**3. Data Analysis and Results**

#### *3.1. Effects of High-Ca Treatment on Sugar Content*

As shown in Figure 1a,b, the glucose and fructose content in the fruit pulp exhibited the same increasing trend; after 71 d, the contents in the high-Ca treatment group were significantly lower than those in the CK group, so the accumulation of reducing sugars was inhibited by the high-Ca treatment.

As shown in Figure 1c, the dynamic changes in the sucrose content showed a singlepeak curve, but the peak in the high-Ca treatment group occurred 57 d after anthesis, and the peak in the CK occurred 50–64 d after anthesis. There was no significant difference in the sucrose content between the high-Ca treatment and CK before 50 d after anthesis, yet at 57 d after anthesis, the content in the high-Ca treatment group was significantly higher than that in the CK group. Additionally, at 57 d after anthesis, the content in the high-Ca treatment was significantly lower than that in the CK, so the inhibition of sucrose accumulation in response to the high-Ca treatment occurred at this time.

**Figure 1.** *Cont*.

**Figure 1.** Effects of high-Ca treatment on sugar accumulation and Ca content: (**a**) content of glucose; (**b**) content of fructose; (**c**) content of sucrose; (**d**) content of soluble proportion; (**e**) content of Ca. Note: The symbols with \* in the figure indicate significant differences between the CK and high-Ca treatments for the same data type; otherwise, there was no significant difference. The same scheme applies to the figures below.

As shown in Figure 1d, the dynamic change trend of the soluble sugar content of the high-Ca treatment and CK was different, and the phenomenon of "sugar withdrawal" appeared in the flesh at the mature stage. The difference was that there was no significant change from 43 to 57 d after anthesis, and at 64 d after anthesis, the value in the high-Ca treatment was significantly lower than that in the CK. As a result, the accumulation of soluble sugar was significantly inhibited by high-Ca treatment.

#### *3.2. Ca Content*

It can be seen from Figure 1e that the Ca content of treatment and CK shows a "W" shaped trend of decreasing, rising, decreasing, and rising. There were two troughs, 57 and 71 d after flowering. Treatment was significantly higher than CK at 57 days after flowering; there was no significant difference between treatment and CK on other dates. It shows that pretreatment can increase the Ca content.
