ISSN: 2329-9029
Hanana M, Hamrouni L, Hamed KB and Abdelly C
In order to better understand and elucidate the influence of rootstock/scion interactions under salinity constraint, three grafting combinations have been used: Superior Seedless/110R, Muscat d’Italie/SO4 and Syrah/1103 Paulsen. Superior Seedless/110R combination behaves and displays the same results as ungrafted Superior Seedless variety under both control and stress conditions. On the other hand, since the sensitive rootstock SO4 could improve the behavior of Muscat d’Italie variety against salinity, it highlights the beneficial effect of this combination even the two genotypes are not really tolerant. This gain of performance at both vigor and salinity tolerance levels would result from hybrid vigor. Likewise, even the rootstock 1103P is moderately sensitive, it reaches to improve the behavior of Syrah which is a very sensitive variety. Comparative analysis of the different combinations showed that rootstocks do not behave the same in cases they are used individually or in combination with scion. Indeed, the more or less sensitive rootstocks SO4 and 1103P (taken individually) behave better at the salinity tolerance level since combined with their respective scions. Moreover, varieties tested individually display a different pattern when used with a rootstock. Generally, they behave better (Muscat d’Italie and Syrah cases) or at least stay unchanged (Superior Seedless case) against salinity when they are grafted. The displayed behaviors among the different combinations reveal the existence of interactions between genotypes of rootstock and scion, and that not only rootstock dictates the global phenotype. These interactions enhance and improve generally the phenotype of the grafting combination. With a sensitive rootstock (whatever scion is, tolerant or sensitive), we always obtain a gain of performance which is more pronunciated with sensitive rootstocks.