Search

Start Over Subject jilm

1. Effects of NaCl stress on the growth and photosynthetic characteristics of Ulmus pumila L. seedlings in sand culture

Creator:
Feng, Z. T., Deng, Y. Q., Fan, H., Sun, Q. J., Sui, N., and Wang, B. S.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, jilm, chlorid sodný, photosynthesis, Ulmus, sodium chloride, chlorophyll fluorescence, gas exchange, elm, growth, salt stress, sodium ion, NaCl, Ulmus pumila, 2, and 581
Language:
Multiple languages
Description:
The effects of NaCl stress on the growth and photosynthetic characters of Ulmus pumila L. seedlings were investigated under sand culture condition. With increasing NaCl concentration, main stem height, branch number, leaf number, and leaf area declined, while Na+ content and the Na+/K+ ratio in both expanded and expanding leaves increased. Na+ content was significantly higher in expanded leaves than in those just expanding. Chlorophyll (Chl) a and Chl b contents declined as NaCl concentration increased. The net photosynthetic rate, intercellular CO2 concentration, stomatal conductance, and transpiration rate also declined, but stomatal limitation value increased as NaCl concentration increased. Both the maximal quantum yield of PSII photochemistry and the effective quantum yield of PSII photochemistry declined as NaCl concentration rose. These results suggest that the accumulation of Na+ in already expanded leaves might reduce damage to the expanding leaves and help U. pumila endure high salinity. The reduced photosynthesis in response to salt stress was mainly caused by stomatal limitation., Z. T. Feng, Y. Q. Deng, H. Fan, Q. J. Sun, N. Sui, B. S. Wang., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. The effect of galling aphids feeding on photosynthesis photochemistry of elm trees (Ulmus sp.)

Creator:
Kmieć, K., Rubinowska, K., Michałek, W., and Sytykiewicz, H.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, mšice, jilm, photosynthesis, aphids, Ulmus, biotic stress, Eriosomatinae, fluorescence parameters, host plant response, 2, and 581
Language:
Multiple languages
Description:
Changes of chlorophyll (Chl) a fluorescence and photosynthetic pigment contents were analysed in galled leaves (visibly damaged and undamaged parts) and intact leaves. The values of minimal fluorescence of the dark-adapted state, maximal quantum yield of PSII photochemistry, effective quantum yield of PSII photochemical conversion, and photochemical quenching coefficient decreased in Ulmus pumila L. leaves galled by Tetraneura ulmi (L.) and in U. glabra Huds. galled by Eriosoma ulmi (L.). Colopha compressa (Koch.) feeding affected these parameters only in damaged parts of U. laevis Pall. galled leaves. The increasing number of T. ulmi galls progressively decreased photosynthetic performance. In gall tissues of all analysed aphid species, the lowest photosynthetic pigment content was found, indicating that the photosynthetic capacity must have been low in galls. Significant reduction of Chl and carotenoid contents were observed in damaged and undamaged portions of galled leaves only in the case of T. ulmi feeding., K. Kmieć, K. Rubinowska, W. Michałek, H. Sytykiewicz., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public