PRELIMINARY DATA ON INFLUENCE OF SIX CITRUS ROOTSTOCKS ON FRUIT QUALITY OF 'LANE LATE' NAVEL ORANGE

Seven-year-old trees of ‘Lane Late’ grafted on three new citrus rootstocks: ‘Forner-Alcaide n°5’ (‘FA5’), ‘Forner Alcaide n°13’ (‘FA13’) and ‘Forner-Alcaide n°41’ (‘FA41’) (hybrids of ‘Cleopatra’ mandarin × Poncirus trifoliate), and three traditional rootstocks: ‘Carrizo’ citrange (Citrus sinensis × Poncirus trifoliate), ‘Alemow’ (Citrus macrophylla) and ‘Cleopatra’ mandarin (Citrus reshni), cultivated in Andalusia (Spain), were evaluated in the season 2010-2011. They were characterized as their effects on fruit appearance, taste and nutritional compounds. ‘FA5’ and ‘Cleopatra’ madarin maintained fruit quality on the tree for longer time, indicating that they are the most suitable for late harvested cultivars such as ‘Lane Late’. ‘Alemow’ and ‘Carrizo’ citrange showed a faster loss of organoleptic quality due to their lower acidity of the juice. ‘Alemow’ produced larger fruits than ‘Cleopatra’ mandarin and ‘FA13’, although it also produced the lowest juice content and the poorest organoleptic quality. In relation to the remaining quality parameters, ‘Alemow’ and ‘Carrizo’ citrange had the lowest values in fruit firmness, total polyphenols content and antioxidant activity. ‘Cleopatra’ mandarin, ‘FA13’ and ‘FA5’ had the highest antioxidant activity, while ‘FA13’ showed the highest fruit firmness, similar to ‘FA41’ and ‘FA5’.