Vegetative growth, yield and fruit quality of "Hernandina" clementine (as newly introduced cultivar in Egypt) grafted on Sour orange (the most common rootstock), Cleopatra mandarin, Carrizo citrange and "Swingle" citrumelo were evaluated in a private farm at "Wady El-Mullak" region, Ismailia Governorate during 2004/2005 and 2005/2006 seasons.
"Hernandina" clementine trees budded on Carrizo citrange showed higher vegetative growth parameters (canopy circumference and diameter, tree volume) than those on Sour orange, "Swingle" citrumelo and Cleopatra mandarin rootstocks, except the tree height which was similar to those on other rootstocks (except Sour orange which was significantly lower). The highest affinity was found with Sour orange, followed by Cleopatra mandarin and Carrizo citrange without significant differences among them, while the lowest affinity was found with "Swingle" citrumelo.
Trees on Carrizo citrange produced higher yield than those on Sour orange, Cleopatra mandarin and "Swingle" citrumelo rootstocks. The trees grafted on Carrizo citrange had the highest average yield of the two seasons (29.51%, 24.55% and 13.55% over those on Cleopatra mandarin, Sour orange and "Swingle" citrumelo, respectively). Trees on Cleopatra mandarin showed a significant higher alternate bearing index (24.87%) as compared with those on other rootstocks.
Juice SSC, acidity, SSC/acid ratio and ascorbic acid contents were significantly affected by rootstock. The fruits from trees budded on Carrizo citrange showed the highest SSC, while those budded on Sour orange had the lowest SSC and highest acidity. The lowest maturity index was achieved by fruits from trees grafted on Sour orange as compared with those on the other rootstocks; however, the highest maturity index was clear in fruits from trees on Carrizo citrange and "Swingle" citrumelo rootstocks.
Considering the tree growth rate, scion/stock affinity, yield and fruit quality; Carrizo citrange and Cleopatra mandarin can be considered as the most promising rootstocks for 'Hernandina' clementine under the Egyptian conditions.