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1172. Influence of phosphorus and endomycorrhiza (Glomus intraradices) on gas exchange and plant growth of chile ancho pepper (Capsicum annuum L. cv. San Luis)
- Creator:
- Aguilera-Gomez, L., Davies, Jr., F. T., Olalde-Portugal, V., Duray, S. A., and Phavaphutanon, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fruit, internal CO2 concentration, leaf area ratio, leaf number and area, net photosynthetic rate, phosphorus use efficiency, root, shoot, and stomatal conductance
- Language:
- Multiple languages
- Description:
- Seedlings of chile ancho pepper were grown in pots containing a pasteurized mixture of sand and a low phosphorus (P) sandy loam soil, and either inoculated (VAM) or not inoculated (NVAM) with the endomycorrhizal fungus Glomus intraradices. Long Ashton nutrient solution (LANS) was modified to supply P to the seedlings at 0, 11, and 44 g(P) m-3 (P0, P11, P44, respectively). Low P depressed net photosynthetic rate (PN), stomatal conductance (gs), phosphorus use efficiency (PN/P), and internal CO2 concentration (Ci). The mycorrhiza alleviated low P effects by increasing PN, gs, PN/P, and decreasing Ci. At P0, Ci of NVAM plants was equal to or higher than that of VAM plants, suggesting nonstomatal inhibition of photosynthesis. Gas exchange of VAM plants at P0 was similar to that of NVAM plants at P11. Endomycorrhiza increased leaf number, leaf area, shoot, root and fruit mass at P0 and P11 compared to NVAM plants. Reproductive growth was enhanced by 450 % in mycorrhizal plants at P44. Root colonization (arbuscules, vesicles, internal and extraradical hyphae development) was higher at lower P concentrations, while sporulation was unaffected. The enhanced growth and gas exchange of mycorrhizal plants was in part due to greater uptake of P and greater extraradical hyphae development. and L. Aguilera-Gomez ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1173. Influence of phosphorus and nitrogen on photosynthetic parameters and growth in Vicia faba L.
- Creator:
- Jia, Y. and Gray, V. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carboxylation efficiency, intercellular CO2 concentration, leaf area, nitrogen use efficiency, photon unsaturated photosynthetic rate, quantum yield efficiency, root, and stem
- Language:
- Multiple languages
- Description:
- The influence of phosphorus (P) and nitrogen (N) supply on biomass, leaf area, photon saturated photosynthetic rate (Pmax), quantum yield efficiency (α), intercellular CO2 concentration (Ci), and carboxylation efficiency (CE) was investigated in Vicia faba. The influence of P on N accumulation, biomass, and leaf area production was also investigated. An increase in P supply was consistently associated with an increase in N accumulation and N productivity in terms of biomass and leaf area production. Furthermore, P increased the photosynthetic N use efficiency (NUE) in terms of Pmax and α. An increase in P supply was also associated with an increase in CE and a decrease in Ci. Under variable daily meteorological conditions specific leaf nitrogen content (NL), specific leaf phosphorus content (PL), specific leaf area (δL), root mass fraction (Rf), Pmax, and α remained constant for a given N and P supply. A monotonic decline in the steady-state value of Rf occurred with increasing N supply. δL increased with increasing N supply or with increasing NL. We tested also the hypothesis that P supply positively affects both N demand and photosynthetic NUE by influencing the upper limit of the asymptotic values for Pmax and CE, and the lower limit for Ci in response to increasing N. and Y. Jia, V. M. Gray.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1174. Influence of phosphorus on gas exchange and plant growth of two morphologically distinct types of Capsicum annuum
- Creator:
- Davies, F. T., Duray, S. A., Phavaphutanon, L., and Stahl, R. S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Multiple languages
- Description:
- Tolerance to phosphorus stress was studied in Capsicum annuum L. Chile ancho cv. San Luis and bell pepper cv. Jupiter plants. Plants were fertilized weekly with Long-Ashton nutrient solution (LANS) modified to supply 0, 11, 22, 44, 66, or 88 g(P) m-3 (P0, P11, P22, P44, P66, P88). Phosphorus stress occurred in both cultivars at P0 and P11, with reduced plant growth and development. At P0, the lowest percentage of total biomass was directed toward reproductive growth. The root/shoot ratio was greatest at P0, reflecting greater dry matter partitioning to the root system. Growth of 'San Luis' was more sensitive to phosphorus stress than 'Jupiter'. A greater percentage of total biomass was directed towards reproductive growth in 'Jupiter' than 'San Luis'. Increasing P nutrition elevated leaf tissue P in both cultivars with highest leaf tissue P at