Abstract:

The flower bud stage is an important phenological stage marking the onset of fruit development of grapevines, and its interannual variation directly affects fruit quality and yield. This paper adopted phenological data of the Thompson Seedless grape (the dominant cultivar in Turpan City, Xinjiang) during its flower bud stage (from budburst to the end of flowering) from 1991 to 2024 and matching meteorological observation data. Climate trend rate analysis, correlation test and stepwise regression were applied to investigate the effects of climatic factors and last spring frost on the flower bud stage of the Thompson Seedless grape in extreme arid regions. The results show that under the background of warming and drying climate, the onset dates of all grape phenological stages exhibited advancing trends to varying degrees. The inflorescence stage advanced the most significantly at a rate of 5.02 d·(10 a)^-1 (p<0.01), and the duration of grape flower bud stage exhibited a notable lengthening trend. The date of last spring frost advanced significantly at a rate of 6.43 d·(10 a)^-1 (p<0.01). Climate change characteristics during the first decade of the 21st century were most prominent, with the flower bud duration extending by 21.94 d·(10 a)^-1 (p<0.01), and frost damage frequency reaching once every 2 years. Climate warming and drying in extreme arid regions significantly increased the risk of frost damage during the grape flower bud stage. The day-of-year of each grape phenological stage was significantly correlated with variations in meteorological factors (p<0.05), and relative humidity and soil temperature were identified as the dominant ten-day climatic factors influencing grape flower bud phenology. From budburst to inflorescence stage, lower relative humidity and higher soil temperature resulted in earlier phenological development, whereas for the onset of flowering, higher relative humidity was associated with earlier development while lower relative humidity was associated with later development. Clarifying the variation characteristics of grape flower bud phenology and last spring frost in Turpan City can provide scientific guidance for grape cultivation in extreme arid regions.

Key words: grape flower bud stage, phenological characteristics, extreme arid region, climate warming, frost risk

摘要：

植物花芽期是表征植物果实开始生长的重要生育期，其变化会直接影响植物果实品质与产量。本文利用新疆吐鲁番市主栽品种无核白葡萄1991—2024年花芽期（芽开放期至开花末期）物候数据以及对应时段气象观测资料，采用气候倾向率、相关性检验和逐步回归等方法，分析极端干旱区气候因子和终霜冻对无核白葡萄花芽期的影响。结果表明：在气候暖干化背景下，葡萄不同物候期的起始日期均呈不同程度的提前趋势，其中花蕾花序期提前幅度最大，为5.02 d·（10 a）^-1（p<0.01）；葡萄花芽期长度呈显著延长趋势。研究区终霜冻日以6.43 d·（10 a）^-1（p<0.01）的速率显著提前。21世纪最初十年暖干化特征最突出，葡萄花芽期长度以21.94 d·（10 a）^-1（p<0.01）的幅度显著延长，霜冻灾害发生频率达2 a一遇，极端干旱区气候暖干化会显著增大葡萄花芽期冻害风险。葡萄不同物候期日序数与气象因子变化显著相关（p<0.05），影响物候早晚的主导旬气候因子为相对湿度与地温，芽开放期至花蕾花序期表现为相对湿度越小、地温越高，物候越早，开花始期则表现为相对湿度越大，物候期越早。明确吐鲁番市葡萄花芽期物候变化与终霜冻变化特征，能为极端干旱区葡萄生产提供科学指导。

关键词: 葡萄花芽期, 物候特征, 极端干旱区, 气候变暖, 霜冻风险