What was the strongest candidate for the original tree of knowledge of good and evil in the seventeenth century?

"Temptation", from a German version of the Vita of Adam & Eve. 

Marina Warner in the article "Bananas" (1995) answers:

In the seventeenth century, when savants were as keen on gardening as on the Bible, the general opinion of herbalists and botanists and connoisseurs of simples was that the banana was the strongest candidate for the original tree of knowledge of good and evil. (The palm was preferred for the Tree of Life.) Such books aren't always reliable guides -- the 'vegetable lamb', which grew on a stalk in Scythia, also makes an appearance in them as part of God's flora. Though nobody put themselves wholeheartedly behind the banana as the fruit whereof Adam did eat, Linnaeus believed in the story enough to give the tree the name Musa paradisica. (335)