Characterizing the impacts of 'generative' rootstocks on growth and development of grafted tomato plants

T. Gong, X. Zhao, J.K. Brecht, J. Colee
Recently, so-called 'generative' rootstocks have been introduced by seed companies. This type of rootstock is supposed to limit excessive vegetative growth and promote steady fruit production throughout the season in grafted tomato production. In contrast, 'vegetative' rootstocks have a tendency to cause excessive vegetative growth in grafted plants, leading to possible delay in onset of flowering and fruit set. Little research-based information is currently available to characterize such effects of generative and vegetative rootstocks on growth and development of grafted tomatoes. In this greenhouse study, eight tomato hybrid rootstocks with different descriptions of their attributes including generative, vegetative, vigorous, and mid vigor, were grafted with two grape tomato scions and two beefsteak tomato scions. Interactions significantly affected plant height, node number, stem diameter, and SPAD at early vegetative stage but did not affect stem diameter and SPAD at a late vegetative stage. Rootstocks had no effect on flowering date of the scion. The interactions of rootstock × scion type and rootstock × scion cultivar significantly affected leaf number, leaf area, and biomass accumulation in reproductive parts, leaf, stem and roots at the vegetative growth stage but not at the transition stage or at the beginning of harvest. For both tomato types, root dry weight and root surface area helped in discriminating different groups, but did not consistently drive the separation between different treatments. A consistent grouping pattern was not found among different scion types.
Gong, T., Zhao, X., Brecht, J.K. and Colee, J. (2021). Characterizing the impacts of 'generative' rootstocks on growth and development of grafted tomato plants. Acta Hortic. 1302, 251-258
DOI: 10.17660/ActaHortic.2021.1302.33
Solanum lycopersicum, scion, vegetative

Acta Horticulturae