The seeds of soybean cv. Aldana and spring wheat cv. Torka were soaked for 24 h in solution of zearalenone [ZEN, 2,4-dihydroxy-6-(10-hydroxy-6-oxo-trans-1-undecenyl)-benzonic acid lactone, 4 mg dm-3] and then they were sown in the pot experiment in an open vegetation hall. The after-effects of ZEN on growth of plants, net photosynthetic (PN) and transpiration (E) rates, stomatal conductance (gs), photochemical efficiency of photosystem II (PSII) and on final seeds yield, were determined. A significant increase of seeds yield was revealed in plants of both cultivars i.e. by 22% and 19% of seed (grain) number and by 28 and 24% of seed (grain) mass, in soybean and in wheat, respectively. The photosynthetic rate (PN) was stimulated during the juvenile and final phase by about 13.6% (average) in soybean plants. During other developmental stages, assimilation of CO2 was retarded. The response of CO2 assimilation in wheat plants was less pronounced as compared to that in soybean, but an increase of PN by over 24% near the final stage of development was observed. The quantum yield of PSII electron transport (ΦPSII) in soybean plants was changed after the treatment of seeds by ZEN similarly as for the rate of CO2, whereas in wheat it continued to gradually increase i.e. during the whole growth period. Changes of ΦPSII both in soybean and in wheat plants, as the response to ZEN treatment, were accompanied with an increase in the efficiency of changes occurring within the antenna (Fv'/Fm') as well as within centres of photochemical reactions (qp). The conclusion is that ZEN can affect plant growth and development in many ways, as well as in the status and functioning of the photosynthetical apparatus. Some of the effects can be very longlasting, as e.g. stimulation of production of seed yield in response to treatment of seeds with this substance. and J. Kościelniak ... [et al.].
The physiological response of plants to triple foliar biofertilization with cyanobacteria and green algae under the conditions of limited use of chemical fertilizers was investigated. Triple foliar biofertilization with intact cells of Microcystis aeruginosa MKR 0105, Anabaena sp. PCC 7120, and Chlorella sp. significantly enhanced physiological performance and growth of plants fertilized with a synthetic fertilizer YaraMila Complex (1.0, 0.5, and 0.0 g per plant). This biofertilization increased the stability of cytomembranes, chlorophyll content, intensity of net photosynthesis, transpiration, stomatal conductance, and decreased intercellular CO2 concentration. Applied monocultures augmented the quantity of N, P, K in plants, the activity of enzymes, such as dehydrogenases, RNase, acid or alkaline phosphatase and nitrate reductase. They also improved the growth of willow plants. This study revealed that the applied nontoxic cyanobacteria and green algae monocultures have a very useful potential to increase production of willow, and needed doses of chemical fertilizers can be reduced., M. Grzesik, Z. Romanowska-Duda, H. M. Kalaji., and Obsahuje bibliografii
Water is a limited resource and is likely to become even more restricted with climate change. The aim of this study was to evaluate the effect of humic acid (HA) applications on photosynthesis efficiency of rapeseed plants under different watering conditions. Water stress strongly increased electron transport flux, probability that trapped excitation can move an electron into the electron transport chain beyond QA, and quantum yield of reduction of end electron acceptors at the PSI acceptor side. Application of HA decreased the values of these parameters to be similar to those of non-stress conditions. We found that, the application of HA improved plants net photosynthesis under water stress via increasing the rate of gas exchange and electron transport flux in plants., R. Lotfi, H. M. Kalaji, G. R. Valizadeh, E. Khalilvand Behrozyar, A. Hemati, P. Gharavi-Kochebagh, A. Ghassemi., and Obsahuje bibliografii
The response of some photosynthetic parameters (CO2 assimilation, transpiration rate, stomatal conductance, intercellular CO2 concentration, water-use efficiency, and chlorophyll content), shoot development, and the morphological features of the root system to differentiated conditions of nitrogen supply was tested in festulolium (Festulolium braunii K. Richert A. Camus) varieties (Felopa and Sulino). Nitrogen fertilization with no nitrogen added
[0 g(N)], single dosage [0.23 g(N)], and double dosage [0.46 g(N)] per pot and per year was applied. Lack of nitrogen resulted in formation of longer and finer roots and lowered chlorophyll content, CO₂ assimilation, and water-use efficiency, resulting in lower dry matter accumulation. Application of both dosages of nitrogen resulted in improved aboveground features, while root features were enhanced without nitrogen fertilization. Dependence between physiological parameters and morphological traits was significant and positively correlated in the case of the aboveground parts of plants and negatively correlated to the belowground parts., G. Mastalerczuk, B. Borawska-Jarmułowicz, H. M. Kalaji, P. Dąbrowski, J. Paderewski., and Obsahuje bibliografii
Increasing human and industrial activities lead to heavy metal pollution. Heavy metal chromium (Cr) is considered to be a serious environmental contaminant for the biota. Phytotoxic effects of Cr were studied in wheat plants. Growth parameters were largely inhibited as a result of disturbances in the plant cell metabolism in response to Cr toxicity. Chromium toxicity led to decline in a number of active reaction centres of PSII, rate of electron transport, and change in PSII heterogeneity. Chromium did not cause any change in heterogeneity of the reducing side. A significant change in antenna size heterogeneity of PSII occurred in response to Cr toxicity. Chromium seems to have extensive effects on the light harvesting complex of PSII., S. Mathur, H. M. Kalaji, A. Jajoo., and Obsahuje seznam literatury
The study examined photosynthetic efficiency of two barley landraces (cvs. Arabi Abiad and Arabi Aswad) through a prompt fluorescence technique under influence of 14 different abiotic stress factors. The difference in the behavior of photosynthetic parameters under the same stress factor in-between cv. Arabi Abiad and cv. Arabi Aswad indicated different mechanisms of tolerance and strategies for the conversion of light energy into chemical energy for both the landraces. This study confirmed the suitability of some chlorophyll fluorescence parameters as reliable biomarkers for screening the plants at the level of photosynthetic apparatus., H. M. Kalaji, A. Rastogi, M. Živčák, M. Brestic, A. Daszkowska-Golec, K. Sitko, K. Y. Alsharafa, R. Lotfi, P. Stypiński, I. A. Samborska, M. D. Cetner., and Obsahuje bibliografii
The aim of this work was to determine two types of photosynthetic water-use efficiency in order to examine their utility as selection criteria for tolerance of energy crops to soil water deficit. Furthermore, effects of crop cultivation on soil water content and storage were investigated. Seven energy crops were examined: miscanthus, prairie cordgrass, willow, thorn-free rose, Virginia mallow, Bohemian knotweed, and topinambour. The highest values of instantaneous (WUE) and intrinsic (WUEi) water-use efficiencies were found for miscanthus and prairie cordgrass. The reduction of WUE and/or WUEi was caused mainly by a rapid rise in the transpiration rate and a greater stomatal conductance, respectively. Principal component analysis showed that neither WUE nor WUEi could be recommended as universal selection criteria for the drought tolerance in different energy crops. The proper localization of soil with a good supply of water is most the important condition for energy crop plantations., S. Podlaski, S. Pietkiewicz, D. Chołuj, T. Horaczek, G. Wiśniewski, D. Gozdowski, H. M. Kalaji., and Obsahuje bibliografii