Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related ...Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000(PEG6000)-induced drought stress.Chlorophyll levels,as well as leaf and root biomass,were significantly reduced by drought;drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species.Application of exogenous Ca^(2+)increased the net photosynthetic rate and stomatal conductance of leaves,enhanced water-use efficiency,and increased the length and width of stomata following exposure to drought.Organ-specific physiological responses were observed under different concentrations of Ca^(2+).Application of 5 mmol·L^(-1)Ca^(2+)promoted photosynthesis and antioxidant activity in the leaves,and application of 10 mmol·L^(-1)Ca^(2+)promoted antioxidant activity in the roots.Application of exogenous Ca^(2+)greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress.Overall,our findings indicate that the application of exogenous Ca^(2+)enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants.展开更多
The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fer...The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fertilizer （CRNF）, urea and no nitrogen fertilizer. CRNF showed obvious effects on delaying the senescence and prolonging photosynthetic function duration of rice leaves. Compared with urea, CRNF could significantly increase the chlorophyll content of functional leaves in both early and late rice varieties, and this difference between the treatments became larger as rice growth progressed; CRNF increased the activities of active oxygen scavenging enzymes super oxide dismutase （SOD） and peroxidase （POD）, and decreased the accumulation amount of malondialdehyde （MDA） in functional leaves during leaf aging; Photosynthetic rate of functional leaves in CRNF treatment was significantly higher than that in urea treatment. The result also indicated that CRNF could effectively regulate the contents of indole-3-acetic acid （IAA） and abscisic acid （ABA） in functional leaves; IAA content was higher and ABA content was lower in CRNF treatment than those in urea treatment. Therefore, application of CRNF could increase the rice yield significantly due to these physiological changes in the functional leaves.展开更多
Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits r...Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits related to high efficient photosynthesis. Chlorophyll content, stomatal resistance, and transpiration rate were very important physiological traits related to photosynthesis. But until now, no genetic study on these traits has been reported. A DH population derived from anther culture of ZYQ8/JX17, a typical indica/japonica hybrid was developed,展开更多
[Objectives]This study was conducted to investigate the photosynthetic physiological characteristics of Populus euphratica trees at different forest ages in the desert area of Minqin in response to drought stress.[Met...[Objectives]This study was conducted to investigate the photosynthetic physiological characteristics of Populus euphratica trees at different forest ages in the desert area of Minqin in response to drought stress.[Methods]With P.euphratica trees of different ages in Minqin as the research object,the water characteristics and photosynthetic physiological indexes(chlorophyll,soluble sugar,POD,SOD and MDA)were compared under different conditions.[Results]On the time gradient,the soil water contents of P.euphratica of different ages decreased continuously with the extension of irrigation stop time,but the decreases were small.Under the same stress treatment,the soil water contents of P.euphratica of different ages increased with the deepening of soil layer,but the differences were not significant(P>0.05).Under normal condition,the chlorophyll contents of P.euphratica at three ages gradually increased with the increase of age.The chlorophyll contents in leaves of P.euphratica at different ages were all lower under normal condition and higher under water stress.The changes of POD and SOD activity in leaves of P.euphratica at different ages under different conditions were basically the same,showing that the enzyme activity was higher under water stress than under normal under.The MDA contents in leaves of the young and middle P.euphratica forests were