期刊文献+
共找到3,564篇文章
< 1 2 179 >
每页显示 20 50 100
Post Cryopreservation Growth Kinetic and Photosynthetic Assessment of an Acid Tolerant Strain of Stichococcus bacillaris
1
作者 Marzia Licata Luigi Marra +5 位作者 Nunzia Nappi Elena Aurino Feliciana Oliva Antonino De Natale Donato Giovannelli Antonino Pollio 《Natural Resources》 2024年第5期130-148,共19页
Preserving microbial diversity has become a strategic undertaking. Thus, ex situ microalgal culture conservation results in strategic and functional resource in both biodiversity protection and application domains. Cr... Preserving microbial diversity has become a strategic undertaking. Thus, ex situ microalgal culture conservation results in strategic and functional resource in both biodiversity protection and application domains. Cryopreservation of microalgae has been practiced since the 1960s and is now considered the optimal preservation strategy. Furthermore, the overall monitoring during growth of cultures after freezing/thawing protocols was hardly investigated and there is poor evaluation related to preserve especially the photosystem apparatus. The present study focuses on Stichococcus bacillaris as case study for short-term cryopreservation at −80 °C storage. Various freezing pretreatments using cryoprotective agents, and two thawing methods were compared introducing a novel variable to evaluate viability recovery and assessing growth kinetics of cultures immediately after thawing and after a series batch cultivation. Photosynthetic rate and pigments assessment were proposed to evaluate hidden metabolic cell damage. Results underline cryoprotective agents can increase the kinetic recovery of preserved cells in terms of reduction of lag phase during batch cultivation tests: the use of dimethyl sulfoxide and glycerol granted a growth comparable to unpreserved cells when sudden thawing occurs after 24 hours of storage, but recovery after preservation is less sensitive to cryoprotective agents when gradual thawing and 1 month of storage is considered. However, cells are always able to restore their physiological pathways even without agents, so their kinetic effect has been proved and quantified. Interestingly, both the photosynthetic efficiency and the ratio between total chlorophyll and carotenoids are comparable (0.75 F<sub>v</sub>/F<sub>m</sub>, 2.2 ± 0.25 g/g) to unpreserved cells and they are unsensitive to chosen agents, but the ratio between chlorophyll a and chlorophyll b was clearly altered (up to 10 times), suggesting that photoactive pigments relative proportions can result in similar growth kinetic performances. Long-term studies will be carried out to assess whether the differences found could cause chronic damage to photosystem efficiency of S. bacillaris cultures. 展开更多
关键词 MICROALGAE Stichococcus bacillaris CRYOPRESERVATION Growth Kinetic photosynthetic rate
下载PDF
Leaf Photosynthetic Rate and Related Influencing Factors in Super High-yield Combination C Liangyou H255 被引量:8
2
作者 贺安娜 吴厚雄 +2 位作者 蒋向辉 何超 徐良骏 《Agricultural Science & Technology》 CAS 2008年第2期23-25,29,共4页
[ Objective] Study on the photosynthesis and influencing factors in super high-yield combination C Liangyou H255. [ Method] The photosynthetic characteristies were measured at a hot and muggy day under natural conditi... [ Objective] Study on the photosynthesis and influencing factors in super high-yield combination C Liangyou H255. [ Method] The photosynthetic characteristies were measured at a hot and muggy day under natural conditions. [ Result] A respective single peak at 11:30 was observed in diurnal variation curves of net photosynthetic rate (Pn) and transpiration rate(Tr). Correlation analysis shows that Pn presents an extremely significant correlation with photon flux densities (PFD) of photosynthetically active radiation, in comparison assumes a significant correlation either with stomatal conductance (Gs) or with ambient CO2 concentration (Ca). [ Conclusion] Gs followed by PFD presented most influence on Pn of super high-yield combination C Liangyou H255. 展开更多
关键词 Net photosynthetic rate Diurnal variation Correlation analysis Path analysis
下载PDF
Study on the Daily Change of Photosynthetic Rate for Prunus domestica × armeniacain Different Seasons 被引量:3
3
作者 李雯雯 冯贝贝 +5 位作者 魏雅君 牛莹莹 徐业勇 王明 杨红丽 廖康 《Agricultural Science & Technology》 CAS 2016年第4期838-844,941,共8页
