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12. Effect of Rhizobium sp. inoculation on N2-fixing and photosynthetic activities of two cowpea [Vigna unguiculata (L.) Walp.] genotypes
- Creator:
- Lippi, D., de Paolis, M. R., Osmi, M., Pietrini, F., Pietrosanti, T., Villani, M. C., and Massacci, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acetylene reduction, leaf area, monocarpic senescence, plant octogeny, and ureides
- Language:
- Multiple languages
- Description:
- Time course of symbiotic N2-fixing and photosynthetic activities during vegetative growth from 30 d after plantation until pod set was measured in the CB5 and 7964 cowpea [Vigna unguiculata (L.) Walp.] genotypes of contrasting senescence traits. At emergence, seedlings were inoculated with a "non-cowpea miscellany" Rhizobium strain generally used to inoculate Cicer arietinum. Maximum N2-fixing activity occurred in inoculated CB5 and 7964 plants about 54 and 68 d after plantation, respectively. A similar temporal shift of maximum was found for net photosynthetic rate (PN), confirming a good coordination between the two processes. A higher PN was found from the first measurements in inoculated plants of both genotypes as compared with uninoculated plants. Apparently, the maximum activity of both N2-fixation and PN was timed to occur at a particular stage of plant ontogeny correlating the high N supply with the high N demand by the plant. Rhizobium inoculation did not significantly affect partitioning coefficients of biomass to various plant organs but extended leaf longevity by about 10 d in the CB5 genotype, retarding thus the monocarpic senescence. and D. Lippi ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
13. Effect of triacontanol in flooded Erythrina variegata seedlings. 1. Changes in growth, photosynthetic pigments and biomass productivity
- Creator:
- Muthuchelian, K., Murugan, C., Harigovindan, R., Nedunchezhian, N., and Kulandaveilu, G.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- carotenoids, specific leaf mass, saccharides, relative growth rate, proteins, plant height, leaf area index, leaf area, and chlorophyll
- Language:
- Multiple languages
- Description:
- Seedlings of Erythrina variegata Lam. exposed to flooding for 10 d showed significant reduction in height, growth rates (leaf area in plant, leaf area index, relative growth rate, and specific leaf mass), biomass, chlorophyli (Chl) and carotenoid contents, and thylakoid membrane organization. Application of triacontanol partially compensated these effects and promoted height, biomass and Chl content. Starch and sugar contents were significantly higher in leaves of flooded seedlings.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14. Effects of cadmium and gibberellin on growth and photosynthesis of Glycine max
- Creator:
- Ghorbanli, M., Kaveh, S. Hadad, and Sepehr, M. Farzami
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, CO2 compensation concentration, dry matter production, growth rate, leaf area, net assimilation rate, root, shoot, and starch
- Language:
- Multiple languages
- Description:
- The effects of 0, 2.5, 5.0, and 10.0 mg(Cd2+) m-3 [Cd(NO3)2×4 H2O] and 0 and 10.0 mg m-3 gibberellin on certain parameters of photosynthesis and growth in soybean (Glycine max L. cv. Pershing) plants were studied. With increasing Cd2+ concentration in the Hoagland nutrient solution, the contents of chlorophyll and CO2 compensation concentration decreased. The addition of 10 mg m-3 gibberellin reduced the negative effects of Cd2+ in shoot and root growth. With increasing of Cd2+ concentration in the culture medium, the dry matter production in both the roots and shoots decreased as shown by the decline in growth rate (PGR), net assimilation rate (NAR), and leaf area ratio. The addition of gibberellin caused a partial elimination of the Cd effects on the roots and shoots and the PGR and NAR and it increased leaf area and length of stem. and M. Ghorbanli, S. Hadad Kaveh, M. Farzami Sepehr.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15. Effects of elevated CO2 and moisture stress on Brassica juncea
- Creator:
- Rabha, B. K. and Uprety, D. C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, dry mass, leaf area, leaf water potential, open-top chamber, relative water content, seed mass and yield, stomatal conductance, transpiration, and water potential
- Language:
- Multiple languages
- Description:
- The interactive effect of elevated CO2 (EC) and moisture stress (MS) on Brassica juncea cv. Pusa Bold was studied using open-top chambers. The EC markedly increased net photosynthetic rate and internal CO2 concentration and reduced variable and maximal chlorophyll fluorescence. Under MS, EC increased water potential and relative water content, and reduced transpiration rate. The greater allocation of biomass to the roots, which serve as a strong sink for assimilated carbon under EC, helped in better root growth. and B. K. Rabha, D. C. Uprety.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
16. Effects of nitrogen supply restriction on gas exchange and photosystem 2 function in flag leaves of a traditional low-yield cultivar and a recently improved high-yield cultivar of rice (Oryza sativa L.)
