摘要
【目的】探究外源CaCl_(2)对盐碱胁迫下万寿菊生长和光合特性的影响,为应用CaCl_(2)提高盐碱地上万寿菊栽培效率和产品品质提供理论支撑。【方法】以万寿菊幼苗为试材,设置浇灌清水(CK_(1))、根灌80 mmol/L混合盐碱溶液(CK_(2))和根灌盐碱后叶面喷施4种浓度CaCl_(2)溶液处理(5,10,15,20 mmol/L)进行盆栽试验,观测植株生长表型、叶片光合色素含量、光合气体交换参数和叶绿素荧光参数。【结果】随着盐碱胁迫时间延长,万寿菊植株的株高、茎粗、根系构型和根冠比呈逐渐上升趋势,叶片净光合速率(P_(n))、蒸腾系数(T_(r))、气孔导度(G_(s))、叶绿素总量(Chl_(t))和最大光化学效率(F_(v)/F_(m))等均呈下降趋势,而胞间CO_(2)浓度(C_(i))呈上升趋势,但这些指标在叶面喷施不同浓度CaCl_(2)后变化幅度均有所降低,并均以10 mmol/L CaCl_(2)处理效果最佳。在胁迫第20天时,10 mmol/L CaCl_(2)处理叶片Chl t、P_(n)、T_(r)、G_(s)、F_(v)/F_(m)分别比CK_(2)显著升高46.78%、45.53%、49.51%、49.57%和32.83%,其根冠比和C_(i)则分别显著降低22.60%和30.91%。【结论】叶面喷施10 mmol/L CaCl_(2)可显著减轻盐碱胁迫下万寿菊叶片叶绿素含量降幅,提高PSⅡ的电子传递速率,增强叶片的光合能力,有效改善植株生长。
[Objective]This study aims to explore the effects of exogenous CaCl_(2)on the growth and photosynthetic characteristics of marigold(Tagetes erecta L.)under saline-alkali stress,and to provide theoretical support for the application of CaCl_(2)to improve the cultivation efficiency and product quality of marigold on saline-alkali land.[Methods]Taking marigold seedlings as test materials,pot experiment was carried out to observe the growth phenotype,photosynthetic pigment content,photosynthetic gas exchange parameters,and chlorophyll fluorescence parameters of marigold seedlings by watering(CK_(1)),root irrigation with 80 mmol/L mixed saline-alkali solution(CK_(2)),and root irrigation with saline-alkali followed by foliar spraying with four concentrations of CaCl_(2)solution(5,10,15,20 mmol/L).[Results]With the prolongation of saline-alkali stress,the plant height,stem diameter,root configuration,and root-shoot ra-tio of marigold plants showed a gradual upward trend,and the net photosynthetic rate(P_(n)),transpiration coefficient(T_(r)),stomatal conductance(G_(s)),total chlorophyll content(Chl_(t)),and maximum photo-chemical efficiency(F_(v)/F_(m))of leaves showed a downward trend,while intercellular CO2 concentration(C_(i))showed an upward trend.After spraying different concentrations of CaCl_(2)on the leaves,the change of each index was decreased.There was a concentration effect,and the effect of 10 mmol/L CaCl_(2)treat-ment was the best.On the 20 th day of stress,the Chl t、P_(n)、T_(r)、G_(s)、F_(v)/F_(m)of leaves treated with 10 mmol/L CaCl_(2)were higher than those of CK_(2)by 46.78%,45.53%,49.51%,49.57%,and 32.83%,while the root-shoot ratio and Ci were reduced by 22.60%and 30.91%,respectively.[Conclusion]Spra-ying 10 mmol/L CaCl_(2)on the leaves reduces the decrease of chlorophyll contents in marigold leaves under saline-alkali stress,increases the electron transport rate of PSⅡ,enhances the photosynthetic capacity of leaves,and effectively improves the growth of plants.
作者
王静
蒋倩
陶田田
汪雒璿
王燕
缐旭林
WANG Jing;JIANG Qian;TIAO Tiantian;WANG Luoxuan;WANG Yan;XIAN Xulin(College of Horticulture,Gansu Agricultural University,Lanzhou 730070,China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2024年第9期1345-1354,共10页
Acta Botanica Boreali-Occidentalia Sinica
基金
甘肃省高等学校创新基金项目(2022B-098)。
关键词
外源钙
万寿菊
盐碱胁迫
生长指标
气体交换参数
叶绿素荧光参数
exogenous calcium
marigold(Tagetes erecta L.)
saline-alkali stress
growth index
gas exchange parameters
chlorophyll fluorescence parameter