[Objective] The aim of this study was to explore the daily change of photosyntheticratefor Prunus domestica ×armeniacain different growing seasons. The study can provide theoretical basis for arid area high yield... [Objective] The aim of this study was to explore the daily change of photosyntheticratefor Prunus domestica ×armeniacain different growing seasons. The study can provide theoretical basis for arid area high yield and quality cultivation.[Method] The photosynthetic physiological properties of leaves of different types of Prunus domestica × armeniaca were measured by the Li-6400 portable photosynthesis system indifferent seasons. By this method could analysis of photosyntheticcharacteristicsfor different types of Prunus domestica×armeniaca in different seasons.[Result] Daily change of photosyntheticrate(Pn) for Prunus domestica×armeniaca in differentseasons showed a "double-peak" curve. The peak values were at 10:00 and16:00. The Pn of ‘Fengweihuanghou', ‘Konglongdan', ‘Weihou', ‘Weiwang' and‘Weidi' reached the maximum in July, theywere 13.75, 14.76, 12.96, 13.3, and 11.9μmol/(m^2·s), respectively. The Pn of Prunus domestica×armeniaca reached minimumin August, they were 9.78, 10.71, 12.02, 10.43 μmol/(m^2·s). The Pn overall average of ‘Konglongdan' was highest,it reached 12.65 μmol/(m^2·s).The Pn overall average of ‘Weiwang' was lowest, it reached 11.31μmol/(m^2·s). There were extremely significant positive correlation between the Pn and Gs(P0.01). [Conclusion] Daily change of photosyntheticrate for Prunus domestica ×armeniaca in differentseasons showed a "double-peak" curve, showing significant phenomenon of "midday depression".The photosynthesis intensity of Prunus domestica ×armeniaca was strongest in July, and the photosynthesis intensity was weakest in August. ‘Konglongdan'showed the strongest photosynthesis capacity, ‘Weihou' and ‘Weiwang', followed.There were highest correlation between the Pn and stoma conductance(Gs). 展开更多
关键词 Prunus domestica × armeniaca Net photosynthetic rate Daily change of photosynthetic rate Environmental factors
下载PDF
Diurnal changes in net photosynthetic rate of Pueraria lobataand its impact factors 被引量:1
4
作者 DING You-fang WANG Cai-yun +5 位作者 Neo C MOKGOLODI ZHANG Xiao-xia SHI Ling-ling ZHANG Yun-wei YANG Fu-yu LIU Yu-jun 《Forestry Studies in China》 CAS 2011年第1期57-63,共7页
In order to identify the relationship between diurnal changes in the net photosynthetic rate(Pn) of Pueraria lobata and environmental factors,diurnal changes in the Pn of leaves of two P.lobata cultivars were measur... In order to identify the relationship between diurnal changes in the net photosynthetic rate(Pn) of Pueraria lobata and environmental factors,diurnal changes in the Pn of leaves of two P.lobata cultivars were measured using a CIRAS-1 portable photosynthesis measurement system(PP-Systems,UK).The results show that diurnal changes in Pn of both cultivars could be interpreted as double-peak curves,indicating the occurrence of an obvious midday depression.Further analyses indicate that the correlation between Pn and stomatal conductance was positive and extremely significant(p 〈 0.01).The correlations of Pn with intercellular CO2 concentration and transpiration rate were positive and significant(p 〈 0.05),while the correlations of Pn with air and leaf temperatures were negative and significant(p 〈 0.05).The results indicate that among the factors affecting photosynthetic properties,some can be grouped as stomatal limitations while others are non-stomatal limitations. 展开更多
关键词 Pueraria lobata net photosynthetic rate (pn diumal change environmental factors
下载PDF
Effects of Chilling Stress on Photosynthetic Rate and Chlorophyll Fluorescence Parameter in Seedlings of Two Rice Cultivars Differing in Cold Tolerance 被引量:5
5
作者 WANG Guo-li Guo Zhen-fei 《Rice science》 SCIE 2005年第3期187-191,共5页
