the fish not biting on the day when bananas were discovered onboard, but mechanical breakdowns and other mishaps are also pointed to.
Banana
Some in the fishing charters business extend their distaste for the fruit to include not only banana ingestibles (fresh or dried chips of banana, banana muffins, plus anything banana flavored) but even to items bearing the word “banana” or anything evocative of it, such as Fruit of the Loom underwear, Banana Republic apparel, and Banana Boat sunscreen. (The prohibition against Fruit of the Loom underthings is particularly baffling because that clothier’s logo depicts an apple, leaves, green grapes, currants, and purple grapes, with nary a banana in sight.)
More at
https://www.snopes.com/luck/superstition/bananas.asp