higher under water stress at 7 and 21 d than under normal condition,and the differences were not significant(P>0.05);and the MDA content in leaves of the mature P.euphratica forest was higher under water stress at 21 and 35 d than under normal condition.Drought stress has a certain effect on the photosynthetic physiological characteristics of P.euphratica.In summary,under drought stress,the chlorophyll content,SOD and POD activity,and MDA molar concentration in the leaves of P.euphratica were basically higher than under normal condition,indicating that P.euphratica could resist drought environment through osmotic adjustment and showed strong drought resistance.[Conclusions]This study provides a theoretical reference for the restoration,protection and reconstruction of natural P.euphratica forests in the desert area of Minqin.展开更多
Phytoplankton physiologies are dynamic and have sensitive responses to the ambient environment. In this paper, we examine photosynthetic physiologies of phytoplankton communities with Phyto-PAM in the eastern equatori...Phytoplankton physiologies are dynamic and have sensitive responses to the ambient environment. In this paper, we examine photosynthetic physiologies of phytoplankton communities with Phyto-PAM in the eastern equatorial Indian Ocean during the spring inter-monsoon. Environmental parameters were measured to investigate the coupling between phytoplankton photosynthetic physiologies and their habitats. During the cruise, the water column was highly stratified. The mixed layer extended to about 75 m and was characterized by high temperature (>28°C) and low nutrient level. The Fv/Fm values and chlorophyll a (Chl a) concentrations were lower at the surface, as consequences of nutrient depletion and photo-inhibition. Subsurface Chl a maximum (SCM) occurred between 75 and 100 m, and had the highest Fv/Fm values. The formation of SCM was a balance between nutrient availability and light limitation. The SCM may contribute significantly to pelagic food web and primary production in the water column. Phytoplankton in different layers encountered different light, trophic and hydrographic dynamics and evolved distinct photosynthetic characteristics. Despite of co-limitation of nutrient limitation and photo-inhibition, phytoplankton in the surface layer showed their acclimation to high irradiance, had lower light utilization efficiencies (α: 0.061±0.032) and could exploit a wide range of light irradiance. Whereas, phytoplankton in the SCM layers presented the highest light utilization efficiencies (α: 0.146±0.48), which guaranteed higher photosynthetic capacities under low light level. These results provide insights into phytoplankton photo-adaption strategies in this less explored region.展开更多
Transplantation experiment was carried out using biennial container seedlings and bare root seedlings of Phoebe zhennan S. Lee as materials. In the experiment,it measured the growth indicators such as the seedling hei...Transplantation experiment was carried out using biennial container seedlings and bare root seedlings of Phoebe zhennan S. Lee as materials. In the experiment,it measured the growth indicators such as the seedling height,basal diameter,and number of branches and leaves. Besides,it also measured net photosynthetic rate( Pn),transpiration rate( Tr),stomatal conductance( Gs),intercellular CO_2 concentration( Ci) and soluble sugar,soluble protein,malondialdehyde( MDA) content,superoxide dismutase activity and root activity. The results indicated that the growth indicators of the Phoebe container seedlings performed the best in the plant height,basal diameter,and number of branches and leaves; photosynthetic capacity was the strongest,and the fertilization could enhance the photosynthetic capacity of seedlings; soluble sugar,soluble protein content,superoxide dismutase activity and root activity of Phoebe container seedlings were higher than that of bare root seedlings.展开更多