A cold-tolerant cultivar, Xiangnuo 1, and a cold-sensitive cultivar, IR50, were used to study the influence of chilling on photosynthetic rate and chlorophyll fluorescence parameters in rice seedlings. The photosynthe... A cold-tolerant cultivar, Xiangnuo 1, and a cold-sensitive cultivar, IR50, were used to study the influence of chilling on photosynthetic rate and chlorophyll fluorescence parameters in rice seedlings. The photosynthetic rates declined dramatically during chilling, and decreased by 48.7% and 67.5% in Xiangnuo 1 and IR50 seedlings, respectively, after being subjected to chilling treatment for two days. Chlorophyll fluorescence measurements showed that relatively higher qp and qNP in Xiangnuo 1 were maintained to dissipate the redundant excitation energy and protect the reaction centers from chill injury; accordingly, redundant excitation energy accumulated less in the reaction centers, and antenna systems were less injured by chilling in Xiangnuo 1. On the contrary, in IR50, qp and qNP declined rapidly while Eg increased, as the chilling persisted. This result indicated that the reaction centers and antenna systems in IR50 were damaged severely by chilling, which led to the lower photosynthetic rate. 展开更多
关键词 CHILLING RICE photosynthetic rate chlorophyll fluorescence analysis
下载PDF
Comparison of Net Photosynthetic Rate in Leaves of Soybean with Different Yield Levels 被引量:6
6
作者 Li Da-yong Zhang Zhi-an +2 位作者 Zheng Dian-jun Jiang Li-yan Wang Yuan-li 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第3期14-19,共6页
A total of nine soybean (Glycine max (L.) Merr.) cultivars were divided into three yield levels which were planted under the same environmental condition. The net photosynthetic rate was measured by LI-6400 portab... A total of nine soybean (Glycine max (L.) Merr.) cultivars were divided into three yield levels which were planted under the same environmental condition. The net photosynthetic rate was measured by LI-6400 portable photosynthesis system. The chlorophyll content and specific leaf weight were measured with regular methods. The results showed that the specific leaf weight, chlorophyll content and net photosynthetic rate of high yield varieties were higher than those of low yield varieties. The yield had a significantly positive correlation with the net photosynthetic rate. With the improvement of modem technology, the net photosynthetic rate could be measured quickly and exactly. Hence, net photosynthetic rate could be used as an effective index in the selection of high yield soybean. 展开更多
关键词 SOYBEAN YIELD net photosynthetic rate specific leaf weight chlorophyll content
下载PDF
Effect of Nitrogen Fertilizer on Photosynthetic Rate of Leymus chinensis in Grassland of Different Degrading Degrees
7
作者 王明铭 鲍雅静 +3 位作者 李政海 杨绍欢 焦静平 郭燕宇 《Agricultural Science & Technology》 CAS 2012年第9期1929-1932,1957,共5页
[Objective] This study aimed to investigate the effect of nitrogen fertilizer on photosynthetic rate of Leymus chinensis in the grasslands of different degrading degrees. [Method] With the L. chinensis in Inner Mongol... [Objective] This study aimed to investigate the effect of nitrogen fertilizer on photosynthetic rate of Leymus chinensis in the grasslands of different degrading degrees. [Method] With the L. chinensis in Inner Mongolia Baiyinxile Ranch as the research object, different rations of nitrogen fertilizer were applied to the grassland (0, 30, 50, 80 g/m^2). The effect of different gradients of nitrogen fertilizer on photo- synthetic rate of Leymus chinensis, and the effect on grasslands of different degrading degrees were analyzed. [Result] The photosynthetic rate of L. chinensis in- creased with the increase of nitrogen gradients; in the grassland communities with different degrading degrees, the responses of the photosynthetic rate of L. chinensis to nitrogen fertilizer were different, and the response in the grassland with severe degradation was the best. [Conclusion] Nitrogen fertilizer played an important role in enhancing the restoration degree of grassland. 展开更多
关键词 Leymus chinensis Nitrogen fertilizer photosynthetic rate
下载PDF
Relationship Between Diurnal Changes of Net Photosynthetic Rate and Influencing Factors in Rice under Saline Sodic Stress 被引量:3
8
作者 YANG Fu LIANG Zheng-wei +1 位作者 WANG Zhi-chun CHEN Yuan 《Rice science》 SCIE 2008年第2期119-124,共6页
