The review is devoted to the outstanding contributions to the path of carbon in photosynthesis by Professor Emeritus Andrew A. Benson, on the occasion of his death at the age of 97, on January 16, 2015. Benson is the legendary co-discoverer of the photosynthetic reductive pentose phosphate cycle, known to every student of photosynthesis as the Benson-Bassham-Calvin cycle. This pathway evolved into the dominant assimilation mechanism for atmospheric carbon into metabolites. The fundamental ecological and biochemical optimization and evolutionary stability of this mechanism unfolded elegantly in Benson’s hands, as he was the first to recognize the building blocks for the synthesis of essential organic compounds that satisfy the energetic needs and demands of most life forms. Photosynthetic carbon metabolism together with other energy and oxidative reactions and secondary biosynthetic processes are critical for the formation of organic matter; and, thereby, the Benson-Bassham-Calvin cycle ensures maintenance of the biosphere., K. Biel, I. Fomina., and Obsahuje bibliografii
Benzoxazolin-2-(3H)-one (BOA) has been tested in many plants species, but not in soybean (Glycine max). Thus, a hydroponic experiment was conducted to assess the effects of BOA on soybean photosynthesis. BOA reduced net photosynthetic rate, stomatal conductance, and effective quantum yield of PSII photochemistry without affecting intercellular CO2 concentration or maximal quantum yield of PSII photochemistry. Results revealed that the reduced stomatal conductance restricted entry of CO2 into substomatal spaces, thus limiting CO2 assimilation. No change found in intercellular CO2 concentration and reduced effective quantum yield of PSII photochemistry revealed that CO2 was not efficiently consumed by the plants. Our data indicated that the effects of BOA on soybean photosynthesis occurred due to the reduced stomatal conductance and decreased efficiency of carbon assimilation. The accumulation of BOA in soybean leaves reinforced these findings. and Obsahuje bibliografii
Leaf gas-exchange responses to shadefleck-sunfleck and sun-cloud transitions were determined for in situ Cycas micronesica K.D. Hill plants on the island of Guam to add cycads to the published gymnosperm data. Sequential sunfleck-shadefleck transitions indicated understory leaves primed rapidly but open field leaves primed slowly. Time needed to reach 90% induction of net CO2 assimilation (PN) was 2.9 min for understory leaves and 13.9 min for open field leaves. Leaf responses to sun-cloud transitions exhibited minimal adjustment of stomatal conductance, so PN rapidly returned to precloud values following cloud-sun transitions. Results indicate bi-directional leaf acclimation behavior enables mature C. micronesica trees to thrive in deep understory conditions in some habitats and as emergent canopy trees in other habitats. These data are the first nonconifer gymnosperm data; the speed of gas-exchange responses to rapid light transitions was similar to some of the most rapid angiosperm species described in the literature., T. E. Marler., and Obsahuje bibliografii
The Stefanyk Library of the Ukraine Academy of Sciences in Lvov houses the manuscript of a Czech medieval bible under shelf mark 9 O/Н Од. Зб. 3897. This bible was transcribed 1476-1478 by Jan Záblacký, a scribe of whom no details are known, and contains the complete collection of the books of the Old and the New Testaments without prefaces. We know neither the person who ordered the work nor the first owner, unless it was Jan Záblacký himself. Nor can we determine with any accuracy the place where the bible was written, although at the end of the manuscript Záblacký mentions that he completed it on 9th April 1478 in Kamenice, though there are several towns and villages of that name in Bohemia and Moravia. The times recorded by Jan Záblacký for individual books of the bible are of interest and value, as they enable us to reconstruct the rate at which the scribe transcribed the bible text and the average daily amount of text transcribed.
The Stefanyk Library of the Ukraine Academy of Sciences in Lvov houses the manuscript of a Czech medieval bible under shelf mark 9 O/Н Од. Зб. 3897. This bible was transcribed 1476-1478 by Jan Záblacký, a scribe of whom no details are known, and contains the complete collection of the books of the Old and the New Testaments without prefaces. We know neither the person who ordered the work nor the first owner, unless it was Jan Záblacký himself. Nor can we determine with any accuracy the place where the bible was written, although at the end of the manuscript Záblacký mentions that he completed it on 9th April 1478 in Kamenice, though there are several towns and villages of that name in Bohemia and Moravia. The times recorded by Jan Záblacký for individual books of the bible are of interest and value, as they enable us to reconstruct the rate at which the scribe transcribed the bible text and the average daily amount of text transcribed.