Not only the presence of melilot but also the efficiency of melilot to fix nitrogen was significantly correlated with the ratio of resveratrol to resveratrol glucoside . This clearly depicts the differences between all of the substrates. Compost is revealed to be a substrate with a low efficiency of N fixation and, at the same time, with a higher proportion of resveratrol glucosides compared with its aglycones. The opposite is true for the clayish low nutrient substrates, clay and loess. Our data thus suggest the existence of glucose transport between the two plants, knotweed and melilot, and illustrate how costly nitrogen fixation is. As for the transport of nitrogen, the following observations have been made: 1 the rhizobia bacteroid membrane is permeable to amino acids ; 2 bacteroids cycle amino acids to the host plant http: www.biologie. uni hamburg.de b online e34 34b.htm; 3 roots exude both amino acids and sugars ; and 4 fungal hyphae are able to transport nitrogen , even amino acids , and can transport sugars both passively and actively .
The plants in our system are clearly interconnected by fungal hyphae, as the melilot acts as a donor plant of mycorrhizal fungi; vesicules and hyphae, but no arbuscules, have been found in the roots of knotweed growing together with melilot, but none have been observed in the absence GW9662 of melilot. Transport of substances via hyphae is to be expected in our system. However, we did not examine the mechanisms of transport, which require further study. Conclusions A three year field experiment revealed that 2.6 t of dry mass and 8.5 kg of stilbenes are produced per hectare of knotweed. Spoil bank soils are thus promising areas to grow knotweed, namely this hexaploid clone of R. bohemica, as a medicinal plant for production of resveratrol and resveratrol containing substances. In a pot experiment, the highest knotweed biomass production was observed in plants grown on high nutrient substrates, namely compost.
However, the concentrations of organic constituents studied were higher in plants grown in the presence of melilot on clayish low nutrient substrates. Melilot significantly increased the contents of resveratrol derivatives in knotweed roots and rhizomes in plants grown on clay, clayCS and loess. On most substrates, the contents of nitrogen and emodin in the Tubastatin A selleck chemicals roots and rhizomes of knotweed were also increased by the presence of melilot. Melilot showed a more pronounced effect than the substrate on production of resveratrol derivatives and emodin. Relationships were found between nitrogen, phosphorus, emodin, and belowground knotweed biomass. The presence of melilot revealed additional relationships between these characteristics, and resveratrol and resveratrol derivatives. Strange But Manageable Rucaparib Tactics