The net photosynthetic rate of flag leaves and influencing factors under saline sodic soil conditions were investigated at the full heading stage of rice. The net photosynthetic rate of rice leaves showed a double-pea... The net photosynthetic rate of flag leaves and influencing factors under saline sodic soil conditions were investigated at the full heading stage of rice. The net photosynthetic rate of rice leaves showed a double-peak curve in a day in both non-saline sodic and saline sodic soil treatments. The first peak of the net photosynthetic rate appeared at 9:00-10:00 and 9:00 in the saline sodic and non-saline sodic soil treatments, respectively, whereas the second peak both at 14:00. The midday depression of the net photosynthetic rate always appeared regardless of non-saline sodic or saline sodic soil conditions. In addition, the net photosynthetic rate significantly decreased in all day under saline sodic conditions compared with that under non-saline sodic conditions. Some differences were observed in correlation characters between the net photosynthetic rate and all influencing factors during 9:00-13:00. Under non-saline sodic conditions, the diurnal changes of the net photosynthetic rate in a day were mainly caused by stomatal conductance, and the limitation value and the stomatal factors served as determinants; whereas under saline sodic stress, the diurnal changes of the net photosynthetic rate in a day were mainly caused by non stomatal factors including light intensity and air temperature. 展开更多
关键词 RICE saline sodic stress diurnal changes net photosynthetic rate influencing factors RELATIONSHIP
下载PDF
Effect of Water Deficit Stress on Photosynthetic Characteristics of Jatropha curcas
9
作者 Kesego Makholwa Baleseng Moseki Goitseone Malambane 《American Journal of Plant Sciences》 CAS 2023年第1期104-112,共9页
The need to mitigate climate change cannot be more emphasized, which arises, as a result of increases in CO<sub>2</sub> emissions due to anthropogenic activities. Given the current world energy problems of... The need to mitigate climate change cannot be more emphasized, which arises, as a result of increases in CO<sub>2</sub> emissions due to anthropogenic activities. Given the current world energy problems of high fossil fuel consumption which plays a pivotal role in the greenhouse effect, Jatropha curcas biodiesel has been considered a potential alternative source of clean energy (biodiesel is carbon neutral). However, the ability of Jatropha curcas, as a candidate source of alternative of clean energy, to grow in marginal and dry soils, has been poorly elucidated. This study, therefore aimed at investigating whether Jatropha curcas leaves could switch from carrying out C<sub>3</sub> photosynthetic pathway to Crassulacean Acid Metabolism (CAM) as a strategy to improve its water deficit tolerance. Thirty-five-day-old Jatropha curcas accessions, from three different climatic zones of Botswana, viz., Mmadinare (Central zone), Thamaga (Southern zone) and Maun (Northern zone), were subjected to water stress, by with-holding irrigation with half-strength Hoagland culture solution. Net photosynthetic rate, transpiration and stomatal conductance were measured at weekly intervals. The leaf pH was measured to determine whether there was a decrease in pH (leaf acidification) of the leaves during the night, when the plants experienced water deficit stress. All the accessions exhibited marked reduction in all the measured photosynthetic characteristics when experience water deficit stress. However, a measurable CO<sub>2</sub> uptake was carried out by leaves of all the accessions, in the wake of marked decreases in stomatal conductance. There is evidence to suggest that when exposed to water stress J. curcas accessions switch from C<sub>3</sub> mode of photosynthesis to CAM photosynthetic pathway. This is attested to by the slightly low leaf pH at night. Thamaga accession exhibited an earlier stomatal closure than the other two accessions. This resulted in Thamaga accession displaying a slightly lower dry weight than both Mmadinare and Maun accessions. It could be concluded that Jatropha curcas appeared to tolerate water deficit stress due to its ability of switching from C<sub>3</sub> photosynthetic pathway to the CAM photosynthetic pathway, but with a cost to biomass accumulation, as demonstrated by slightly more reduced CO<sub>2</sub> assimilation by Thamaga accession, than the other two accessions. 展开更多
关键词 Jatropha curcas BIODIESEL Crassulacean Acid Metabolism Net photosynthetic rate Stomatal Conductance
下载PDF
Effects of elevated CO_2 on net photosynthetic rate of trees in Changbai Mountain 被引量:1
10
作者 王琛瑞 韩士杰 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第4期211-213,共3页
