Abstract

The effect of grafting technique on plant growth of tomato plants (Lycopersicon esculentum L. cv. Despina) cultivated under salinity stress, either self-rooted (P7) or grafted on to themselves (P6) and five different rootstocks (P1, P2, P3, P4 and P5) was examined. Plants were grown both indoors (heated glasshouse) and outdoors, whereas salinity stress was simulated by applying three levels of salinity [Contol (0.69 mS/cm), 3 and 6 mS/cm) on growth medium. The results of the study showed that grafted plants formed more fruit in total and had a higher total yield than self-rooted plants at the level of 6 mS/cm when grown indoors, whereas mean fruit weight was higher for P2, P5 and P6 combinations. For outdoor cultivation, scion × P1 and P2 combinations were superior to others at the level of 6 mS/cm, regarding total number of fruit and total yield, whereas mean fruit weight was higher for P5 combination. In conclusion, implementing grafting technique on tomato plants results in the formation of more internodes and therefore flowers, especially, for outdoor cultivation, whereas significant effects were observed on both total number and total weight of fruit for indoor cultivation. In addition, rootstock × scion combination has a significant effect on plant growth and yield and could be used as a useful means in order to alleviate problems that arise from salinity stress due to either lack of water or high salinity of irrigation water.

Key words: Lycopersicon esculentum L., grafting, salinity stress, rootstock, scion.