[Objective] This study aimed to investigate the effects of different concen- trations of antimony and modifier calcium magnesium phosphate on photosynthetic characteristics of edible amaranth, flowering Chinese cabbag...[Objective] This study aimed to investigate the effects of different concen- trations of antimony and modifier calcium magnesium phosphate on photosynthetic characteristics of edible amaranth, flowering Chinese cabbage, spinach and flowering Chinese cabbage. [Method] By outdoor potting simulation experiment, soil matrixes containing 10.00, 20.00, 50.00, 70.00 and 100.00 mg/kg antimony （Sb3＋） were pre- pared; soil without antimony was used as control （CK）. Each pot was loaded with 0.10 kg/kg vegetable special fertilizer, mixed evenly, and divided into two shares： one share was supplemented with 1.75 g/kg modifier calcium magnesium phosphate and mixed evenly; the other share contained no calcium magnesium phosphate. Af- ter the generation of three true leaves, seedlings with uniform growth were trans- planted into the prepared soil matrixes, eights seedlings per pot. Vegetable seedlings were watered regularly to maintain 70% of field capacity. After 45 d, veg- etable plants were harvested and washed clean with distilled water for measurement of indicators of photosynthetic characteristics. [Result] With the increase of antimony concentration, relative chlorophyll content （SPAD value） and net photosynthetic rate of four vegetable species increased first and then declined, while stomatal conduc- tance of vegetable leaves was linearly reduced. [Conclusion] Appropriately adding modifier calcium magnesium phosphate can effectively improve the photosynthetic characteristics of four vegetable species and reduce the toxic effects of heavy metal antimony on vegetables.展开更多
The resurrection plants Ramonda serbica and Ramonda nathaliae are the physiological model plant and endemic species from Balkan Peninsula. Study was carried out to assess the impact of different populations on photosy...The resurrection plants Ramonda serbica and Ramonda nathaliae are the physiological model plant and endemic species from Balkan Peninsula. Study was carried out to assess the impact of different populations on photosynthetic pigment contents and their effect on physiological activity of these species. The experiment was conducted with leaves of R. serbica collected from nine populations in Kosovo, three in Albania and two in Macedonia, while for R. nathaliae four populations in Macedonia. For this purpose plants after collection from their natural populations were kept for 24 hours at constant temperature and humidity and in natural photoperiod. According to our data the pigment contents (Total chl + Carot) of R. serbica, measured as mg per gram dry weight (DW), were higher (7.06 mg·g-1 DW) in Radaci populations (Kosovo) and lower (4.63 mg·g-1 DW) in Jukniu Mountain-Kruja (Albania). On the other hand, the higher (5.28 mg·g-1 DW) of pigment contents (Total chl + Carot) of R. nathaliae were observed in Vorca populations and the lower (4.24 mg·g-1 DW) in Kaparll?k populations. Ratio chlorophyll a/b of R. serbica in Kruja Castle populations from Albania was the higher (3.68) comparing with Zhlebi populations from Kosovo (1.68). Similarly in case of R. nathaliae the higher (3.36) value was in Kaparll?k populations and the lower (3.12) in Matka populations. The data obtained were further analyzed using one-way ANOVA and a significant change was recorded in the different populations. These studies clearly indicate that the Ramonda plants from different ecological habitats there have been changes of photosynthetic pigment contents.展开更多
[Objective]The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate （Pn） with physiological and ecological factors. [Method] The di...[Objective]The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate （Pn） with physiological and ecological factors. [Method] The diurnal variations of photosyn-thesis in leaves of SC205 were studied by LICOR-6400 portable photosynthesis system, and the relationships of the net photosynthetic rate （Pn） with physiological and ecological factors were studied by simple correlation analysis and path analysis. [Result] The curve of diurnal variation of Pn showed single peak at 10：00 am at 24.07 μ mol CO2 m2/s, without showing midday depression; the diurnal changes of stomatal conductance （Gs）, transpiration rate （Tr）, leaf temperature （Tl）, air tempera-ture （Ta） and photosynthetic active radiation （PAR） al showed single peak curves, and there were positive relationships of Pn with Gs, Tr, Tl, Ta and PAR. The diur-nal