Net photosynthetic rates (NPRs) of four species seedlings, Pinus koraiensis, Ptrius Syvestriformis,Fraxinus mandshuthe and Phellodendron amurense, were measured at different CO2 concentrations and time respectively in... Net photosynthetic rates (NPRs) of four species seedlings, Pinus koraiensis, Ptrius Syvestriformis,Fraxinus mandshuthe and Phellodendron amurense, were measured at different CO2 concentrations and time respectively in Changbai Mountain during the growing season in 1999. The seedlings were cultivated in open-top chambers (OTCs), located outdoors and exposed to natural sunlight. The experimental objects were divided into four groups by tree species. CO2 concentrations in chambers were kept at 500 μL-L-1 and 700 μL-L-1 and contrast chamber and contrast field were set. The results showed that the effects of elevated CO2 on NPR of the trees strongly depended on tree species and time. NPRs of Pin us koreaipsis and Pinus syvestriformis seedfings increased with the rising of CO2 concentration, while that of Phellodron amurense and haus mandshurica increased at some time and decreased at another time. 展开更多
关键词 Elevated CO_2 Net photosynthetic rate Trees Changbai Mountain
下载PDF
Different Deficit Irrigation Lower Limits and Irrigation Quotas Affect the Yield and Water Use Efficiency of Winter Wheat by Regulating Photosynthetic Characteristics
11
作者 Huiqin Li Mingzhi Zhang +1 位作者 Na Xiao Haijian Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第12期3211-3236,共26页
To determine suitable thresholds for deficit irrigation of winter wheat in the well-irrigated area of the Huang-Huai-Hai Plain,we investigated the effects of different deficit irrigation lower limits and quotas on the... To determine suitable thresholds for deficit irrigation of winter wheat in the well-irrigated area of the Huang-Huai-Hai Plain,we investigated the effects of different deficit irrigation lower limits and quotas on the photosynthetic characteristics and grain yield of winter wheat.Four irrigation lower limits were set for initiating irrigation(i.e.,light drought(LD,50%,55%,60%and 50%of field holding capacity(FC)at the seedling-regreening,jointing,heading and filling-ripening stages,respectively),medium drought(MD,40%,50%,55%and 45%of FC at the same stages,respectively),adequate moisture(CK1,60%,65%,70%and 60%of FC at the same stages,respectively),heavy drought(CK2,35%,40%,45%and 40%of FC at the same stages,respectively))and five irrigation quota per event(30,60,90,120 and 180 mm)were set for each lower limit.We found that the increase of drought stress is conducive to normal photosynthesis of winter wheat leaves which is supported by the following findings.First,photosynthetic rate(Pn)of LD60 treatment was higher than that of LD30,LD90,LD120,LD180,MD30,MD60,MD90,MD120 and MD180.Then,Under the 90 mm irrigation quota treatment,the yield of winter wheat basically increased with the increase of irrigation’s lower limit.Moreover,With the increase in irrigation quota,the yield of winter wheat increased,and the water use efficiency(WUE)of winter wheat increased at first and then decreased.In addition,compared with the LD30,MD30,MD60,MD90,MD120,and MD180,the yield of winter wheat in LD60 treatment increased by about 3.23%(3-year average),32.3%,19.9%,11.7%,10.1%,and 14.6%.At the same time,the WUE with LD60 treatment of winter wheat was significantly higher than LD90,LD120,LD180,MD30,MD60,MD90,MD120,MD180 treatments.There was a positive correlation between soil volumetric water content and Pn and between yield and Pn.The key period for yield formation in winter wheat is 180 days after sowing.In conclusion,to achieve the dual goals of stable winter wheat yield and efficient utilization of water resources in this region,the suitable threshold for initiating deficit irrigation of winter wheat is the LD60 treatment.This conclusion provides data support for water-saving and stable yield of winter wheat in this area. 展开更多
关键词 Irrigation lower limit irrigation quota soil volume moisture content photosynthetic rate YIELD regression analysis
下载PDF
Linear Relationships between Photosynthetic Rate and Photochemical Energy Expressed by <i>PAR</i>×<i>Fv/Fm</i> 被引量:1
12
作者 Dongbao Sun Qingsuo Wang 《American Journal of Plant Sciences》 2018年第2期125-138,共14页
