ABSTRACT
The action of prometryn [1-6 ppm] was studied on nitrogen, carbon, nucleic acids, total amino acids contents as well as nitrate reductase enzyme acticvity of Nostoc muscorum Ag. Total nitrogen, total amino acids, total soluble sugars, DNA and RNA as well as nitrate reductase activity increased with increasing of prometryn concentrations until reached maxima at 3ppm, any increase above it was inhibitory. At 1 ppm, polysaccharides and total carbohydrates contents reached 5.94 and 8.28%, respectively: more than its respective control, while the concentrations above 1 ppm were inhibitory. The amino acids cysteine and alanine disappeared at all prometryn concentrations, while they were detected in control [untreated dry matter]
Subject(s)
Prometryne , MetabolismABSTRACT
The influence of various concentrations of pyrazon and prometryne on the intensity of growth and on the efficiency of dinitrogen fixation of Azotobacter vinelandii grown under static culture condition, was investigated. There was stimulating effects on the growth and cell mass yields in case of pyrazon, while there were deleterious effect on cell counts and biomass in case of prometryne. The sugar consumption in the presence of both herbicides were higher than that observed in the herbicide free medium. Moreover, the sugar consumption rate increased gradually with increased level of herbicide within the medium. The more available pyrazon for A. vinelandii grown under static culture condition, the higher the fixation rates and vice versa, while the nitrogen gains correlated inversely with the available prometryne in the medium. The increase in the concentration of pyrazon in the medium up to 100 ppm had a positive effect on the efficiency of dinitrogen fixation, while the power of N2-fixation correlated inversely with the available prometryne in the medium