The article is devoted to František Čáda. The author describes Čáda´s life dedicated to archivistic, teaching, research and editorial work. She describes ow the changes of the political regime in 1948 affected the life of this outstanding Czech legal historian, a diligent editor and and excellent teacher who was forced to leave the university. Only thanks to their commitment and assistance prof. Vojtíšek later found application in manuscirpts research. Diligent and accurate work brought him recognition not only among law historians even among codicologists. and Medailonek
Leaf-root interaction is a critical factor for plant growth during maturation and activity of roots is maintained by a sufficient supply of photosynthates. To explain photosynthate distribution among organs in field crops, the node unit hypothesis is proposed. One node unit consists of a leaf and an upper adventitous root, as well as the axillary organs and the lower adventitious root, which is adjacent to one node. Using 14C as tracer, the carbon distribution system has been clarified using spring wheat, soybean, tomato, and potato. The interrelationship among organs from the strongest to the weakest is in the following order: (1) within the node unit > (2) between the node unit in the same or adjacent phyllotaxy > (3) in the main root or apical organs, which are adjacent to the node unit. Within the node unit, 14C assimilated in the leaf on the main stem tended to distribute to axillary organs in the same node unit. The 14C assimilated in the leaf of axillary organs tended to distribute within the axillary organs, including adventitious roots in the axillary organ and then translocated to the leaf on the main leaf of the same node unit. In different organs of the node unit in the same or adjacent phyllotaxy, 14C assimilated in the leaf on the main stem was also distributed to the organs (node unit) belonging to the same phyllotaxy in dicotyledons, while in monocotyledons, the effect of phyllotaxy on 14C distribution was not clear. Among roots/apical organs and node unit, 14C assimilated in the upper node unit was distributed to apical organs and 14C assimilated in the lower node unit was distributed to roots. Thus the node unit hypothesis of photosynthate distribution among organs is very important for understanding the high productivity of field crops. and M. Osaki ... [et al.].
IsiA is a membrane-bound Chl a-antenna protein synthesized in cyanobacteria under iron deficiency. Since iron deficiency is a common nutrient stress in significant fractions of cyanobacterial habitats, IsiA is likely to be essential for some cyanobacteria. However, the role it plays in cyanobacteria is not fully understood. In this review paper, we summarize the research efforts directed towards characterizing IsiA over the past three decades and attempt to bring all the pieces of the puzzle together to get a more comprehensive understanding of the function of this protein. Moreover, we analyzed the genomes of over 390 cyanobacterial strains available in the JGI/IMG database to assess the distribution of IsiA across the cyanobacterial kingdom. Our study revealed that only 125 such strains have an IsiA homolog, suggesting that the presence of this protein is a niche specific requirement, and cyanobacterial strains that lack IsiA might have developed other mechanisms to survive iron deficiency., H.-Y. S. Chen, A. Bandyopadhyay, H. B. Pakrasi., and Obsahuje bibliografické odkazy
Properties and functional activity of the photosynthetic apparatus in Vida faba L. plants grown at 10, 50, 100 and 150 W PAR were studied. Responses of the photosynthetic apparatus in high, HI (125 W m-^) and low irradiance, LI (10 W m-2) plants to a change in irradiance (/) depended on the leaf age. The chlorophyll (a + b) content per unit of the leaf area remained relatively constant during the first 3 d after a shift in /. Acclimation of the photosynthetic electron transport activity to I depended on / in the preceding period and on the phase of leaf development.