Rootstocks influence yield performance of navel orange trees after drastic pruning

ABSTRACT Drastic pruning is an alternative control recommended in orchards affected by citrus canker (Xanthomonas citri subsp. citri). This study aimed at evaluating the influence of six rootstocks on growth, yield and quality of 'Monte Parnaso'(Citrus sinensis (L.) Osb.) navel oranges, after performing a drastic pruning to eradicate the citrus canker. A complete randomized blocks design, with six treatments and four replicates, was used. The following rootstocks were tested: 'Caipira' sweet orange (C. sinensis (L.) Osb.), 'Volkamer' lemon (C. volkameriana Pasq.), 'Cravo' Rangpur lime (C. limonia Osb.), 'Swingle'citrumelo (C. paradisi Macf. x Poncirus trifoliata (L.) Raf.), 'Sunki' mandarin (C. sunki Hort. ex Tan.) and 'Troyer' citrange (C. sinensis x P. trifoliata). Traits related to plant height, yield and fruit quality were evaluated. The largest cumulative yield was obtained from 'Cravo', 'Volkamer' and 'Sunki'. 'Cravo' and 'Volkamer' induced higher production efficiency, fruits with the highest average weight and the lowest pre-harvest fruit drop. All the evaluated rootstocks produced high quality fruits and similar canopy sizes.