五个杨树品种生长、光合生理及根尖离子流速特性比较分析

Comparative Analysis of Growth,Photosynthetic Physiology and Root Tip Ion Flow Characteristics of Five Poplar Varieties

通过比较不同品种杨树(Populus)的生长、光合生理及根尖离子流速特性差异,为速生适应性强品种的早期选育提供参考。以渤丰3号杨(P.×euramericana‘Bofeng 3’)、渤丰1号杨(P.×euramericana‘Bofeng 1’)、西雄1号杨(P.×euramericana‘Xixiong 1’)、中雄7号杨(P.×euramericana‘Zhongxiong 7’)和中雄4号杨(P.deltoides×P.suaveolens cl.‘Zhongxiong 4’)5个杨树品种1年生苗为研究对象,于正常培养条件下的试验开始和试验结束(30 d)时分别测定株高、地径等生长指标,并于10、20、30 d时分别测定幼苗的叶片数量、单叶面积、叶长、叶宽、瞬时净光合速率(P_(n))、胞间CO_(2)摩尔浓度(C_(i))、气孔导度(G_(s))、蒸腾速率(T_(r))、叶绿素相对含量以及根尖K^(+)、Ca^(2+)、H^(+)流速等指标,经过30 d的正常管理,5个品种的株高生长量之间的差异达到显著水平,由高到低依次为中雄4号杨、西雄1号杨、渤丰3号杨、中雄7号杨、渤丰1号杨;其中光合特性指标和蒸腾速率渤丰1号杨均表现为最大,中雄4号杨均表现为最小,但是中雄4号杨的单叶面积((57.49±2.37)cm^(2))、总叶面积((1721.10±28.59)cm^(2))、单株净光合速率((17863.10±910.21)μmol·m-2·s-1)和水分利用率((3.15±0.06)μmol·mmol^(-1))均表现为最大,且K^(+)外排流速最慢,为(62.68±0.45)pmol·cm^(-2)·g^(-1),Ca^(2+)内流流速最快,为(-74.24±1.29)pmol·cm^(-2)·g^(-1),而渤丰1号的单株净光合速率((8539.70±164.64)μmol·m-2·s-1)和水分利用率((2.64±0.07)μmol·mmol^(-1))最小,且K^(+)外排流速((130.81±1.71)pmol·cm^(-2)·g^(-1))最快,Ca^(2+)内流流速((-34.43±0.84)pmol·cm^(-2)·g^(-1))最慢。综上所述,5个杨树品种中,中雄4号杨总叶面积、单株净光合速率、水分利用率最高,蒸腾速率最小,根尖K^(+)外排流速最慢,Ca^(2+)内流流速最快,植物体内K^(+)、Ca^(2+)离子含量最多,H^(+)最活跃,株高生长表现最好,可能具有潜在的较强环境适应能力,适宜种植的范围更广。

To provide reference for early selection of fast-growing and adaptable varieties,the difference in growth,photosynthetic physiology,and root tip ion flux were analyzed among in five poplar varieties.The annual seedlings of Populus×euramericana‘Bofeng 3’,P.×euramericana‘Bofeng 1’,P.×euramericana‘Xixiong 1’,P.×euramericana‘Zhongxiong 7’,and P.deltoides×P.suaveolens cl.‘Zhongxiong 4’were selected as materials.Growth indexes including plant height and ground diameter were measured at 0 and 30 days under normal culture conditions,respectively.Leaf number,single leaf area,leaf length,leaf width,photosynthetic parameters including P_(n),C_(i),G_(s),T_(r),SPAD and K^(+),Ca^(2+),H^(+)ion flux of roots were measured at 10,20 and 30 days,respectively.Under 30 days normal management,There were significant differences in plant height growth among the five varieties,from high to low,it was‘Zhongxiong 4’,‘Xixiong 1’,‘Bofeng 3’,‘Zhongxiong 7’and‘Bofeng 1’.Among them,the photosynthetic characteristics and transpiration rate of‘Bofeng 1’were the largest,and those of‘Zhongxiong 4’were the smallest.However,the single leaf area((57.49±2.37)cm^(2)),total leaf area((1721.10±28.59)cm^(2)),net photosynthetic rate((17863.10±910.21)μmol·m-2·s-1)and water utilization rate((3.15±0.06)μmol·mmol^(-1))of‘Zhongxiong 4’were significantly decreased.were the largest.The efflux velocity of K^(+)was the slowest((62.68±0.45)pmol·cm^(-2)·g^(-1)),and the influx velocity of Ca^(2+)was the fastest((-74.24±1.29)pmol·cm^(-2)·g^(-1)).The net photosynthetic rate((8539.70±164.64)μmol·m-2·s-1)and water utilization rate((2.64±0.07)μmol·mmol^(-1))of‘Bofeng 1’were the lowest,and the outflow velocity of K^(+)was(130.81±1.71)pmol·cm^(-2)·g^(-1).The Ca^(2+)influx velocity((-34.43±0.84)pmol·cm^(-2)·g^(-1))was the slowest.In summary,among the five varieties,‘Zhongxiong 4’might have potential strong environmental adaptability,with the highest total leaf area,Pn and WUE,the lowest Tr,the smallest K^(+)efflux,largest Ca^(2+)influx of and most active H^(+)of root tip,and best plant height growth performance,which might be suitable for planting a wider range.