Grapevines in cold regions are prone to frost damage in winter. Due to its adverse effects on soil structure, plant damage, high operational costs, and limited mechanization feasibility, buried soil overwintering has been gradually replaced by no-burial overwintering techniques, which are now the primary focus for mitigating frost damage in wine grapes. While current research focuses on the selection of thermal insulation materials, less attention has been paid to the insulation mechanism of covering materials and covering methods. In this study, we investigated the insulation performance of two covering materials (tarpaulin and insulation blanket) combined with six height treatments (5–30 cm) to analyze the effect of insulation space volume on no-buried-soil overwintering. The results show that the thermal insulation performance of the insulation blanket is significantly better than that of the tarpaulin. The 5 cm height treatment under the tarpaulin cover and the 25 cm height treatment under the insulation blanket cover exhibited the best thermal insulation performance. Using a neural network machine learning approach, we constructed a model related to the height of the insulation material and facilitate the model’s accurate predictions, in which tarpaulin R²_branches = 0.92, R²_{20 cm} = 0.99, and R²_{40 cm} = 0.99 and insulation blanket R²_branches = 0.89, R²_{20 cm} = 0.98, and R²_{40 cm} = 0.99. The model predicted optimal insulation heights of 6 cm for the tarpaulin and 22 cm for the insulation blanket. Factors like solar radiation within the insulation space, ground radiation, airflow, and material thermal conductivity affect the optimal insulation height for different materials. This study used a neural network model to predict the optimal insulation heights for different materials, providing systematic theoretical guidance for the overwintering cultivation of wine grapes and aiding the safe development of the wine grape industry in cold regions.

Climate fluctuations due to global warming significantly impact the wine grape industry. This study introduces the Standardized Temperature Adaptation Index (STAI), which is specifically designed to isolate temperature trends and quantify the effects of temperature fluctuations on low-temperature stress affecting Cabernet Sauvignon branches and yields in the wine grape production regions of Xinjiang. A low-temperature fluctuation experiment was conducted on Cabernet Sauvignon branches to simulate the temperature conditions and fluctuations experienced by wine grapes during the overwintering period. The treated branches then underwent recovery growth experiments, during which key physiological stress parameters were measured to assess the impact of temperature fluctuations on grape growth and development during overwintering. The results indicated that under identical low-temperature conditions, increased temperature fluctuations led to a 62% reduction in the budding rate of Cabernet Sauvignon branches, a 6% increase in relative conductivity, and elevated levels of proline, malondialdehyde, and soluble proteins. Additionally, the activities of superoxide dismutase, peroxidase, and catalase initially rose and then declined, indicating that temperature fluctuations intensified low-temperature stress. Data analysis from four wine grape production regions in Xinjiang between 2000 and 2020 revealed that temperature fluctuations corresponded with the peaks and troughs of yield fitting curves, demonstrating a negative correlation. As temperature fluctuations increased, yields decreased. The STAI introduced in this study is a straightforward, standardized measure that accurately reflects the effects of temperature fluctuations on grapes and is a valuable tool for future research on temperature variability and its impacts.

Overwintering frost damage is a major challenge for the wine grape industry in northern China. This study investigates overwintering treatments to improve survival rates and mitigate frost damage in the wine grape production area of the northern foothills of the Tianshan Mountains. Seven overwintering treatments were tested: soil-covered striped cloth, striped cloth, sandwiched striped cloth, thickened striped cloth, double-layered striped cloth, heat-insulating striped cloth, and heat-insulating sandwich striped cloth. Temperature and humidity were continuously monitored during the overwintering period, both aboveground and at depths of 20 and 40 cm underground. By analyzing temperature trends, the duration of low temperatures, and temperature fluctuations, comprehensive overwintering indices were derived through principal component analysis to assess heat retention, moisture preservation, and the impact on grapevine survival. The results showed that the sandwiched striped cloth treatment provided the best insulation, with a 4.4 °C higher minimum daily temperature and a 356% increase in overwintering indices compared to striped cloth alone. The double-layer striped cloth treatment also improved safety, with a 130% increase in overwintering indices. Other treatments, including the soil-covered and the heat-insulating striped cloth, showed reduced performance. The sandwiched striped cloth and double-layer striped cloth treatments are recommended for northern China’s wine grape regions, with further research needed to evaluate their economic viability.