“…Yang et al (2011b) have reported that citrus fruit ripening is associated with the accumulation of primary metabolites, and the levels of sugars and organic acids determine the quality and taste of citrus fruits (Tietel et al, 2011;Chen et al, 2012). Furthermore, it has been evidenced that sugars (mainly glucose and fructose) and organic acids (mainly citric acid and malic acid) are markedly changed during sweet orange ripening (Wu et al, 2014;Yu et al, 2012), and the regulatory mechanism has been investigated increasingly with omics-based approaches, such as transcriptomics (Yu et al, 2012), proteomics (Wu et al, 2014), and metabolomics (Yang et al, 2011b). Although these studies have presented massive data which enlarge the information related to citrus fruit ripening at molecular and metabolic levels, the regulatory mechanism is still poorly understood.…”