【摘要】 [目的]为山核桃丰产、科学制定栽培措施提供应用基础依据。[方法]基于对山核桃生物学特性和物候期的观察和对比；使用美国Licor-6400光合作用测定系统直接输出自然光照下叶温、进气CO₂浓度、叶室CO₂浓度、细胞间隙CO₂浓度、光合速率、蒸腾速率、气孔导度等指标的数据，从而确立山核桃净光合速率日变化规律。[结果]山核桃果实动态生长表现为单果质量总体不断增长，呈“S”型生长曲线，初果后20 d内增长极慢，此后的40 d缓慢增长，7月上旬果实开始快速生长，并维持30 d以上。影响山核桃光合速率日变化的因素不仅有光照、CO₂浓度，还有叶片的气孔导度、蒸腾速率、叶温等因素。净光合速率在上午高于下午，有“午休”现象；叶片气孔导度与叶片光合速率的日变化趋势呈正相关关系；胞内CO₂浓度日变化和大气中CO₂浓度日变化与光合速率日变化呈负相关；空气中CO₂浓度在一天内，早晚浓度较高；一天内，蒸腾速率和光合速率的日变化趋势类似，均受到叶片气孔开启的调节作用；一天中随气温、光强的增加，叶温增加，当蒸腾作用受阻时，叶温升高；光合作用后的CO₂浓度降低，此时应及时补充CO₂以保证光合作用，为山核桃的丰产奠定基础。[结论]该研究结果进一步证实了山核桃的喜温特性与光合性能密切相关。提高光合性能，或从品种到栽培措施来改善光合物质的积累是山核桃丰产的基础工作；山核桃的日光合速率有明显光“午休”现象，光合作用呈双峰曲线。更多还原

【Abstract】 [Objective] To provide an application basis for the high yield and scientific formulation of cultivation measures for Carya cathayensis Sarg.[Method] Based on the observation and comparison of biological characteristics and phenological stages of Carya cathayensis Sarg, the daily variation pattern of net photosynthetic rate of Carya cathayensis Sarg has been established by directly outputting data of leaf temperature, entrance CO₂ concentration, leaf chamber CO₂ concentration, intercellular CO₂ concentration, photosynthetic rate, transpiration rate, stomatal conductance and other indexes using the American Licor-6400 photosynthesis measurement system.[Result] The dynamic growth of the fruit on Carya cathayensis Sarg showed an increasing trend of ‘S’ growth curve of single fruit quality. Growth was extremely slow for the first 20 days after fruiting, and slower for the next 40 days. The fruit began to grow rapidly in the first ten days of July, and continued for more than 30 days. Factors affecting diurnal variability of photosynthetic rate in Carya cathayensis Sarg were not only light and CO₂ concentrations, but also stomatal conductance, transpiration rate, leaf temperature, and so on. The net photosynthetic rate in the morning was higher than that in the afternoon, and there was a ‘lunch break’ phenomenon. There was a positive correlation between leaf stomatal conductance and diurnal variability trends in leaf photosynthetic rates. The diurnal variability of intracellular CO₂ concentration and atmospheric CO₂ concentration was negatively correlated with the diurnal variability of photosynthetic rate. The concentration of CO₂ in the air was higher in the morning and evening. Within a day, diurnal variability trends were similar for both transpiration and photosynthetic rates, which were regulated by leaf stomata opening. Over the course of the day, the leaf temperature increased with increasing air temperature and light intensity. When transpiration was blocked, the leaf temperature increased. The concentration of CO₂ drops after photosynthesis, so it should be replenished in time to ensure photosynthesis.[Conclusion] The results of this study further confirm that the temperature-loving properties of Carya cathayensis Sarg were closely related to photosynthetic properties. Improving photosynthetic performance or improving photosynthetic accumulation from variety to culture measures was a fundamental task for high production of Carya cathayensis Sarg. The daily photosynthetic rate of Carya cathayensis Sarg showed obvious light ‘lunch break’ phenomenon, and the photosynthesis showed a double-peak curve.更多还原