Maturation of early-ripening mandarin as affected by scion and rootstock cultivars in western Santa Catarina, Brazil

ABSTRACT In Santa Catarina, Brazil, ‘Satsuma Okitsu’ and the ‘common mandarin' (Citrus deliciosa Ten.) are the widely known mandarin varieties harvested earlier than 'Ponkan'. This study analyzed and compared the maturation evolution of early maturing mandarins in two rootstocks. The experiment had as treatments combinations of the scion cultivars SCS458 Osvino, Clemenules, Satsuma Okitsu and Mexirica do Rio IAC and the rootstocks ‘Swingle’ and ‘IAC 387 Carrizo’. Fruit were sampled during ripening to evaluate soluble solids (SS), total acidity (TA), ratio (SS/TA), juice content and skin color (CIE Lab parameters and color index - CI). Treatments were compared by analysis of variance and linear and nonlinear modeling. Scions significantly affected the evaluated variables, but no rootstock effect was found. ‘SCS458 Osvino’ showed earlier ratio and, mainly, CI, but its juice content was low in part of the period. ‘Satsuma Okitsu’ and ‘Clemenules’ presented, early, higher CI and ratio than ‘Mexirica do Rio IAC’. In conclusion, the cultivars SCS458 Osvino, Satsuma Okitsu and Clemenules are more precocious in maturation compared to ‘Mexirica do Rio IAC’, and the first is the most precocious in peel maturation.

摘要 在巴西圣卡塔琳娜州，‘萨摩津久（Satsuma Okitsu）’与‘普通宽皮柑橘（Citrus deliciosa Ten.）’是采收期早于‘椪柑（Ponkan）’的知名宽皮柑橘品种。本研究对两种砧木上栽培的早熟宽皮柑橘的成熟进程开展分析与比较。本试验以接穗品种组合（SCS458奥斯维诺、克莱门露、萨摩津久、里约梅克西卡IAC）与砧木组合（斯温格尔、IAC 387卡里佐）作为处理组。在果实成熟阶段采样，以评估可溶性固形物（SS）、总酸（TA）、固酸比（SS/TA）、出汁率及果皮色泽（CIE Lab参数与色泽指数CI）。采用方差分析及线性、非线性建模对各处理组进行比较。结果显示，接穗品种对所有评估变量均存在显著影响，但未检测到砧木效应。其中，SCS458奥斯维诺的固酸比及（主要为）果皮色泽指数达标更早，但在部分采样时段其出汁率偏低。萨摩津久与克莱门露在成熟初期的果皮色泽指数及固酸比均高于里约梅克西卡IAC。综上，相较于‘里约梅克西卡IAC（Mexirica do Rio IAC）’，SCS458奥斯维诺、萨摩津久及克莱门露的成熟进程更早，且SCS458奥斯维诺的果皮成熟进程最为提前。