P88. There were no differences in tissue P between P0 and P11 'San Luis' plants, whereas P0 'Jupiter' plants had the lowest tissue P. Low P-plants generally had the highest tissue N and lowest S, Mn, and B. In both cultivars, gas exchange was lowest at P0, as indicated by reduced stomatal conductance (gs) and net photosynthetic rate (PN). Internal CO2 concentration and leaf-to-air vapor pressure difference (VPD) were generally highest with P-stressed plants. Phosphorus use efficiency, as indicated by PN per unit of leaf tissue P concentration (PN/P), was highest at P11. Generally, no P treatments exceeded the gas exchange levels obtained by P44 (full strength LANS) plants. Both PN and gs declined during reproductive growth in 'San Luis', which fruits more rapidly than 'Jupiter', whereas no reduction in gas exchange occurred with 'Jupiter'. and F. T. Davies ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1175. Influence of potassium deficiency on photosynthesis, chlorophyll content, and chloroplast ultrastructure of cotton plants
- Creator:
- Zhao, Duli, Oosterhuis, D. M., and Bednarz, C. W.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Gossypium hirsutum, intercellular CO2 concentration, net photosynthetic rate, non-structural saccharides, photosynthate translocation, stomata conductance, and transpiration rate
- Language:
- Multiple languages
- Description:
- In cotton (Gossypium hirsutum L.) grown in controlled-environment growth chamber the effects of K deficiency during floral bud development on leaf photosynthesis, contents of chlorophyll (Chl) and nonstructural saccharides, leaf anatomy, chloroplast ultrastructure, and plant dry matter accumulation were studied. After cotton plants received 35-d K-free nutrient solution at the early square stage, net photosynthetic rate (PN) of the uppermost fully expanded main-stem leaves was only 23 % of the control plants receiving a full K supply. Decreased leaf PN of K-deficient cotton was mainly associated with dramatically low Chl content, poor chloroplast ultrastructure, and restricted saccharide translocation, rather than limited stomata conductance in K-deficient leaves. Accumulation of sucrose in leaves of K-deficient plants might be associated with reduced entry of sucrose into the transport pool or decreased phloem loading. K deficiency during squaring also dramatically reduced leaf area and dry matter accumulation, and affected assimilate partitioning among plant tissues. and Duli Zhao, D. M. Oosterhuis, C. W. Bednarz.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1176. Influence of potassium nutrition on gas exchange characteristics and water relations in cotton (Gossypium hirsutum L.)
- Creator:
- Pervez, H., Ashraf, M., and Makhdum, M. I.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- net photosynthetic rate, osmotic potential, pressure potential, stomatal conductance, transpiration ate, and water-use efficiency
- Language:
- Multiple languages
- Description:
- The effects of potassium nutrition [0, 6.25, 12.50, 25.00 g(K) m-2 of K2SO4 or KCl] on gas exchange characteristics and water relations in four cultivars (CIM-448, CIM-1100, Karishma, S-12) of cotton were assessed under an arid environment. Net photosynthetic rate (PN) and transpiration rate (E) increased with increased K supply. The leaf pressure potential (Ψp) increased significantly by the addition of 25.00 g(K) m-2 compared to zero K level. The water use efficiency (PN/E) was improved by 24.6 % under the highest K dose compared to zero K. There were positive correlations (0.99**, 0.98**, 0.95**, 0.97**) between K-doses and PN, E, Ψp, and PN/E, respectively. and H. Pervez, M. Ashraf, M. I. Makhdum.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1177. Influence of salinity on Na+ and K+ accumulation, and gas exchange in Avicennia germinans
- Creator:
- Suárez, N. and Medina, E.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- growth, leaf water relations, net photosynthetic rate, potassium, and stomatal conductance
- Language:
- Multiple languages
- Description:
- We analysed plant growth, ion accumulation, leaf water relations, and gas exchange of Avicennia germinans (L.) L. subjected to a long-term, controlled salinity gradient from 0 to 55 ‰. Growth and leaf area were affected by salinity higher than 10 ‰. As salinity increased, the predawn leaf water potential (Ψw) and leaf osmotic potential (Ψs) decreased. Leaf Ψw was at least -0.32 MPa lower than the Ψw of solution. Na+ and K+ ions explained about 78 % of decrease in Ψs. K+ tissue water concentration decreased by more than 60 % in all salinity treatments as compared with those grown at 0 ‰. Inversely, Na+ concentration in tissue water increased with nutrient solution salinity. The maximum net photosynthetic rate (PN) and stomatal conductance (gs) decreased by 68 and 82 %, respectively, as salinity increased from 0 to 55 ‰; the intercellular CO2 concentration (Ci) followed the same trend. The PN as a function of Ci showed that both the initial linear slope and upper plateau of the PN vs. Ci curve were markedly affected by high salinity (40 and 55 ‰). and N. Suárez, E. Medina.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1178. Influence of shading inclined tubular photobioreactor surfaces on biomass productivity of C. sorokiniana
