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【Objective】The present paper aimed to explore the physiological mechanism of kiwifruit pulp colour difference, so as to provide a reference for kiwifruit pulp colour directional breeding. 【Method】Six main kiwifruit varieties in Sichuan province were used as tested materials, the representative periods of fruit development were selected, and the contents of soluble solids, dry matter, total acid, Vc, soluble protein, soluble starch, total phenols, flavonoids and main pigments, as well as the scavenging rates of ABTS free radical, DPPH free radical and hydroxyl free radical were tested, meanwhile the changes of main physiological indexes and their correlation with pulp colour were studied. 【Result】The changes of main physiological indexes of different varieties in fruit development period basically tended to be the same, ‘Hongshi 2’ and ‘Jinshi 1’ maintained high contents of total phenol, Vc and total acid during the whole fruit development period and were significantly higher than the other four varieties in DPPH, ABTS and hydroxyl radical scavenging capacity. In the early stage of fruit harvest, the dry matter content of ‘Hongyang’ was significantly higher than that of the other five varieties, the acid content was the lowest, and the soluble protein content of ‘Cuiyu’ was the highest. It was shown in the results of the analysis on the correlation between physiological index and pigment content that the flavonoid content was significantly or extremely significantly positively-correlated with the pigment content in kiwifruits of different varieties, the hydroxyl radical scavenging rate, vitamin C content and titratable acid content were significantly or extremely significantly negatively-correlated with the pigment content in kiwifruits of several varieties, and the scavenging rates of DPPH and ABTS free radicals, as well as the contents of dry matter, total soluble solid, soluble starch and soluble protein were not consistently correlated with the pigment content in kiwifruits of different varieties. 【Conclusion】There is a significant correlation between the color difference of kiwifruit pulp and some physiological indexes. When breeding, the parent configuration combination matching the target characters can be selected through the test of physiological indexes related to the color of parent pulp. [ABSTRACT FROM AUTHOR]