Inhibering van urease-aktiwiteite in sekere gronde van die sentrale besproeiingsgebiede in Suid-Afrika

Inhibition of urease activities in certain soils from the central irrigation areas in South Africa. The course of hydrolysis was monitored in four soils with different urease activities from the central irrigation areas after application of urea at the equivalent of 100 kg N ha-1. Simultaneously wit...

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Published in: South African journal of plant and soil Vol. 8; no. 4; pp. 212 - 214
Main Author: Thormahlen, F.P.J. and Du Preez, C.C
Format: Journal Article
Language: Afrikaans
English
Published: Taylor & Francis 12-01-1991
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Summary: Inhibition of urease activities in certain soils from the central irrigation areas in South Africa. The course of hydrolysis was monitored in four soils with different urease activities from the central irrigation areas after application of urea at the equivalent of 100 kg N ha-1. Simultaneously with the urea application, seven promising inhibitors were applied at a concentration of 50 mg kg-1. During incubation at 30�C the urea nitrogen was measured at regular time intervals until hydrolysis of the urea was completed. These data were used to calculate the urease activities of the different treatments for each soil. On average, hydroquinone reduced the urease activities of the four soils most (94%), followed by p-benzoquinone (93%), phenylphosphorodiamidate (85%), catechol (75%), phenyl mercuric acetate (70%), thiourea (30%) and ammonium thiosulphate (19%). Owing to the reduced urease activities, the time to complete the hydrolysis of urea was extended considerably.
ISSN: 0257-1862
2167-034X
DOI: 10.1080/02571862.1991.10634836