Quantitative criteria of watermelon and squash seedlings used as scion and rootstock during grafting

F. Bantis, A. Koukounaras, A. Siomos, G. Menexes, C. Dangitsis, T. Koufakis
Vegetable grafting is commonly practiced worldwide because of its benefits, such as the mitigation of biotic and abiotic disorders and the reduction of the use of agrochemical products. Watermelon is a valuable crop mainly propagated through grafting onto squash rootstock. Important stage of grafting procedure is the choice of high-quality scion and rootstock seedlings to achieve successful healing and fast growth rate. Until now, most of the seedlings' quality parameters have been characterized as qualitative. The aim of the present study was to set critical limits of easily determined parameters (quantitative) of watermelon and squash seedlings produced for the purpose of grafting, in order to classify them into quality categories. Quality categorizing was assisted by experienced personnel and the categories derived were “lowest not acceptable”, “lowest acceptable”, “optimum”, “highest acceptable” and “highest not acceptable” for watermelon, and “lowest acceptable”, “optimum” and “highest acceptable” for squash. Among all shoot and root traits measured, seedling height, stem diameter, fresh and dry weight of shoots and roots, and leaf area proved valuable for the classification of both species into different quality categories. Those parameters contributed to the general appearance of the seedlings, subsequently leading to quality categorization. In addition, cotyledon thickness, cotyledon area, chlorophyll content and color were strong parameters for the classification of watermelon but weak for squash seedlings. The objective quality categories could assist nurseries and growers to produce grafted watermelon seedlings of high-quality.
Bantis, F., Koukounaras, A., Siomos, A., Menexes, G., Dangitsis, C. and Koufakis, T. (2020). Quantitative criteria of watermelon and squash seedlings used as scion and rootstock during grafting. Acta Hortic. 1294, 155-162
DOI: 10.17660/ActaHortic.2020.1294.20
Citrullus lanatus, Cucurbita moschata, nursery, optimal production, marketable seedlings, quality indicators

Acta Horticulturae