The soil proteolytic activity and organic production of corn under the conditions of applying different nutrition systems

Abstract

The effects of increasing amounts of mineral nitrogen (90, 120, 150 kg·ha-1) liquid (80 t·ha-1) and solid manure (45 t·ha-1) those of inoculation with Azotobacter chroococcum (the strain 84) on the soil proteolytic activity and corn yield grown in monoculture were surveyed over the 3-year-long research work. The research results indicated that proteolytic activity and corn yield depended highly on the fertiliser sorts, amounts and on the research year too. Over the first research year, the highest proteolytic activity was recorded on the variants with organic fertilisers, whereas the fertiliser stimulating effect markedly decreased, particularly with liquid manure over the following two years of the research. Mineral fertilisers were also found to remarkably stimulate the biological parameters we have been concerned above, particularly the mean N amount (120 kg · ha-1). While the highest corn yield could be obtained using 120 kg N · ha-1 throughout all the research years, its insignificant rise and barely altered soil proteolytic activity using corn seed inoculation with 84 Azotobacter chroococcum could be noticed.

Keywords

• Azotobacter
• corn
• yield
• liquid manure
• mineral fertilisers
• proteinase activity
• soil
• solid manure