Comparison of vegetative growth, fruit quality and plant hormone content of 'Ruby Roman' grapevines grafted on diploid and tetraploid rootstocks
The rootstock may affect the scion growth by influencing its water potential, nutrient status, vigor, stress tolerance, or by interactions between rootstock and scion cultivars, leading to changes in fruit quality. To study this statement, 'Ruby Roman' grapevine was grafted on two different rootstocks, 'Kober 5BB' ['5BB(2x)'] (a semi-dwarf rootstock) and 'Hybrid Franc' ['HF(2x)'] (a vigorous rootstock), and their colchicine-induced autotetraploid rootstocks ['5BB(4x)' and 'HF(4x)']. We found that '5BB(4x)' rootstock could decrease the vegetative growth of the 'Ruby-Roman' grapevine, consequently enhancing the skin coloration and sugar content of the berries. To observe the physiological changes between the diploid and the corresponding tetraploid rootstocks, we measured the endogenous plant hormone content, including abscisic acid (ABA), indole-3-acetic acid (IAA), and trans-zeatin (tZ) in tissues of shoot apex, root, and berry skin. On veraison, the ABA content in the '5BB(4x)' berries was the highest among the four types of grafted grapevines, and the IAA and tZ content in these berries tended to be higher as well. However, in the vegetative tissues (shoot apex and roots), the ABA content in the two types of '5BB' grapevine was lower than that in the two types of 'HF' grapevine. In contrast, the IAA and tZ content in the two types of '5BB' grapevine were higher than those in the two types of 'HF' grapevine.
Gao-Takai, M., Shinmura, A., Nito, H. and Katayama-Ikegami, A. (2018). Comparison of vegetative growth, fruit quality and plant hormone content of 'Ruby Roman' grapevines grafted on diploid and tetraploid rootstocks. Acta Hortic. 1208, 207-214
ABA content, red table grape, skin coloration, tree vigor, Vitis labruscana