Abstract:

As a geo−authentic medicinal herb in the Yimeng mountain area, honeysuckle (Lonicera japonica Thunb.) exhibits significant economic and ecological value, with its quality and yield being highly sensitive to climatic conditions. Based on meteorological data (1991−2020) from the Pingyi national basic meteorological station, this study developed temperature, water, sunshine hours and comprehensive climate suitability models for the key growth periods of honeysuckle (including sprouting−leaf expansion period, shoot growth period, bud formation period and flower bud enlargement period). Temporal variation characteristics of climate suitability and their correlations with yield were systematically analyzed to identify key determinants governing climatic adaptability of honeysuckle. The findings provided scientific support for addressing geo−authenticity degradation risks under climate change and achieving yield stability and quality improvement. The results were as follows: (1) during 1991–2020, the temperature suitability of the whole growth period for honeysuckle exhibited a significant increasing trend (0.016·10y⁻¹, P<0.05), with the most rapid rise observed during the bud formation period (0.032·10y⁻¹, P<0.01). The flower bud enlargement period demonstrated optimal thermal conditions (0.953±0.045), while frost prevention remained critical during sprouting–leaf expansion period. (2) The water suitability for honeysuckle in the Yimeng mountain area exhibited substantial interannual variability of the whole growth period, with a coefficient of variation (18.9%) significantly higher than that of temperature suitability (5.0%) and sunshine suitability (9.5%). The uneven distribution of precipitation led to suboptimal water suitability in certain years, determining water conditions as the primary limiting factor for honeysuckle production. Crucially, optimized water management during the flower bud enlargement period had been identified as a key determinant for yield stabilization. (3) The sunshine suitability of the whole growth period for honeysuckle in the Yimeng mountain area showed a significant declining trend (−0.030·10y⁻¹, P<0.05), with the most rapid decline occurring during the sprouting−leaf expansion period (−0.077·10y⁻¹, P<0.05), which adversely affected early growth. The flower bud enlargement period exhibited the highest sunshine suitability, promoting photosynthesis and flower bud formation in honeysuckle. (4) The comprehensive climate suitability remained generally stable and exhibited a progressive increase throughout the developmental process. The light, temperature and water conditions during the flower bud enlargement period had been synergistically optimized to support the production of honeysuckle. (5) The meteorological yield of honeysuckle showed a highly significant positive correlation with the comprehensive climate suitability (P<0.001), with the strongest correlation observed during the flower bud enlargement period, followed by the bud formation period. In summary, honeysuckle yield results from the synergistic effects of light, temperature and water conditions. Of these, water availability emerges as the primary limiting factor for yield in Yimeng mountain area, with water suitability during flower bud enlargement period being the key determinant. Secondly, sunshine also has a significant effect on yield. Optimizing water management during the flower bud enlargement period and enhancing comprehensive climate suitability constitute critical measures for improving yield stability in honeysuckle production.

Key words: Yimeng mountain area, Honeysuckle (Lonicera japonica Thunb.), Climate suitability, Yield