This is an old folk song written in 1882 and popularized by Uncle Dave Macon in the 1930s. It is commonly known in the DMB community as "The Watermelon Song."
As this is a folk song, it has no "official" lyrics. It was commonly taught in grammar schools and at camps in the 20th century, with many lyrical variations later in the century. Most of these variations are to remove some racially insensitive content that was present in the original versions of the song (e.g., the exaggerated African-American dialect used, the stereotype that black people cannot resist watermelon). It is likely that the lyrics Dave sings are the ones he learned as a child in whatever venue.
While most versions typically have more verses than Dave's (and the "apples are sweet" verse is actually a refrain), we do not list his renditions as partials since he always sings it the same way (excepting 3.28.03