性别和发育阶段对绒毛白蜡光合特征及叶功能性状的影响

雌雄异株植物资源分配模式上往往表现出显著的性别二态性，但在叶片光合及功能性状上是否有差异目前仍未有定论，且与发育阶段的关系尚不明确。阐明上述问题，能够进一步了解雌雄异株植物的生理生态特征，并为理解性别对性二态植物生长发育的影响机制提供理论依据。以雌雄异株绒毛白蜡(Fraxinus velutina Torr.)为研究对象，针对不同发育阶段不同性别植株进行光合特征及叶功能性状测定，采用双因素方差分析了不同发育阶段下雌雄植株光合能力及叶功能性状的性别间差异，采用Pearson检验了雌雄植株各叶功能性状之间的相关性，并采用标准化主轴分析(Standardized major axis regression, SMA)分析不同性别植株净光合速率与叶功能性状的相关性。结果表明性别和发育阶段显著影响植物个体的光合能力和叶功能性状。总体而言，雄树在坐果期和果实成熟期均表现出更强的净光合速率(Pn)、更高的比叶面积(SLA)、叶绿素含量(Chl)和叶氮含量(LNC);而雌树在果实膨大期表现出更强Pn、SLA和Chl。雌雄性别内Pn与SLA、Chl和LNC间均呈显著正相关(P<0.05),雄树的S...

Effects of gender and development stages on photosynthetic characteristics and leaf functional traits of Fraxinus velutina Torr

The resource allocation patterns of dioecious plants often show significant gender dimorphism. but whether there are differences in leaf photosynthetic and leaf functional traits between dioecious plants is still uncertain, as well as the relationship with development stages is not clear. Clarifying the above-mentioned problems can further understand the physiological and ecological characteristics of dioecious plants, and provide a theoretical basis for understanding the influence mechanism of gender effects on the growth and development of sexual dimorphic plants. In our research, the photosynthetic characteristics and leaf functional traits between gender in dioecious species Fraxinus velutina Torr. were measured at three different development stages (Fruit setting stage, Fast-growing stage, and Fruit ripening stage). A two-way ANOVA was used to analyze the gender differences in photosynthetic capacity and leaf functional traits of male and female plants among different development stages. Pearson was used to test the correlation between leaf functional traits of male and female plants, and a standardized major axis regression (SMA) was used to understand the correlation between net photosynthetic rate and leaf functional traits of different gender plants. The results showed that gender and development stages significantly affected the photosynthetic capacity and leaf functional traits in F. velutina Torr. Generally speaking, compared with female trees, male ones showed higher net photosynthetic rate (Pn), specific leaf area (SLA), chlorophyll content (Chl) and leaf nitrogen content (LNC) at fruit setting stage and fruit ripening stage, and lower Pn, SLA, and Chl in the fruit growing stage. There was a significant positive correlation between Pn and SLA, Chl and LNC in male and female (P<0.05), and the slope of SLA vs. Pn was higher in male trees than female trees (P<0.05). The relationship between Chl vs. Pn was not significant between the genders (P>0.05) and the slope of LNC vs. Pn of male trees was higher than that of female trees (P<0.05). The results of SMA model indicated that the light energy utilization efficiency and photosynthetic nitrogen utilization efficiency were higher in male trees than those in female trees, and female trees would use more biomass and nitrogen for non-photosynthetic processes, but no significant differences were found in light absorption rate between genders. The results of this study showed that the life history strategies of male and female individuals of F. velutina Torr. were different, and there existed significant sex dimorphism in photosynthetic traits and leaf functional traits at three different development stages.