- Creator:
- Kumagai, E., Araki, T., and Kubota, F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, chlorophyll fluorescence, dry matter production, leaf area, mesophyll conductance, net photosynthetic rate, non-photochemical quenching, quantum yield, ribulose-1,5-bisphosphate carboxylase, oxygenase, and stomatal conductance
- Language:
- Multiple languages
- Description:
- The effects of nitrogen (N) supply restriction on the CO2 assimilation and photosystem 2 (PS2) function of flag leaves were compared between two contrastive Japanese rice cultivars, a low-yield cultivar released one century ago, cv. Shirobeniya (SRB), and a recently improved high-yield cultivar, cv. Akenohoshi (AKN). Both cultivars were solution-cultured at four N supply levels from N4 (control) to N1 (the lowest). With a reduction in N-supply, contents of N (LNC), ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO), and chlorophyll (Chl) in flag leaves decreased in both cultivars. In parallel with this, the net photosynthetic rate (PN), mesophyll conductance (g m), and stomatal conductance (gs) decreased. PN was more dominantly restricted by gm than gs. The values of PN, gm, and RuBPCO content were larger in AKN than SRB at the four N supply levels. The content of Chl greatly decreased with N deficiency, but the reduction in the maximum quantum yield of PS2 was relatively small. Quantum yield of PS2 (ΦPS2) decreased with N deficiency, and its significant cultivar difference was observed between the two cultivars at N1: a high value was found in AKN. The content ratio of Chl/RuBPCO was also significantly low in AKN. The low Chl/RuBPCO is one of the reasons why AKN maintained a comparatively high PN and ΦPS2 at N deficiency. The adequate ratio of N distribution between Chl and RuBPCO is the important prerequisite for the efficient and sustainable photosynthesis in a flag leaf of rice plant under low N-input. and E. Kumagai, T. Araki, F. Kubota.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17. Effects of rhizobia inoculation and nitrogen fertilization on photosynthetic physiology of soybean
- Creator:
- Zhou, X.-J., Liang, Y., Chen, H., Shen, S.-H., and Jing, Y.-X.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- biological nitrogen fixation, biomass, carboxylation efficiency, carotenoids, chlorophyll fluorescence, Glycine max, intercellular CO2 concentration, leaf area, stomatal conductance, and quantum yield
- Language:
- Multiple languages
- Description:
- Plant growth, contents of photosynthetic pigments, photosynthetic gas exchange, and chlorophyll (Chl) fluorescence in soybean [Glycine max (L.) Merr. cv. Heinong37] were investigated after it was inoculated with Sinorhizobium fredii USDA191 or treated with 5 mM (NH4)2SO4 (N5) and 30 mM (NH4)2SO4 (N30), respectively. In the plants following N5 fertilization, not only plant biomass, leaf area, and Chl content, but also net photosynthetic rate (PN), stomatal conductance (gs), carboxylation efficiency (CE), maximum photochemical efficiency (Fv/Fm) of photosystem 2 (PS2), and quantum yield of PS2 (ΦPS2) were markedly improved as compared with the control plants. There were also positive effects on plant growth and plant photosynthesis after rhizobia inoculation, but the effects were much less than those of N5 fertilization. For N30 plants there were no significant positive effects on plant growth and photosynthetic capacity. Plant biomass, PN, and gs were similar to those of N-limited (control) plants. ΦPS2 and photochemical quenching (qP) were obviously declined while content of carotenoids and non-photochemical quenching (qN) were significantly enhanced in N30 treated plants. This indicated that excess N supply may cause some negative effects on soybean plants. and X.-J. Zhou ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
18. Effects of water stress and nitrogen supply on leaf gas exchange and fluorescence parameters of Sophora davidii seedlings
- Creator:
- Wu, F. Z., Bao, W. K., Li, F. L., and Wu, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- adaptation, chlorophyll fluorescence, intercellular CO2 concentration, leaf area, net photosynthetic rate, respiration rate, specific leaf area, stomatal conductance, and water use efficiency
