【目的】文冠果(Xanthoceras sorbifolium Bunge)具有喜光、耐寒、耐旱、不耐涝等特性,在中国天然分布于东北、西北、华北等地区,是造林绿化、防风固沙、退耕还林的首选树种。研究不同分布区多种环境因子对文冠果物候期的综合影响,分析其物候期变异规律,为文冠果资源保护和开发利用提供依据。【方法】以中国6个主要分布区(内蒙古坤都、内蒙古天山、内蒙古乌丹、河北省承德、河北省蔚县、河南省陕县)实生群体的文冠果植株为对象,于2016年在各样地内选择长势相对一致的样株30株,采取定株定枝方法,对文冠果的初花期、叶芽萌动期、盛花期、末花期、展叶期、果速生期、果熟期、落果期和落叶期等共9个物候期进行系统观测。采用相关性分析、回归分析等方法,明确影响文冠果各物候期的主导环境因子及其作用规律。【结果】不同分布区文冠果物候期存在明显差异,其中,盛花期差异最大(42 d),果速生期差异最小(29 d)。河南陕县群体的文冠果大部分物候期出现最早,但落叶期最晚,总生长期最长(221 d);内蒙古坤都群体的文冠果落叶期最早,其他物候期出现最晚,总生长期最短(146 d)。大部分物候期与经纬度、年日照时间正相关,与其他环境因子负相关。年均气温是影响初花期、盛花期、末花期、展叶期、果速生期、落叶期和总生长期的主要因子;影响叶芽萌发期和落果期的主要因子是无霜期;影响果熟期的主要因子是年日照时间;影响总花期的主要因子是绝对最高温。【结论】文冠果物候期呈现明显的地理变异规律,环境因子对其物候变化影响显著。随着经纬度升高,气温逐渐下降,春季达到生长临界温度越晚,文冠果开花、展叶、结实越晚,并且秋季植株停止生长和落叶越早,因此其总生长期变短。

【Objective】 Xanthoceras sorbifolium Bunge is a light-loving species and adapts well to low temperatures and drought conditions, but it is susceptible to waterlogging. This species is naturally distributed in northeastern, northwestern and northern China. It is an ideal species for afforestation, wind and sand fixation, and conversion of cropland to forest. This study aimed to clarify the comprehensive effects of various environmental factors in different distribution areas on the phenophases ofX. sorbifolium Bunge and analyze the related variation pattern to provide a scientific basis for resource protection and development of this species. 【Method】 Six X. sorbifolium Bunge seedling populations from its main distribution areas, including Kundu, Tianshan and Wudan in Inner Mongolia Autonomons Region, Chengde and Yuxian in Hebei Province, and Shaanxian in Henan Province, were considered for this study. In 2016, 30 individual plants with consistent growth vigor were selected from each seedling population to systematically observe nine phenophases, including the early flowering stage, leaf bud germination stage, full flowering stage, late flowering stage, leaf expansion stage, fruit fast-growing stage, fruit maturing stage, fruit dropping stage and deciduous stage. Correlation and regression analyses were performed to reveal the dominant environmental factors that affected phenophase and function rules.【Result】 Significant differences were observed in the phenophases among the plants from the different distribution areas. The maximum and minimum differences were observed in the full flowering stage (42 days) and fruit fast-growing stage (29 days), respectively. Most of the phenophases of the plants from the Shaanxian population occurred earlier than those of the plants from the other populations, although the deciduous stage was the longest in the Shaanxian population, which led to the longest total growth period (221 days). In the Kundu population, the deciduous stage occurred early and the other phenophases occurred late; as a result, this population had the shortest total growth period (146 days). Most of the phenophases were positively correlated with longitude, latitude, and annual sunshine hours and negatively correlated with altitude, annual average temperature, absolutely highest temperature, absolutely lowest temperature, ≥10 ℃ annual accumulated temperature, annual rainfall, annual evaporation and frostless period. Annual average temperature was the main factor that influenced the early flowering stage, full flowering stage, late flowering stage, leaf expansion stage, fruit fast-growing stage, deciduous stage and total growth period. Frost-free period had a significant effect on the leaf bud germination stage and fruit dropping stage. The fruit maturing stage was mainly affected by the annual sunshine hours. The absolute maximum temperature was the main factor that affected the total flowering period.【Conclusion】 There is an obvious geographical variation pattern in the phenophases ofX. sorbifolium Bunge, and environmental factors significantly affect these phenophases. Higher latitude and longitude decrease the temperature and postpone the critical growth period of X. sorbifolium Bunge. Correspondingly, its florescence, bud bursting, and fruiting stage are postponed and the species stops growing and defoliates earlier in autumn. As a result, the total growth period ofX. sorbifolium is shortened.