Photosynthetic rate (Pn) of plants is simultaneously affected by photosynthetically active radiation (PAR) and maximum yield of primary photochemistry (Fv/Fm). In order to explore the quantitative relationship between... Photosynthetic rate (Pn) of plants is simultaneously affected by photosynthetically active radiation (PAR) and maximum yield of primary photochemistry (Fv/Fm). In order to explore the quantitative relationship between Pn, PAR and Fv/Fm, those parameters were simultaneously measured for different plant species (maize, sunflower, daylily and alfalfa), growth stages and irrigation treatments. Results indicated that the diurnal variation of Pn had no significant correlation with that of Fv/Fm. Mean diurnal values of Pn were linearly correlated with those of Fv/Fm among the different irrigation treatments of alfalfa (p < 0.05), but this linear correlation was not observed among the different species. There was a positive relationship between Pn and Fv/Fm only at midday (12:00 and 14:00) (p < 0.01). A significant linear relationship was observed between the diurnal variation of Pn and PAR × Fv/Fm (p < 0.05), this law was suitable for the different species, and the different growth stages and the different irrigation treatments of the same species. This study confirms that Pn is significantly related to the photochemical energy (PAR × Fv/Fm), the light energy directly used in photochemical reactions of plants. 展开更多
关键词 Net photosynthetic rate PAR FV/FM Relationship
下载PDF
Comparison of the S-, N- or P-Deprivations’ Impacts on Stomatal Conductance, Transpiration and Photosynthetic Rate of Young Maize Leaves 被引量:1
13
作者 Dimitris L. Bouranis Styliani N. Chorianopoulou +4 位作者 Alexandros Dionias Giouli Sofianou Aristotelis Thanasoulas Georgios Liakopoulos Dimosthenis Nikolopoulos 《American Journal of Plant Sciences》 2012年第8期1058-1065,共8页
Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in deprived nutrient solutions against the corresponding control grown under full nutrition;the effects of S-, N- or P-deprivation on lamina... Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in deprived nutrient solutions against the corresponding control grown under full nutrition;the effects of S-, N- or P-deprivation on laminas’ mean stomatal conductance (gs), transpiration rate (E) and photosynthetic rate (A) were monitored, along with the impact on the laminas’ total dry mass (DM), water amount (W), length and surface area (Sa). Furthermore, a time series analysis of each parameter’s response ratios (Rr), i.e. the treatment’s value divided by the corresponding control’s one, was performed. Under S-deprivation, the Rr of laminas’ mean gs, E, and A presented oscillations within a ±15% fluctuation zone, notably the “control” zone, whilst those of laminas’ total DM, water amount, surface area, and length included oscillation during the first days and deviation later on, presenting deviation during d10. Under the N-deprivation conditions all Rr time courses except the A one, included early deviations from the control zone without recovering. The deviation from the control zone appeared at d4. Under P-deprivation, all Rr time courses represented oscillations within the control zone. P-deprivation’s patterns resembled those of S-deprivation. Compared to the one of the S-deprivation, the P-one’s oscillations took place within a broader zone. Linear relationships among the various Rr patterns were found between gs-E, gs-A, E-A, DM-W and DM-Sa. In conclusion, the impact of P-deprivation appeared in an early stage and included an alleviation action, the one of N-deprivation appeared early with no alleviation action, whilst that of S-deprivation appeared later, being rather weaker when compared to the impact of the P-deprivation’s impact. 展开更多
关键词 S-Deprivation N-Deprivation P-Deprivation Hydroponics Zea Mays STOMATAL Conductance TRANSPIRATION rate photosynthetic rate Response Ratios Fluctuation Analysis
下载PDF
Study on Photosynthetic Characteristics of Hybrid Mulberry in Autumn under Herbaceous Cultivation
14
作者 Fangying XU Jinjian YU +2 位作者 Huaqiang DONG Dezhong CHEN Jianzhong TAN 《Agricultural Biotechnology》 CAS 2023年第5期19-21,25,共4页
