Rootstock capacity in improving production and quality of triploid watermelon seeds

Abstract

The aim of this study was to evaluate different rootstocks for improving triploid seed production of the dessert watermelon,Citrullus lanatus. This 2-year study was conducted at two locations, in open fields at Antalya and Adana, Turkey, during the 2016 and 2017growing seasons. The tetraploid watermelon line ‘ST 101’ was used as the female parent scion and the diploid line ‘WL 92’ as the maleparent. Both parental lines were grafted onto three different rootstocks to determine the effect of grafting on seed yield and quality of triploidwatermelon. Nun 9075, a Cucurbita interspecific hybrid (Cucurbita maxima × Cucurbita moschata), Argentario (Lagenaria siceraria), andcitron watermelon PI 296341 (Citrullus amarus) were used as rootstocks. Nongrafted ST 101 and WL 92 were also crossed to be used ascontrols. The graft combinations and controls were compared for performance as measured by length, diameter and number of nodesof main stem, total yield, mean fruit weight, fruit length, fruit diameter, seed yield, number of seed per fruit, weight of 1000 seeds, seedgermination and emergence percentage, days to germination and emergence, and seed coat and embryo weight ratio. Nun 9075/ST 101and Argentario/ST 101 graft combinations resulted in longer main stems; increased total yield; heavier, longer, and wider fruits; and higherseed yield and number of seeds per fruit as compared to PI 296341/ST 101 graft combination and the controls in both locations and years.