不同间作模式下油用牡丹‘凤丹’光合特性及其与环境因子的关系

Photosynthetic characteristics of oil peony Paeonia ostii under different intercropping patterns and their relationships with environmental factors

为探究油用牡丹主要栽培种‘凤丹’的高效栽培模式,提高土地和光能利用效率,以‘凤丹’单作为对照,比较了‘凤丹’与木瓜、香椿、核桃等经济林木间作模式下的小气候,分析了4种模式下‘凤丹’的光合特性、净光合速率(Pn)与主要生理生态因子的关系以及叶绿素含量和荧光参数的差异。结果表明:6月,4种模式下的小气候具有显著差异;单作和与木瓜间作模式下的‘凤丹’Pn日变化曲线呈明显的双峰型,而与香椿和核桃间作的模式呈单峰型;与核桃间作模式下的Pn的日均值最高,而与木瓜间作模式下的最小;与木瓜间作模式下气孔导度(G_s)的日均值最低;与香椿间作模式下的G_s和蒸腾速率(T_r)日均值均最高,而该模式下的水分利用效率(WUE)最低。相关性分析及多元逐步回归分析表明,不同间作模式中影响‘凤丹’Pn的因子各不相同。同时,间作模式也不同程度地提高了‘凤丹’叶片叶绿素的含量、F_m、F_v/F_m、Φ_(PSⅡ)、ETR、NPQ等。间作模式,尤其是与香椿和核桃间作模式,在保证油用牡丹正常的光合生产的同时,提高了土地和空间的利用效率,增加了单位土地上的生物产量,具有一定的推广价值。

To explore the efficient cultivation of Paeonia ostii,a main cultivar of oil peony,and improve the efficiency of land and light utilization,we measured the microclimate of P. ostii monoculture（ CK） and its intercropping systems with Carica papaya,Toona sinensis,and Juglans regia respectively,and analyzed the photosynthetic characteristics（ Pn） of P. ostii,the relationship between Pnand main eco-physiological factors,and differences among chlorophyll content and fluorescence parameters under the four cropping systems. The results showed that there were significant differences of microclimate among the four cropping patterns in June. Bimodal curves were presented in monoculture and P. ostii-C. papaya intercropping system,while unimodal curves were presented in P. ostii-T. sinensis and P. ostii-J. regia intercropping systems. The highest daily mean value of Pnwas observed in P. ostii-J. regia intercropping system,while the lowest value was in P. ostii-C. papaya intercropping system. The daily mean value of stomatal conductance（ Gs） in P. ostii-C. papaya intercropping system was the lowest. The daily mean values of Gsand transpiration rate（ Tr） in P. ostii-T. sinensis intercropping system were the highest,while the water use efficiency（ WUE） was the lowest in this system. Results from the correlation analysis and multiple stepwise regression analysis showed that eco-physiological factors affecting Pnvaried among intercropping patterns. Moreover,intercropping patterns also increased the chlorophyll content,Fm,Fv/Fm,Φ（PSⅡ）,ETR and NPQ of P. ostii leaves. Therefore,intercropping patterns,especially P. ostii-T. sinensis and P. ostii-J. regia intercropping,could guarantee normal photosynthetic production of oil peony and improve the utilization efficiency of land and light and increased biomass per unit land area,with generalized value of application.