Assessing the impact of azadirachtin application to soil on ureaseactivity and its kinetic parameters

Authors : Ridvan KIZILKAYA, İraida SAMOFALOVA, Natalya MUDRYKH, Fariz MİKAİLSOY, İzzet AKÇA, Svetlana SUSHKOVA, Tatiana MINKINA

Pages : 976-983

View : 20 | Download : 6

Publication Date : 2015-12-01

Article Type : Research Paper

Abstract :Abstract: The kinetic parameters of soil urease have attracted considerable attention; however, little information is available on its kinetic parameters and behaviors in response to azadirachtin application to the soil. A short insert ignore into journalissuearticles values(14-day); field experiment was conducted using Albic Luvisol soil insert ignore into journalissuearticles values(loam texture; pH 6.70; electrical conductivity 0.81 dS m-1; CaCO3 content 0.04%; total organic carbon 0.99%); as the experimental soil in the Perm region of the Russian Federation to investigate the effects of different azadirachtin application doses on soil urease activity and its kinetic behaviors. The results showed that the highest urease activity was found under high azadirachtin application doses insert ignore into journalissuearticles values(0.6 L ha-1); compared to the control insert ignore into journalissuearticles values(0 L ha-1);, recommended insert ignore into journalissuearticles values(0.3 L ha-1);, and low insert ignore into journalissuearticles values(0.15 L ha-1); azadirachtin application doses at all different incubation times insert ignore into journalissuearticles values(1, 2, 3, 6, and 12 h);. Soil urease enzymes exhibited typical Michaelis-Menten kinetic behaviors; high azadirachtin application doses increased the substrate affinity constant insert ignore into journalissuearticles values(KM); and decreased the maximum reaction rates insert ignore into journalissuearticles values(Vmax); of soil urease. As compared to the control azadirachtin application dose, the low azadirachtin application dose increased the Vmax of soil urease; however, with low and recommended application doses, the Vmax of soil urease decreased. Overall, in this study, all azadirachtin application doses were effective in influencing the kinetic behavior of urease in Albic Luvisol.
Keywords : Azadirachtin, kinetic parameters, pesticide, urease, Vmax, KM, Vmax KM