摘要
探究大花紫薇新品种紫婵的光合生理特征,为其栽培与推广应用提供理论基础。以2年生紫婵和大花紫薇幼苗为材料,采用Li-6400XT便携式光合仪,测定2个试验植物材料的光合日变化、光响应曲线及叶绿素含量。研究结果表明:(1)紫婵的叶绿素a(Chla)、叶绿素b(Chlb)、类胡萝卜素(Car)含量、叶绿素含量(Chl)以及叶绿素a/b(Chla/Chlb)均显著大于大花紫薇(P<0.05)。(2)紫婵的净光合速率(Pn)日变化呈单峰曲线,峰值出现在10:00,为17.11μmol/(m^(2)·s);气孔导度(G_(s))和蒸腾速率(T_(r))日变化均呈单峰曲线,胞间CO_(2)浓度(C_(i))为早晚高中午低的单谷型,气孔限制值为早晚低中午高的单峰曲线。(3)大花紫薇的净光合速率日变化呈双峰曲线,峰值分别出现在8:00和12:00,分别为14.41μmol/(m^(2)·s)和13.16μmol/(m^(2)·s);气孔导度亦呈双峰曲线,峰值分别出现在8:00和12:00,蒸腾速率日变化呈单峰曲线,峰值出现在10:00左右,胞间CO_(2)浓度为早晚高中午低的单谷型,气孔限制值为早晚低中午高的双峰型曲线。(4)灰色关联分析表明,2种植物材料的Pn与环境因子关联度排序均为PAR>C_(a)>RH。紫婵的Pn与生理因子的关联度排序为T_(r)>G_(s)>T_(a)>C_(i),而大花紫薇为G_(s)>T_(r)>T_(a)>C_(i)。(5)紫婵的光饱和点为2388.729μmol/(m^(2)·s);光补偿点为55.590μmol/(m^(2)·s);大花紫薇的光饱和点为2080.297μmol/(m^(2)·s);光补偿点为29.871μmol/(m^(2)·s),与大花紫薇相比较,紫婵的光饱和点和光补偿点均较高,具有较强的光合同化能力,但对弱光环境适应性较差。紫婵为喜光型树种,适宜栽植在光照充足的环境。
Lagerstroemia speciosa Zichan is a new variety of Lagerstroemia speciosa.In order to provide theoretical basis for its cultivation and promotion application,the physiological characteristics would been explored.The paper used the Li-6400 XT photosynthetic apparatus to determine the light response curves,diurnal variation and chlorophyll of biennale L.speciosa Zichan and L.speciosa sapling.The results showed that:(1)The contents of chlorophyll a(Chla),chlorophyll b(Chlb),carotenoid(Car),chlorophyll content(Chl)and chlorophyll a/b(Chla/Chlb)of L.speciosa Zichan were higher than those of L.speciosa,and there were significant differences in the above indexes.(2)Diurnal change of photosynthetic rate of L.speciosa Zichan displayed a unimodal curve,and the peak appeared at around 10:00 am,which was 17.11μmol/(m^(2)·s);diurnal change of stomatal conductance and transpiration rate showed unimodal curves as well.The diurnal variation of intercellular CO_(2) concentration was high in the morning and evening,low at noon,and the di-urnal variation of stomatal limitation value was low in the morning and evening,high at noon.(3)Diurnal change of photosynthetic rate of L.speciosa displayed a bimodal curve,and the peak appeared at around 8:00 am or 12:00 am,which was 14.41μmol/(m^(2)·s)and 13.16μmol/(m^(2)·s);diurnal change of stomatal conductance showed bimodal curve as well,and the peak appeared at around 8:00 am or 12:00 am.The diurnal variation of transpiration rate showed unimodal curve,and the peak appeared at around 10:00 am.The diurnal variation of intercellular CO_(2) concentration was high in the morning and evening,low at noon,and the diurnal variation of stomatal limitation value was low in the morning and evening,high at noon.(4)Grey relational analysis showed that the order of correlation degree between Pn and environ-mental factors of the two materials was PAR>C_(a)>RH.The order of correlation between Pn and physiological factors was T_(r)>G_(s)>T_(a)>C_(i),while G_(s)>T_(r)>T_(a)>C_(i).(5)The light saturatio
作者
袁汕
林嘉蓓
张恒
奚如春
YUAN Shan;LIN Jiabei;ZHANG Heng;XI Ruchun(College of Forestry and Landscape Architecture,South China Agricultural University,Guangzhou,Guangdong 510642,China;Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm,Guangzhou,Guangdong 510642,China)
出处
《热带作物学报》
CSCD
北大核心
2023年第4期757-765,共9页
Chinese Journal of Tropical Crops
基金
广东省林业科技创新项目(No.2023KJCX002)。
关键词
紫婵
大花紫薇
光合特性
叶绿素含量
Lagerstroemia speciosa Zichan
Lagerstroemia speciosa
photosynthetic characteristics
chlorophyll content