variations of intercellular CO2 concentration （Ci）, atmospheric CO2 concentration （Ca）, relative humidity （RH） showed in a U-shape curve. There were highly signifi-cant positive correlation of Pn with Gs and PAR; the diurnal variation of Pn had highly significant negative correlations with Ci and Ca. The direct impact of physio-logical factors on Pn was as fol ows： Ci＆gt;Gs＆gt;Tl＆gt;Tr, and the direct impact of ecologi-cal factors was RH＆gt;PAR＆gt;Ca＆gt;Ta. [Conclusion] The research showed that Ci, Gs and Tr play very important roles in the changes of Pn among the physiological fac-tors, and PAR and Ca affect the changes of Pn among the ecological factors.展开更多
针对绿洲灌区玉米生产中普遍水肥投入大、利用效率低等问题,通过研究不同灌水量和有机无机肥等氮配施对玉米光合生理、籽粒产量和品质的影响,以期获得最佳的灌水水平和有机无机肥等氮配施比例。2021—2022年,在绿洲灌区采用两因素裂区...针对绿洲灌区玉米生产中普遍水肥投入大、利用效率低等问题,通过研究不同灌水量和有机无机肥等氮配施对玉米光合生理、籽粒产量和品质的影响,以期获得最佳的灌水水平和有机无机肥等氮配施比例。2021—2022年,在绿洲灌区采用两因素裂区试验设计,主区为2个灌水水平(传统灌水和减量20%灌水),副区为5个有机无机肥等氮配施比例(全施无机氮肥、75%无机氮肥+25%有机肥、50%无机氮肥+50%有机肥、25%无机氮肥+75%有机肥和全施有机肥),探究玉米光合生理、籽粒产量和品质对不同水氮管理模式的响应特征。结果表明,与传统灌水(I2)相比,减量20%灌水(I1)降低了玉米叶面积指数(leaf area index,LAI)、光合势(photosynthetic potential,LAD)、净光合速率(Pn)、蒸腾速率(Tr)和气孔导度(Gs),提高了胞间CO_(2)浓度(Ci)、籽粒蛋白质含量和籽粒苏氨酸含量;有机无机肥配施对玉米光合生理指标、籽粒产量和品质都有显著影响,随有机肥比例增加,有机无机肥配施对玉米的影响会逐渐从正效应变为负效应;与传统灌水结合全施无机氮肥(I2F1)相比,减量20%灌水结合75%无机氮肥+25%有机肥(I1F2)玉米平均叶面积指数(mean leaf area index,MLAI)提高了6.9%~7.1%,总光合势(total photosynthetic potential,TLAD)无显著变化;玉米吐丝期-蜡熟期LAI提高了5.0%~11.4%,吐丝期-蜡熟期LAD提高了7.5%~9.1%。I1F2较I2F1提高了玉米抽雄期-蜡熟期叶绿素含量(chlorophyll content,SPAD)、Pn、Tr和Gs,降低了Ci。2年内I1F2较I2F1玉米增产12.0%~12.5%,籽粒中蛋白含量提高了6.9%~18.9%,籽粒中苯丙氨酸、赖氨酸、苏氨酸、色氨酸、亮氨酸、异亮氨酸和缬氨酸含量分别提高了29.6%~43.3%、77.7%~93.3%、49.7%~51.5%、18.4%~28.6%、39.5%~46.0%、57.4%~78.1%和35.1%~41.3%。其他处理对玉米光合生理、籽粒产量及品质指标也有一定影响,但综合2年结果,I1F2影响更显著。因此,减量20%灌水(3240 m^(3)hm^(–2))结合75%无机化学氮肥(270 kg hm^(–2))配施25%有机肥(90 kg hm^(–2))是实现西北灌区玉米高产优质生产目标的适宜水氮管理模式。展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2018YFD1000400)Innovative Program for Graduate Student of Qingdao Agricultural University(Grant No.QNYCX22045).
文摘Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000(PEG6000)-induced drought stress.Chlorophyll levels,as well as leaf and root biomass,were significantly reduced by drought;drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species.Application of exogenous Ca^(2+)increased the net photosynthetic rate and stomatal conductance of leaves,enhanced water-use efficiency,and increased the length and width of stomata following exposure to drought.Organ-specific physiological responses were observed under different concentrations of Ca^(2+).Application of 5 mmol·L^(-1)Ca^(2+)promoted photosynthesis and antioxidant activity in the leaves,and application of 10 mmol·L^(-1)Ca^(2+)promoted antioxidant activity in the roots.Application of exogenous Ca^(2+)greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress.Overall,our findings indicate that the application of exogenous Ca^(2+)enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants.
基金National Natural Science Foundation of China(30270770)Foundation for Achievement Transfer(02EFN214301156) Key Subject Foundation of Hunan Academy of Agricultural Sciences(03-05).
文摘The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fertilizer （CRNF）, urea and no nitrogen fertilizer. CRNF showed obvious effects on delaying the senescence and prolonging photosynthetic function duration of rice leaves. Compared with urea, CRNF could significantly increase the chlorophyll content of functional leaves in both early and late rice varieties, and this difference between the treatments became larger as rice growth progressed; CRNF increased the activities of active oxygen scavenging enzymes super oxide dismutase （SOD） and peroxidase （POD）, and decreased the accumulation amount of malondialdehyde （MDA） in functional leaves during leaf aging; Photosynthetic rate of functional leaves in CRNF treatment was significantly higher than that in urea treatment. The result also indicated that CRNF could effectively regulate the contents of indole-3-acetic acid （IAA） and abscisic acid （ABA） in functional leaves; IAA content was higher and ABA content was lower in CRNF treatment than those in urea treatment. Therefore, application of CRNF could increase the rice yield significantly due to these physiological changes in the functional leaves.
