Watermelon Foliage and Yield Relationships

Abstract

Watermelon vines and foliage are often damaged or restricted by mechanical operations, diseases, and insects. There is little information to indicate the optimal ratio of plant foliage to fruit. Most watermelon fruits are produced near the plant crown, and thus some farmers believe that extensive foliage is nonessential for fruit production. Experiments have been conducted with watermelon [Citrullus lanatus (cvs. Sangria, Crimson Trio, and Scarlet Trio)] in Oklahoma to determine the relationship between soil surface area covered by foliage (foliar area) and fruit yield. Watermelon plants were planted on 4-m row centers, and were either pruned to allow a foliar area that was 1, 2, 3, or 4 m wide, or were physically confined to the same foliar area by redirecting the branch tips back into the row toward the base of the plant. There was a linear increase in yield as foliar area increased with both `Sangria' and `Scarlet Trio', but not necessarily with `Crimson Trio'. Within a given foliar area, pruning the foliage and confining the foliage to a similar area produced similar effects on fruit yield. A second experiment was conducted to determine the effect on plant yield when the vines were physically moved, as occurred with the confined area treatments. In this study, physically moving the vines did not reduce yield as compared to vines that were not moved.