- Creator:
- Ugwu, C. U. and Aoyagi, H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- algae, carotenoids, chlorophyll, flashing radiation, and intermittent radiation
- Language:
- Multiple languages
- Description:
- Shading of the tubular photobioreactor (PBR) surfaces that diminished solar irradiance to 70 % led to higher biomass productivity and greater accumulation of total chlorophyll and carotenoids compared to the values obtained when the PBR was completely exposed to full sunlight. and C. U. Ugwu, H. Aoyagi.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1179. Influence of temperature on the effects of artificially enhanced UV-B radiation on aquatic bryophytes under laboratory conditions
- Creator:
- Nuñez-Olivera, E., Martínez-Abaigar, J., Tomás, R., Beaucourt, N., and Arróniz-Crespo, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carotenoids, chlorophylls, Fontinalis, Jungermannia, net photosynthetic rate, pheopigments, and respiration
- Language:
- Multiple languages
- Description:
- We examined, under laboratory conditions, the influence of temperature (2 °C vs. 10 °C) on the physiological responses of two aquatic bryophytes from a mountain stream to artificially enhanced UV-B radiation for 82 d. These organisms may be exposed naturally to relatively low temperatures and high levels of UV-B radiation, and this combination is believed to increase the adverse effects of UV-B radiation. In the moss Fontinalis antipyretica, UV-B-treated samples showed severe physiological damages, including significant decreases in chlorophyll (Chl) and carotenoid (Car) contents, Chl a/b and Chl/phaeopigment ratios, Chl a fluorescence parameters Fv/Fm and ΦPS2, electron transport rate (ETRmax), and growth. In the liverwort Jungermannia cordifolia, UV-B radiation hardly caused any physiological change except for growth reduction. Thus, this liverwort seemed to be more tolerant to UV-B radiation than the moss under the specific experimental conditions used, maybe partly due to the accumulation of UV-B absorbing compounds. The influence of temperature on the effects of UV-B radiation depended on the species: the higher the UV-B tolerance, the lower the influence of temperature. Also, different physiological variables showed varied responses to this influence. Particularly, the lower temperature used in our study enhanced the adverse effects of UV-B radiation on important physiological variables such as Fv/Fm, growth, and Chl/phaeopigment ratios in the UV-B-sensitive F. antipyretica, but not in the more UV-B-tolerant J. cordifolia. Thus, the adverse effects of cold and UV-B radiation were apparently additive in the moss, but this additiveness was lacking in the liverwort. The Principal Components Analyses (PCA) conducted for both species with the physiological data obtained after 36 and 82 d of culture confirmed the above results. Under natural conditions, the relatively high water temperatures in summer might facilitate the acclimation of aquatic bryophytes from mountain streams to high levels of UV-B radiation. This may be relevant to predict the consequences of concomitant global warming and increasing UV-B radiation. and E. Nuñez-Olivera ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1180. Influence of the degree of solvent impurity on the spectrophotometric determination of chlorophylls in 80 % aqueous acetone and dimethyl formamide. Application to non-abrasive extraction of leaves of Citrus aurantium
- Creator:
- García, A. L. and Nicolás, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Multiple languages
- Description:
- Chlorophyll (Chl) a and Chl b absorbances were determined in extracts from leaves of Citrus aurantium L. using the solvents diethyl ether (100 %), buffered 80 % aqueous acetone, and N,N'-dimethyl formamide (DMF) (99.83 %). The respective standard deviations (σ) and coefficients of variability (CV) were used to establish the errors obtained when using impure solvents. Buffered 80 % aqueous acetone gave an error of 2.1 % for Chl a and 7.1 % for Chl b, while DMF gave errors of 3.5 and 6.7 %, respectively. For current Chl determination we propose a non-abrasive method, which extracts 15 leaf discs (diameter 6 mm) with 10 cm3 of buffered 80 % aqueous acetone or DMF in hermetically sealed flasks during 24 h in darkness at 4 °C. and A. L. García, N. Nicolás.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public