[Objectives]This study was conducted to clarify the physiological mechanism of growth of hybrid mulberry after autumn cutting in herbaceous cultivation.[Methods]The net photosynthetic rate(Pn),stomatal conductance(Gs)... [Objectives]This study was conducted to clarify the physiological mechanism of growth of hybrid mulberry after autumn cutting in herbaceous cultivation.[Methods]The net photosynthetic rate(Pn),stomatal conductance(Gs),intercellular CO_(2) concentration(Ci)and transpiration rate(Tr)of leaves were measured under different treatment conditions using a Li-6400XT portable photosynthetic measurement system.[Results]After harvest of mulberry shoots in autumn,leaf Pn decreased with the extension of branch and leaf growth time,while Gs,Ci and Tr showed a trend of first increasing and then decreasing.The Pn was affected by factors such as leaf positions,mulberry varieties,cutting,and fertilization,which was manifested by the 6 th to 10 th mature leaves>the 2 nd to 4 th tender leaves,‘Nongsang 14’>hybrid mulberry,intermediate cut>uncut,and normal fertilization>no fertilization,all showing significant differences(P<0.05).Combined with the results of Gs,Ci and Tr measurements,it was found that the changes in leaf Pn were mainly related to non-stomatal factors.Timely cutting and harvesting during summer and autumn could significantly improve the photosynthetic rate of mulberry leaf,which was beneficial for extending the late autumn growth period of hybrid mulberry under herbaceous cultivation.[Conclusions]This study provides a theoretical reference for mulberry shoot harvesting techniques in summer and autumn. 展开更多
关键词 Hybrid mulberry Herbaceous cultivation Harvest of mulberry shoots photosynthetic rate Leaf age
下载PDF
Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas Woodlands
15
作者 Matthew B. Grunstra Oscar W. Van Auken 《American Journal of Plant Sciences》 CAS 2024年第5期329-348,共20页
Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response c... Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response curves at ambient and elevated levels of CO<sub>2</sub> and temperature were measured for D. texana. The A<sub>net</sub> (photosynthetic rate) increased significantly as both light level and CO<sub>2</sub> levels increased but not temperature. The A<sub>max</sub> (maximum photosynthetic rate) of D. texana in full sun at elevated levels of CO<sub>2</sub> was increased for all treatments. Stomatal conductance increased with levels of CO<sub>2</sub> but only if the interaction was removed from the model. Intercellular levels of CO<sub>2</sub> increased with both temperature and CO<sub>2</sub> treatments as did water use efficiency (WUE). Furthermore, light saturation (L<sub>sat</sub>) increased with CO<sub>2</sub> treatments and light compensation (L<sub>cp</sub>) increased with temperature. The dark respiration (R<sub>d</sub>) increased with both temperature and CO<sub>2</sub> treatments. Markov population models suggested D. texana populations would remain ecologically similar in the future. However, sub-canopy light levels and herbivory should be considered when examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herbivory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to be a problem for D. texana juveniles which would allow them to reach the canopy without need of a high light gap and are not prevented by herbivory. Thus, Juniperus/Quercus woodlands will change in the future to woodlands with D. texana a more common species. 展开更多
关键词 Replacement Dynamics Ecological Succession CO2 Concentrations Temperature Levels photosynthetic rates Drought Tolerance HERBIVORY Species Replacement ENCROACHMENT Juniper
下载PDF
QTL analysis of leaf photosynthetic rate and related physiological traits in rice(Oryza sativa L.) 被引量:3
16
作者 TENG Sheng, QIAN Qian, ZENG Dali, Yasufumi Kunihiro, Hiroshi Fujimoto, HUANG Daman, and ZHU Lihuang, Key Lab for Rice Biology, CNRRI, Hangzhou 310006 Inst of Genetics and Development Biology, the Chinese Academy of Sciences, Beijing 100101 +1 位作者 College of Life Sci, Zhejiang Univ, Hangzhou 310029, China Japan International Res Center for Agri Sci, Tsukuba, Japan 《Chinese Rice Research Newsletter》 2002年第3期4-6,共3页
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
关键词 rate DH Oryza sativa L QTL analysis of leaf photosynthetic rate and related physiological traits in rice
下载PDF
Relationship Between Net Photosynthetic Rate of Cassava SC205 and Its Physio-ecological Factors
17
作者 Yong SONG Xuan LIN +2 位作者 Jinhui YANG Yuping DENG Xingyao XIONG 《Agricultural Science & Technology》 CAS 2014年第2期243-247,共5页