文摘Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits related to high efficient photosynthesis. Chlorophyll content, stomatal resistance, and transpiration rate were very important physiological traits related to photosynthesis. But until now, no genetic study on these traits has been reported. A DH population derived from anther culture of ZYQ8/JX17, a typical indica/japonica hybrid was developed,
基金Supported by Research and Development Program of Gansu Province(17YF1FA113)The National Natural Science Foundation of China(31560128).
文摘[Objectives]This study was conducted to investigate the photosynthetic physiological characteristics of Populus euphratica trees at different forest ages in the desert area of Minqin in response to drought stress.[Methods]With P.euphratica trees of different ages in Minqin as the research object,the water characteristics and photosynthetic physiological indexes(chlorophyll,soluble sugar,POD,SOD and MDA)were compared under different conditions.[Results]On the time gradient,the soil water contents of P.euphratica of different ages decreased continuously with the extension of irrigation stop time,but the decreases were small.Under the same stress treatment,the soil water contents of P.euphratica of different ages increased with the deepening of soil layer,but the differences were not significant(P>0.05).Under normal condition,the chlorophyll contents of P.euphratica at three ages gradually increased with the increase of age.The chlorophyll contents in leaves of P.euphratica at different ages were all lower under normal condition and higher under water stress.The changes of POD and SOD activity in leaves of P.euphratica at different ages under different conditions were basically the same,showing that the enzyme activity was higher under water stress than under normal under.The MDA contents in leaves of the young and middle P.euphratica forests were higher under water stress at 7 and 21 d than under normal condition,and the differences were not significant(P>0.05);and the MDA content in leaves of the mature P.euphratica forest was higher under water stress at 21 and 35 d than under normal condition.Drought stress has a certain effect on the photosynthetic physiological characteristics of P.euphratica.In summary,under drought stress,the chlorophyll content,SOD and POD activity,and MDA molar concentration in the leaves of P.euphratica were basically higher than under normal condition,indicating that P.euphratica could resist drought environment through osmotic adjustment and showed strong drought resistance.[Conclusions]This study provides a theoretical reference for the restoration,protection and reconstruction of natural P.euphratica forests in the desert area of Minqin.
基金The Global Change and Air-Sea Interaction Program under contract No.GASI-03-01-03-03the S&T Innovation Project of the Qingdao National Laboratory for Marine Science and Technology under contract No.2016ASKJ14the FIO Basic Research Fund under contract No.2013T04
文摘Phytoplankton physiologies are dynamic and have sensitive responses to the ambient environment. In this paper, we examine photosynthetic physiologies of phytoplankton communities with Phyto-PAM in the eastern equatorial Indian Ocean during the spring inter-monsoon. Environmental parameters were measured to investigate the coupling between phytoplankton photosynthetic physiologies and their habitats. During the cruise, the water column was highly stratified. The mixed layer extended to about 75 m and was characterized by high temperature (>28°C) and low nutrient level. The Fv/Fm values and chlorophyll a (Chl a) concentrations were lower at the surface, as consequences of nutrient depletion and photo-inhibition. Subsurface Chl a maximum (SCM) occurred between 75 and 100 m, and had the highest Fv/Fm values. The formation of SCM was a balance between nutrient availability and light limitation. The SCM may contribute significantly to pelagic food web and primary production in the water column. Phytoplankton in different layers encountered different light, trophic and hydrographic dynamics and evolved distinct photosynthetic characteristics. Despite of co-limitation of nutrient limitation and photo-inhibition, phytoplankton in the surface layer showed their acclimation to high irradiance, had lower light utilization efficiencies (α: 0.061±0.032) and could exploit a wide range of light irradiance. Whereas, phytoplankton in the SCM layers presented the highest light utilization efficiencies (α: 0.146±0.48), which guaranteed higher photosynthetic capacities under low light level. These results provide insights into phytoplankton photo-adaption strategies in this less explored region.
