Effect of temperature (20 and 40°C) and moisture content (30 and 80%) on the degradation of pyroquilon [1,2,5, 6-tetrahydropyrrolo (3, 2, 1-ij) quinolin-4-one] was investigated under laboratory incubated conditions in three soils. At the similar temperature and soil moisture, the influence of the soil type was small. Degradation fitted the first order kinetics, with half lives of 29.8 to 53.0 days depending upon the nature of soil, temperature and moisture. The rate of degradation increased with increase in soil temperature from 20 to 40°C and was highest at 40°C and 30 per cent soil moisture content in all the soils under study. The calculated activation energy (ΔEa) being between 1.41 to 2.50 kcal mol−1, and resistance of the pyroquilon to acid and alkali hydrolysis, indicated that the primary mechanism of pyroquilon degradation in these soils was probably enzymatic.
Soil, temperature, moisture, pyroquilon, degradation, kinetics, halflives, activation energy
