Gianfreda L., Sannino F., Violante A. (1995) Pesticide effects on the activity of free, immobilized and soil invertase. Soil Biology & Biochemistry, 27, 1201-1208.
ABSTRACT The influence of four pesticides (atrazine, carbaryl, glyphosate and paraquat) on the catalytic behaviour of invertase, either free, immobilized on inorganic and organic soil colloids or in soils, was investigated. Invertase was immobilized on a clean clay (montmorillonite), an organic compound (tannic acid), and on synthetic organo-mineral [Al(OH)x-tannate and Al(OH)x-tannate-montmorillonite] complexes. Soils with different physico-chemical properties were utilized. The effects of pesticides on invertase performance depended not only on the nature of the pesticide but also on the “status” of the enzyme, i.e. if free, immobilized or in soil. Glyphosate and paraquat enhanced the activity of invertase either free or immobilized on montmorillonite and both pesticides behaved as mixed-type non-essential activators. Activity decreases were instead measured for the enzyme immobilized on organic and organo-mineral matrices. Contrasting results (increases, decreases and no effects) were detected for soil invertase. A general inhibition effect was exhibited by methanol on free, immobilized or soil invertase, but the extent of inhibition depended on the enzyme microenvironment. The addition of atrazine and carbaryl caused partial increases of free and immobilized invertase activity, whereas carbaryl further reduced enzymatic activity in some soils.
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ABSTRACT: The heavy use of organophosphorus pesticides in northeastern China strongly affects the ecological functions and the quality of the soil environment. In this work, a 30-day soil incubation experiment was conducted to evaluate the potential of using soil available P and the activities of soil dehydrogenase and acid phosphatase as indicators of the application of methamidophos and glyphosate. Two kinds of unpolluted soils, phaiozem and burozem, were selected as the test soils. The higher application rate of organophosphorus pesticide to the two soils caused more release of PO4 which finally entered the soil available P pool, suggesting that soil available P is one of the effective chemical markers for biodegradation of organophosphorus pesticides. Methamidophos exhibited a significant inhibitory effect on the activity of soil dehydrogenase. The extent of enzyme inhibition was almost positively correlated with the insecticide concentration, and the enzyme activity was gradually restored after day 15. However, its effect on soil acid phosphatase activity (stimulation or inhibition) seemed to be indefinite, and varied with the application rate, soil type, and incubation time. In the case of glyphosate, soil acid phosphatase activity was depressed significantly and the depressing extent could be a function of herbicide concentration and incubation time, but soil dehydrogenase activity showed an irregular variation with the herbicide application rate and soil type. In general, dehydrogenase activity was a good biochemical indicator for the biodegradation of methamidophos, but for glyphosate biodegradation the indicator was acid phosphatase activity.Soil & Sediment Contamination - SOIL SEDIMENT CONTAM. 01/2011; 20(6):688-701.
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ABSTRACT: The effect of a new pesticide, acetamiprid, applied at normal field concentration (0.5 mg kg−1 dried soil) and at high concentration (5 and 50 mg kg−1 dried soil), on soil enzyme activities and soil respiration in upland soil was studied. The results showed that acetamiprid had a strong negative influence on soil respiration and phosphatase activity, and the enzyme activities in soil treated with 5 and 50 mg kg−1 dry soil were significantly (PEuropean Journal of Soil Biology - EUR J SOIL BIOL. 01/2006; 42(2):120-126.
- CHINESE JOURNAL OF ECO-AGRICULTURE 01/2009; 16(6):1504-1507.