[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
关键词 SC205 Net photosynthetic rate Diurnal variation Physiological factors Ecological factors
下载PDF
Preliminary Study on the Photosynthetic Characteristics of Super Hybrid Rice P88S/0389 被引量:4
18
作者 张吉贞 孟卫东 +1 位作者 曹赛 邓晓峰 《Agricultural Science & Technology》 CAS 2008年第4期21-24,38,共5页
[Objective] The aim of this study is to understand the high yield often photosynthetic mechanism of super hybrid rice P88S/0389.[Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and... [Objective] The aim of this study is to understand the high yield often photosynthetic mechanism of super hybrid rice P88S/0389.[Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and Lichtenthaler,and the photosynthetic rate and chlorophyll fluorescence parameters were measured using portable photosynthesis system.Through comparison of above measured indices between P88S/0389 and its parents,the photosynthetic characteristics were obtained.[Result] The pigment content of P88S/0389 lied between their parents,and detailedly was closer to its female parent at earlier growth stage and to its male parent at latter stage,respectively.The Pn,Fv/Fo,Fv/Fm and qP of the flag leaf of P88S/0389 were all higher than those of its parents,while the degradation rates of these parameters were slower than those of its parents.The qN of flag leaf was lower than those of its parents,and the increasing rate of qN of P88S/0389 was also slower than those of its parents,indicating the great heterosis of P88S/0389 to its parents in photosynthetic capacity.The data show that P88S/0389 is endowed with stronger capacities in light energy absorption,transformation and carbon fixation compared to its parents.[Conclusion] The light energy absorbed by hybrid mainly contributes to photochemical reaction,and little for heat dissipation.For ensuring high yield,the rice cultivars selected for production should synchronously possess higher photosynthetic rate and longer high value duration. 展开更多
关键词 NET photosynthetic rate CHLOROPHYLL FLUORESCENCE characteristics CHLOROPHYLL FLUORESCENCE QUENCHING
下载PDF
Photosynthetic Characteristics of Two Superhigh-yield Hybrid Rice 被引量:13
19
作者 王强 张其德 +5 位作者 蒋高明 卢从明 匡廷云 吴爽 李成荃 焦德茂 《Acta Botanica Sinica》 CSCD 2000年第12期1285-1288,共4页
The photosynthetic functions and the sensitivity to photoinhibition were compared between two superhigh_yield hybrid rice (Oryza sativa L.) Liangyoupeijiu and X07S/Zihui 100, the newly developed from two parental line... The photosynthetic functions and the sensitivity to photoinhibition were compared between two superhigh_yield hybrid rice (Oryza sativa L.) Liangyoupeijiu and X07S/Zihui 100, the newly developed from two parental lines and traditional hybrid rice Shanyou 63 developed from three parental lines. The results showed that, as compared to Shanyou 63, the net photosynthetic rate of Liangyoupeijiu and X07S/Zihui 100 was 9.1% and 11.9% higher, the transpiration rate was 37.4% and 31.4% lower, and their water use efficiency was 74.2% and 63.5% higher respectively. After strong light (2 000 μmol photons·m -2 ·s -1 ) treatment for 2 h, the photochemical quantum yield and the photochemical quenching increased by 37.0% and 18.0% respectively in Liangyoupeijiu, 28.3% and 46.2% in X07S/Zihui 100, but decreased a little in Shanyou 63. The non_photochemical quenching decreased in Liangyoupeijiu and X07S/Zihui 100 (about 50%) but increased greatly in Shanyou 63 (about 50%). Better photosynthetic functions, higher water use efficiency and stronger resistance to photoinhibition, may be the physiological basis for the super high_yield of the two hybrid rice under study. 展开更多
关键词 superhigh-yield hybrid rice net photosynthetic rate water use efficiency PHOTOINHIBITION fluorescence induction kinetics parameters
下载PDF
Seasonal Changes in Photosynthetic Characteristics of Ammopiptanthus mongolicus 被引量:43
20
作者 李文瑞 冯金朝 +2 位作者 江天然 张立新 刘新民 《Acta Botanica Sinica》 CSCD 1999年第2期190-193,共4页
Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductan... Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation. 展开更多
关键词 Net photosynthetic rate Stomatal conductance Intercellular CO2 concentration Stomatal limitation value RUBISCO Electron transport activity
下载PDF
上一页 1 2 179 下一页 到第
使用帮助 返回顶部