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Activity of nitrification inhibitors to several typical ammonia-oxidizing bacteria isolated
recently, i. e. Nitrosococcus, Nitrosolobus, Nitrosomonas, Nitrosospira and Nitrosovibrio spe-
cies was assayed using 2-amino-4-methyl-6-trichloromethyl-1,3,5-triazine (MAST), 2-amino-
4-tribromomethyl-6-trichloromethyl-1,3,5-triazine (Br-MAST), 2-chloro-6-trichloromethyl-
pyridine (nitrapyrin) and others, and compared to confirm the adequate control of ammonia-
oxidizing bacteria by the inhibitors. The order of activity of the
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A Silent Gene Allelic to Yeast Invertase Structural Gene
SUC2 Can Be Activated by Mutation to Direct the
Formation of a New Type of Invertase. (del Castillo
Agudo, L. Zimmermann, F. K.; Dept. de Microbiologia,
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Effect of Copper on Inhibition by Nitrapyrin of Growth
-pyrazole phosphate (DMPP). Nitrapyrin is less common than DCD or DMPP. A major drawback of NIs is that they are biodegradable and thus need to be reapplied in regular intervals. Additionally, their action is limited to the sites of nitrification, further adding to their cost ineffectiveness. However, N losses via nitrification are not only of agronomic value, but they also contribute to environmental pollution. The inhibition of N losses in form of N 2 O emissions as well as of NO 3 − leaching is influenced by several parameters, such as soil texture, temperature, and water