基金Supported by Key Technology R&D Program of Hubei Province(2013BBB24)Second Survey of Key Wild Plant Resources under Protection in China"Special Survey of Phoebe zhennan S.Lee Resources in Hubei Province"
文摘Transplantation experiment was carried out using biennial container seedlings and bare root seedlings of Phoebe zhennan S. Lee as materials. In the experiment,it measured the growth indicators such as the seedling height,basal diameter,and number of branches and leaves. Besides,it also measured net photosynthetic rate( Pn),transpiration rate( Tr),stomatal conductance( Gs),intercellular CO_2 concentration( Ci) and soluble sugar,soluble protein,malondialdehyde( MDA) content,superoxide dismutase activity and root activity. The results indicated that the growth indicators of the Phoebe container seedlings performed the best in the plant height,basal diameter,and number of branches and leaves; photosynthetic capacity was the strongest,and the fertilization could enhance the photosynthetic capacity of seedlings; soluble sugar,soluble protein content,superoxide dismutase activity and root activity of Phoebe container seedlings were higher than that of bare root seedlings.
基金Supported by Fund of Director of Hunan Institute of HorticultureProject for Cultivation Post in Citrus Industry System of Hunan Province(2013)~~
文摘[Objective] This study aimed to investigate the effects of different concen- trations of antimony and modifier calcium magnesium phosphate on photosynthetic characteristics of edible amaranth, flowering Chinese cabbage, spinach and flowering Chinese cabbage. [Method] By outdoor potting simulation experiment, soil matrixes containing 10.00, 20.00, 50.00, 70.00 and 100.00 mg/kg antimony （Sb3＋） were pre- pared; soil without antimony was used as control （CK）. Each pot was loaded with 0.10 kg/kg vegetable special fertilizer, mixed evenly, and divided into two shares： one share was supplemented with 1.75 g/kg modifier calcium magnesium phosphate and mixed evenly; the other share contained no calcium magnesium phosphate. Af- ter the generation of three true leaves, seedlings with uniform growth were trans- planted into the prepared soil matrixes, eights seedlings per pot. Vegetable seedlings were watered regularly to maintain 70% of field capacity. After 45 d, veg- etable plants were harvested and washed clean with distilled water for measurement of indicators of photosynthetic characteristics. [Result] With the increase of antimony concentration, relative chlorophyll content （SPAD value） and net photosynthetic rate of four vegetable species increased first and then declined, while stomatal conduc- tance of vegetable leaves was linearly reduced. [Conclusion] Appropriately adding modifier calcium magnesium phosphate can effectively improve the photosynthetic characteristics of four vegetable species and reduce the toxic effects of heavy metal antimony on vegetables.
文摘The resurrection plants Ramonda serbica and Ramonda nathaliae are the physiological model plant and endemic species from Balkan Peninsula. Study was carried out to assess the impact of different populations on photosynthetic pigment contents and their effect on physiological activity of these species. The experiment was conducted with leaves of R. serbica collected from nine populations in Kosovo, three in Albania and two in Macedonia, while for R. nathaliae four populations in Macedonia. For this purpose plants after collection from their natural populations were kept for 24 hours at constant temperature and humidity and in natural photoperiod. According to our data the pigment contents (Total chl + Carot) of R. serbica, measured as mg per gram dry weight (DW), were higher (7.06 mg·g-1 DW) in Radaci populations (Kosovo) and lower (4.63 mg·g-1 DW) in Jukniu Mountain-Kruja (Albania). On the other hand, the higher (5.28 mg·g-1 DW) of pigment contents (Total chl + Carot) of R. nathaliae were observed in Vorca populations and the lower (4.24 mg·g-1 DW) in Kaparll?k populations. Ratio chlorophyll a/b of R. serbica in Kruja Castle populations from Albania was the higher (3.68) comparing with Zhlebi populations from Kosovo (1.68). Similarly in case of R. nathaliae the higher (3.36) value was in Kaparll?k populations and the lower (3.12) in Matka populations. The data obtained were further analyzed using one-way ANOVA and a significant change was recorded in the different populations. These studies clearly indicate that the Ramonda plants from different ecological habitats there have been changes of photosynthetic pigment contents.
