Comprehensive performance of Orah grafted on Carrizo Citrange rootstock in southern area of Guangxi

【Objective】To study the effects of Carrizo Citrange rootstock on tree body and fruit quality of Orah, in order to provide theoretical basis for screening suitable rootstocks of Orah in southern Guangxi.【Method】A long term experiment was conducted in Wuming District，Nanning，Guangxi to study fruit quality of Orah grafted on Carrizo Citrange rootstock for 3 consecutive years（2018-2020）. Orah grafted on Citrus junos Sieb. ex Tanaka，Poncirus trifoliate Raf and tangerine rootstocks were used as controls to analyze tree body indexes（rootstock trunk circumference，scion trunk circumference，trunk circumference difference，tree height and fruit number）and fruit quality indexes（single fruit weight， fruit transverse diameter，fruit longitudinal diameter，fruit shape index，pericarp thickness，edible rate，vitamin C，soluble solids，citric acid，total sugar，and sugar-acid ratio）.【Result】According to data collected in 3 years, Orah grafted on Carrizo Citrange performed better in single fruit weight，fruit number and some quality indexes. The average fruit number in the 3 years was 299，single fruit weight was 143.07 g，vitamin C content was 19.92 mg/100 mL，soluble solids content was 12.51%，citric acid content was 0.584%，total sugar content was 12.46%，and the sugar-acid ratio was 21.42. Compared with the one grafted on P. trifoliate Raf rootstock，Orah grafted on Carrizo Citrange rootstock showed advantages such as stronger growth vigor and larger fruit number，but the difference was not significant compared with that on C. junos Sieb.ex Tanaka rootstock（P>0.05，the same below）. In terms of single fruit weight，Orah grafted on Carrizo Citrange rootstock showed nonobvious downward trend and stable production compared with that on C. junos Sieb.ex Tanaka rootstock. Fruit quality of Orah grafted on Carrizo Citrange rootstock was generally lower than that on P. trifoliate Raf rootstock，but quality difference was not significant after entering high-yield period. Compared with Orah grafted on other 3 rootstocks，Orah grafted on tangerine rootstock was performed rather poorly，as fruit number was less and fruit quality indexes were unsatisfactory. Average fruit number for the 3 years was 185.【Conclusion】Orah grafted on Carrizo Citrange rootstock has a better comprehensive performance in southern area of Guangxi，so Carrizo Citrange rootstock can be considered as a suitable rootstock for Orah in southern area of Guangxi; but Carrizo Citrange rootstock is not suitable to be planted in plots with severe zinc deficiency，and when using Carrizo Citrange rootstock in production，tree vigor should be controlled，tree should be pruned regularly and not be planted densely.