- Language:
- Multiple languages
- Description:
- Two-month-old seedlings of Sophora davidii were subjected to a randomized complete block design with three water (80, 40, and 20 % of water field capacity, i.e. FC80, FC40, and FC20) and three N supply [N0: 0, Nl: 92 and Nh: 184 mg(N) kg-1(soil)] regimes. Water stress produced decreased leaf area (LA) and photosynthetic pigment contents, inhibited photosynthetic efficiency, and induced photodamage in photosystem 2 (PS2), but increased specific leaf area (SLA). The decreased net photosynthetic rate (PN) under medium water stress (FC40) compared to control (FC80) might result from stomatal limitations, but the decreased PN under severe water deficit (FC20) might be attributed to non-stomatal limitations. On the other hand, N supply could improve photosynthetic capacity by increasing LA and photosynthetic pigment contents, and enhancing photosynthetic efficiency under water deficit. Moreover, N supply did a little in alleviating photodamages to PS2 caused by water stress. Hence water stress was the primary limitation in photosynthetic processes of S. davidii seedlings, while the photosynthetic characters of seedlings exhibited positive responses to N supply. Appropriate N supply is recommended to improve photosynthetic efficiency and alleviate photodamage under water stress. and F. Z. Wu ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
19. Excess irradiance causes early symptoms of senescence during leaf expansion in photoautotrophically in vitro grown tobacco plants
- Creator:
- Radochová, B. and Tichá, I.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll a fluorescence, leaf area, leaf dry mass, leaf ontogeny, net oxygen evolution rate, Nicotiana, and photosynthesis
- Language:
- Multiple languages
- Description:
- Photosynthetic parameters, growth, and pigment contents were determined during expansion of the fourth leaf of in vitro photoautotrophically cultured Nicotiana tabacum L. plants at three irradiances [photosynthetically active radiation (400-700 nm): low, LI 60 µmol m-2 s-1; middle, MI 180 µmol m-2 s-1; and high, HI 270 µmol m-2 s-1]. During leaf expansion, several symptoms usually accompanying leaf senescence appeared very early in HI and then in MI plants. Symptoms of senescence in developing leaves were: decreasing chlorophyll (Chl) a+b content and Chl a/b ratio, decreasing both maximum (FV/FM) and actual (ΦPS2) photochemical efficiency of photosystem 2, and increasing non-photochemical quenching. Nevertheless, net photosynthetic oxygen evolution rate (PN) did not decrease consistently with decrease in Chl content, but exhibited a typical ontogenetic course with gradual increase. PN reached its maximum before full leaf expansion and then tended to decline. Thus excess irradiance during in vitro cultivation did not cause early start of leaf senescence, but impaired photosynthetic performance and Chl content in leaves and changed their typical ontogenetic course. and B. Radochová, I. Tichá.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
20. Gas exchange of in vitro and ex vitro grown grapevine plants
- Creator:
- Slavtcheva, T. and Dimitrova, V.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acclimation, dark respiration rate, fresh mass, leaf area, net photosynthetic rate, shoot and root lengths, shoot node number, transpiration rate, and Vitis vinifera L.
- Language:
- Multiple languages
- Description:
- Net photosynthetic rate (PN) and dark respiration rate (RD) were measured in Vitis vinifera L. cvs. Dimiat 4/24 (23rd subculture), Dimiat 4/38 (22nd subculture), and Italian Riesling 3/47 (22nd subculture) on days 3, 2, and 1 (1st series) before transfer from the in vitro culture and on days 14, 15, 16 (2nd series) and 28, 29, 30 (3rd series) after the transfer. PN of in vitro and ex vitro plants was strongly affected by irradiance. PN and RD of in vitro plantlets were lower and transpiration rate (E) was higher compared to those of ex vitro plantlets. PN, RD, and E changed in the course of acclimation. and T. Slavtcheva, V. Dimitrova.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public