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-12)
文摘[Objective]The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate （Pn） with physiological and ecological factors. [Method] The diurnal variations of photosyn-thesis in leaves of SC205 were studied by LICOR-6400 portable photosynthesis system, and the relationships of the net photosynthetic rate （Pn） with physiological and ecological factors were studied by simple correlation analysis and path analysis. [Result] The curve of diurnal variation of Pn showed single peak at 10：00 am at 24.07 μ mol CO2 m2/s, without showing midday depression; the diurnal changes of stomatal conductance （Gs）, transpiration rate （Tr）, leaf temperature （Tl）, air tempera-ture （Ta） and photosynthetic active radiation （PAR） al showed single peak curves, and there were positive relationships of Pn with Gs, Tr, Tl, Ta and PAR. The diur-nal variations of intercellular CO2 concentration （Ci）, atmospheric CO2 concentration （Ca）, relative humidity （RH） showed in a U-shape curve. There were highly signifi-cant positive correlation of Pn with Gs and PAR; the diurnal variation of Pn had highly significant negative correlations with Ci and Ca. The direct impact of physio-logical factors on Pn was as fol ows： Ci＆gt;Gs＆gt;Tl＆gt;Tr, and the direct impact of ecologi-cal factors was RH＆gt;PAR＆gt;Ca＆gt;Ta. [Conclusion] The research showed that Ci, Gs and Tr play very important roles in the changes of Pn among the physiological fac-tors, and PAR and Ca affect the changes of Pn among the ecological factors.
文摘针对绿洲灌区玉米生产中普遍水肥投入大、利用效率低等问题,通过研究不同灌水量和有机无机肥等氮配施对玉米光合生理、籽粒产量和品质的影响,以期获得最佳的灌水水平和有机无机肥等氮配施比例。2021—2022年,在绿洲灌区采用两因素裂区试验设计,主区为2个灌水水平(传统灌水和减量20%灌水),副区为5个有机无机肥等氮配施比例(全施无机氮肥、75%无机氮肥+25%有机肥、50%无机氮肥+50%有机肥、25%无机氮肥+75%有机肥和全施有机肥),探究玉米光合生理、籽粒产量和品质对不同水氮管理模式的响应特征。结果表明,与传统灌水(I2)相比,减量20%灌水(I1)降低了玉米叶面积指数(leaf area index,LAI)、光合势(photosynthetic potential,LAD)、净光合速率(Pn)、蒸腾速率(Tr)和气孔导度(Gs),提高了胞间CO_(2)浓度(Ci)、籽粒蛋白质含量和籽粒苏氨酸含量;有机无机肥配施对玉米光合生理指标、籽粒产量和品质都有显著影响,随有机肥比例增加,有机无机肥配施对玉米的影响会逐渐从正效应变为负效应;与传统灌水结合全施无机氮肥(I2F1)相比,减量20%灌水结合75%无机氮肥+25%有机肥(I1F2)玉米平均叶面积指数(mean leaf area index,MLAI)提高了6.9%~7.1%,总光合势(total photosynthetic potential,TLAD)无显著变化;玉米吐丝期-蜡熟期LAI提高了5.0%~11.4%,吐丝期-蜡熟期LAD提高了7.5%~9.1%。I1F2较I2F1提高了玉米抽雄期-蜡熟期叶绿素含量(chlorophyll content,SPAD)、Pn、Tr和Gs,降低了Ci。2年内I1F2较I2F1玉米增产12.0%~12.5%,籽粒中蛋白含量提高了6.9%~18.9%,籽粒中苯丙氨酸、赖氨酸、苏氨酸、色氨酸、亮氨酸、异亮氨酸和缬氨酸含量分别提高了29.6%~43.3%、77.7%~93.3%、49.7%~51.5%、18.4%~28.6%、39.5%~46.0%、57.4%~78.1%和35.1%~41.3%。其他处理对玉米光合生理、籽粒产量及品质指标也有一定影响,但综合2年结果,I1F2影响更显著。因此,减量20%灌水(3240 m^(3)hm^(–2))结合75%无机化学氮肥(270 kg hm^(–2))配施25%有机肥(90 kg hm^(–2))是实现西北灌区玉米高产优质生产目标的适宜水氮管理模式。
