Assessment of microbial activity and biomass in different soils exposed to nicosulfuron

Abstract

SummAryThe effects of the herbicide nicosulfuron on the abundance of cellulolytic and proteolytic microorganisms, activity of β-glucosidase and protease enzymes, and microbial phosphorus biomass were examined. A laboratory bioassay was set up on two types of agricultural soils differing in physicochemical properties. The following concentrations were tested: 0.3, 0.6, 3.0 and 30.0 mg a.i./kg of soil. Samples were collected 3, 7, 14, 30 and 45 days after treatment with nicosulfuron.The results showed that nicosulfuron significantly reduced the abundance of cellulolytic microorganisms in both soils, as well as microbial biomass phosphorus in sandy loam soil. The herbicide was found to stimulate β-glucosidase and protease activity in both types of soil and microbial biomass phosphorus in loamy soil. Proteolytic microorganisms remained unaffected by nicosulfuron.

Herbicidal effect on the bio-indicators of soil health- A review

“…Sofo et al (2012) reported that application of triasulfuron at ten-fold the field rate increased the β glucosidase activity in soil. Significant increase in β glucosidase activity in soil (5.6 to 29.4 per cent) was observed at 7 to 14 days after treatment with two highest concentrations (3.0 and 30.0 mg) of nicosulfuron, a sulfonyl urea herbicide (Santric et al, 2014). Application of carfentrazone ethyl at optimal dose increased the activity of β glucosidase in soil (Tomkiel et al, 2014).…”

“…Rasool et al (2014) reported that, the protease activity was stimulated initially by butachlor application but decreased towards the end of the experiment under unflooded condition, but under flooded condition, the effect was stimulatory. The herbicide nicosulfuron had a stimulating effect on the protease enzyme in loamy and sandy loam soil (Santric et al, 2014). Herbicide mixtures, bispyribac sodium + metamifop (60, 70, 80 and 90 g ha -1 ) and penoxsulam + cyhalofop butyl (120, 125, 130 and 135 g ha -1 ) recorded comparable or significantly higher values of protease enzyme activity at 30 DAS (15 days after herbicide application), 60 DAS (45 days after herbicide application) and at harvest Sheeja K Raj and Elizabeth K Syriac / J. Appl.…”