Influence of rootstock on postharvest watermelon quality

The cultivation of grafted watermelon has spread to different parts of the world in order to improve production under adverse conditions; however, this technique may alter the quality of the fruit. Therefore, the aim of this work was to evaluate the effect of eight rootstocks, six native Lagenaria siceraria varieties (L43, L46, L48, L50, L54 and L56) and two commercial squash varieties (Super shintosa and TZ 148), in addition to the control plant (without grafting), on the postharvest quality of watermelon variety Tri-X 313. The experimental design was completely randomized with a factorial arrangement and three replicates per treatment. The evaluated variables were fruit weight, firmness, total soluble solids and pulp color. The post-harvest quality of the fruits was not modified by grafting; however, it increased fruit weight by 44 %, except for L50. Pulp firmness was favored 29 % with Super shintosa. The °Brix increased 7 % with L54 and L56. Pulp color was slightly affected with Lagenaria by presenting a lower-intensity red color. The quality of the fruits, during the 14 days of storage, changed in firmness, °Brix and pulp color. The L43, L46 and L48 rootstocks were identified as the most promising to reduce weight loss, retain firmness and maintain pulp color. On the other hand, L54 and L56 promoted °Brix content, but slightly diminished pulp color.