## 3 Results
### Effect of Covering Purslane on the Grape Physiochemical Indexes  
During the growing period of grapes, the physiochemical indexes of the 'Cabernet Sauvignon' grapes, including the 100-berry weight, soluble solids (TSS), the titratable acidity (TA), and the pH values, were monitored, and the results were shown in Figure 3. In the year 2018, a noticeable difference in grape physiochemical indexes was observed in the ripening process between the control and covering purslane. In the year 2018, Covering purslane significantly decreased the berry TSS from the second sampling time of verison 5%. The maximum difference in the TSS between the control and covering purslane was 2\({}^{\circ}\)Brix, when the control berries had almost reached the ending of verasion, while covering purslane berries were at mid-veraison stage (at approximately 60% of their color). The grapes of control were harvested when the berry TSS had reached 25.1\({}^{\circ}\)Brix, while at this time the berries covering purslane treatment only reached about 24\({}^{\circ}\)Brix. There was no significant difference between the two treatments in the berry weight and TA at their respective harvest times. The grapes covering purslane had lower berry TSS and pH than the control. The maximum difference between covering purslane and the control in terms of the weight of 100 berries at the third sampling stage was 20.4 g. Although there was a significant difference between the two treatments in pH in the last sampling stage, it was mitigated compared with those in other sampling stages.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Parameters**} & \multicolumn{2}{c}{**Treatments**} & \multirow{2}{*}{**Sig.**} \\ \cline{2-3} \cline{5-5}  & **CK** & & **CP** \\ \hline Total shoot leaf area/meter (m\({}^{2}\)/m) & 12.64 \(\pm\) 0.79 & 9.53 \(\pm\) 1.01 & * \\ Main shoot leaf area/meter (m\({}^{2}\)/m) & 5.27 \(\pm\) 0.17 & 3.84 \(\pm\) 0.75 & * \\ Lateral shoot leaf area/meter (m\({}^{2}\)/m) & 7.37 \(\pm\) 0.80 & 5.69 \(\pm\) 0.67 & * \\ Yield/meter (kg/m) & 3.44 \(\pm\) 0.18 & 3.42 \(\pm\) 0.29 & ns \\ Leaf area/yield (m\({}^{2}\)/kg) & 3.67 \(\pm\) 0.45 & 2.75 \(\pm\) 0.42 & * \\ Average shoot length (cm) & 126.00 \(\pm\) 9.70 & 117.80 \(\pm\) 7.94 & ns \\ Third internode diameter (mm) & 0.82 \(\pm\) 0.11 & 0.84 \(\pm\) 0.03 & ns \\ Pruning weight/meter (kg/m) & 1.97 \(\pm\) 0.13 & 1.53 \(\pm\) 0.18 & * \\ Yield/pruning weight & 1.84 \(\pm\) 0.15 & 2.75 \(\pm\) 0.19 & * \\ \hline \hline \end{tabular} Values are reported as means \(\pm\) SD of three biological replicates. * indicates there are significant differences between CK and CP (\(p\) \(<\) 0.05, \(t\)-test). ns = not significant.  
\end{table}
Table 2: Vine parameters of clean tillage control (CK) and covering purslane (CP) of ‘Cabernet Sauvignon’ in the year 2019.  
Figure 3: Berry physicochemical parameters of clean tillage (CK) and covering purslane (CP) of ‘Cabernet Sauvignon’ grapes. (**a**) 100-berry weight in 2018; (**b**) 100-berry weight in 2019; (**c**) total soluble solids in 2018; (**d**) total soluble solids in 2019; (**e**) titratable acidity in 2018; (**f**) titratable acidity in 2019; (**g**) pH value in 2018; (**h**) pH value in 2019. * indicates significant differences between the control and covering purslane (\(p\) \(<\) 0.05, \(t\)-test).  
In the year 2019, compared to covering purslane, the berries of clean tillage had higher pH, and the 100-berry weight, TSS and TA had the same trend as those in the year 2018, but were not affected significantly. Combined with the meteorological data, compared to CP, CK had higher temperature and PAR. The moderate-high temperature was conducive to the accumulation of sugar content [42; 43].